Volume 9, Number 2 (January 2022):3415-3429, doi:10.15243/jdmlm.2022.092.3415 ISSN: 2339-076X (p); 2502-2458 (e), www.jdmlm.ub.ac.id
Open Access 3415 Review
An overview of technologies suitable for handling Indonesian agricultural soils contaminated with persistent organic pollutants
Dwindrata Basuki Aviantara1*, Mohammad Yani1, Nastiti Siswi Indrasti1, Gunawan Hadiko2
1 Agroindustrial Engineering IPB University, Dramaga – West Java 16680, Indonesia
2 Centre for Ceramics, Bandung – West Jawa 40272, Indonesia
*corresponding author: [email protected]
Abstract Article history:
Received 15 September 2021 Accepted 29 December 2021 Published 1 January 2022
Since Indonesia have signed and ratified Stockholm Convention on Persistent Organic Pollutants (POPs) in 2009, the country must make efforts to manage POPs appropriately. A number of pollution evident of POPs has occurred in Indonesia, either air, soil or water. Agricultural soils are not excluded from POPs pollution as the result of halogenated pesticide uses or other unidentified sources. Contamination of POPs to humans have been detected, as well as indicated potential exposure of POPs to humans. Based- catalyzed decomposition is a method that can be used to decompose or decontaminate POPs. Limestone can be processed to produce calcium-based catalyst that can apply for POPs decomposition. Indonesia is a country rich in limestone natural resources to produce calcium. However, calcium is inferior to sodium or potassium in reactivity for the dehalogenation of POPs.
Thus, more evaluation is needed in order for synthesizing proper and economical calcium-based catalyst to alleviate POPs pollution in Indonesia.
Keywords:
base calcium catalyst dehalogenation POPs
To cite this article: Aviantara, D.B., Yani, M., Indrasti, N.S. and Hadiko, G. 2022. An overview of technologies suitable for handling Indonesian agricultural soils contaminated with persistent organic pollutants. Journal of Degraded and Mining Lands Management 9(2):3415-3429, doi:10.15243/jdmlm.2022.092.3415.
Introduction
When Stockholm Convention entered into force in 2004, as shown in Table 1, initially 12 types (recognized as Dirty Dozen, most of them are pesticides) of POPs were regulated (Kovner, 2017). At present, at least 29 types of POPs have been listed in Stockholm Convention. They may add more during the COP9 (Conference of the Parties) meeting of the Stockholm Convention held in Geneva – Switzerland (Secretariat of the Stockholm Convention, 2019).
Countries that have signed and ratified the Stockholm Convention must establish National Implementation Plan (NIP) to manage POPs and establish the necessary regulations accordingly to support the NIP implementation.
With a strict regulation, then substantial penalties can result from misuse or improper storage of hazardous substances and POPs matters that result
in chemical leaks, chemical leaching and chemical spills. The use of these chemicals requires proper storage facilities and labeling systems, emergency cleanup equipment, emergency cleanup procedures, safety equipment, as well as safety procedures for proper handling, application and disposal that are often subject to mandatory standards and regulations (Speight, 2017). Nowadays, as a result of growing awareness of the health hazards of pesticides and related chemicals, including POPs, these materials are carefully regulated to control their use, stockpile and transport to protect society and the environment from exposure of hazardous substances. On the other hand, even though fertilizers have been in an opposite category, considered useful, safe and inert;
nonetheless, the use of agrochemicals to some extent created other environmental problems as such prompt the search for nonchemical methods to enhance soil
Open Access 3416 fertility and deal with crop pests. These alternatives,
however, are still emerging and are not yet in widespread use (Speight, 2017).
Indonesia has signed and ratified the Stockholm Convention through Law Number 19 of 2009 (Ministry of Environment Republic of Indonesia, 2014), and the urgency to ratify the international convention was also elaborated (Santoso, 2009). Even though Stockholm Convention has been ratified by the
Government of Indonesia, however, technologies applied for POPs management in Indonesia still lacking. This paper discusses POPs chemicals used in agriculture and agroindustry and the impact they may have on the changes of environmental compartments quality. Moreover, an attempt on the search for appropriate available technologies in dealing with POPs in agricultural as well as agroindustrial sectors is also taken into account.
Table 1. Dirty dozen chemical list of Stockholm Convention as appeared in 2004.
POP Chemical Structure Global Historical Use/Source
Aldrin
1,2,3,4,10,10-hexachloro- 1,4,4a,5,8,8a-hexahydro- 1,4:5,8-dimethanonaphthalene Dieldrin
(1aR,2R,2aS,3S,6R,6aR,7S,7aS) -3,4,5,6,9,9-hexachloro- 1a,2,2a,3,6,6a,7,7a-octahydro- 2,7:3,6-dimethanonaphtho[2,3- b]oxirene
Aldrin
Dieldrin Insecticides used on crops such as corn and cotton; also used for termite control.
Chlordane Octachloro-4,7- methanohydroindane
Insecticide used on crops, including vegetables, small grains, potatoes, sugarcane, sugar beets, fruits, nuts, citrus and cotton.
Used on home lawn and garden pests.
Also used extensively to control termites.
DDT
1,1,1-trichloro-2,2-di(4- chlorophenyl)ethane
Insecticide used on agricultural crops, primarily cotton and insects that carry diseases such as malaria and typhus.
Endrin
(1aR,2S,2aS,3S,6R,6aR,7R,7aS) -3,4,5,6,9,9-hexachloro- 1a,2,2a,3,6,6a,7,7a-octahydro- 2,7:3,6-dimethanonaphtho[2,3- b]oxirene
Insecticide used on crops such as cotton and grains; also used to control rodents.
Mirex
1,1a,2,2,3,3a,4,5,5,5a,5b,6- dodecachlorooctahydro-1H- 1,3,4-
(methanetriyl)cyclobuta[cd]pent alene
Insecticide used to combat fire ants,
termites and mealybugs.
They are also used as a fire retardant in plastics, rubber and electrical products.
Heptachlor
1,4,5,6,7,8,8-Heptachloro- 3a,4,7,7a-tetrahydro-4,7- methano-1H-indene
Insecticide that is used primarily against soil insects and termites. Also used against some crop pests and to combat malaria.
Open Access 3417
POP Chemical Structure Global Historical Use/Source
Hexachlorobenzene
Fungicide used for seed treatment.
Also, an industrial chemical is used to make fireworks, ammunition, synthetic rubber and other substances.
Also unintentionally produced during combustion and the manufacture of
certain chemicals.
And, an impurity in certain pesticides.
PCBs (polychlorinated biphenyls)
Used for a variety of industrial processes and purposes, including in electrical transformers and capacitors, as heat exchange fluids, as paint additives, in carbonless copy paper and in plastics.
Also unintentionally produced during combustion.
Toxaphene Insecticide that is used to control pests
on crops and livestock, and to kill unwanted fish in lakes.
Dioxins and furans
Dioxin
Furan
Unintentionally produced during most forms of combustion, including burning of municipal and medical wastes, backyard burning of trash and industrial processes.
Also, it can be found as trace contaminants in certain herbicides, wood preservatives, and PCB mixtures.
Persistent Organic Pollutants in Agriculture and Agroindustry
Pesticides sprayed on agricultural lands or fields due to wind force, or air convection might drift away from the targeted area and pose endanger to humans, plants and animals (Jimenez et al., 2015). Pesticides, for example, DDT (1,1,1-trichloro-2,2-bis(4- chlorophenyl)ethane), are still detected in the environment because of very slow degradation and persistent for a long time as such contaminate wildlife, well water, food and even humans with whom they come in contact (Speight, 2017). Spatial migration of DDT and other organochlorine pesticides (OCPs) from agricultural lands to surface waters has also been reported (Manuaba, 2007).
Agricultural pollution resulted from POPs containing pesticide uses also occurred in several locations of Indonesia. A report published by the Ministry of Agriculture elaborated on ten types of pesticide regulated by the Stockholm Convention (Suharsih et al., 2015). As demonstrated in Table 2,
among the ten types of pesticide assessed from more than 700 agricultural soils collected from three regencies of Central Java Province (Wonosobo, Banjarnegara and Cilacap Regencies) only Mirex was the only one that did not exceed the maximum permissible value.
A study conducted by the Ministry of Environment (Pusarpedal, 2014) in three provinces of Indonesia also demonstrated POPs have contaminated Indonesian agricultural soils, as shown in Figures 1-3.
From the figures, it can be confirmed that although the use of DDT in agricultural soils has been banned in Indonesia since 2001 (Ministry of Environment, 2014), soils contaminated with DDT are still detected.
This is because to reduce DDT to achieve half of its original proportion, then tens to hundreds of years is required depending on climatic and soil conditions (Brodskiy et al., 2016). As can be seen in Figure 2, a transformation products of DDT, i.e. DDE (1,1- dichloro-2,2-bis(4-chlorophenyl)ethane) and DDD (1,1-dichloro-2,2-bis(4-chlorophenyl)ethane), were detected.
Open Access 3418 Table 2. Levels of pesticide detected in Indonesian agricultural soils*.
Pesticide Regency MRL**
Wonosobo Banjarnegara Cilacap
Lindane 0.0141 ± 0.0255 0.0106 ± 0.0032 0.0170 ± 0.0083 0.010
Heptachlor 0.0120 ± 0.0285 0.0167 ± 0.0582 0.0012 ± 0.0013 0.039
Aldrin 0.0069 ± 0.0070 0.0100 ± 0.0113 0.0073 ± 0.0067 0.029
Chlordane 0.0581 ± 0.0245 0.0912 ± 0.0600 0.0387 ± 0.0547 0.050
Endosulfan 0.0034 ± 0.0027 0.0576 ± 0.6100 0.0082 ± 0.0074 0.009
Toxaphene 0.8908 ± 1.9047 0.3765 ± 0.2764 0.1938 ± 0.2741 0.500
Dieldrin 0.0551 ± 0.0870 0.0653 ± 0.1769 0.0046 ± 0.0019 0.011
Endrin 0.0096 ± 0.0164 0.0386 ± 0.0458 0.0218 ± 0.0177 0.008
DDT 0.0231 ± 0.0870 0.0059 ± 0.0056 0.0155 ± 0.0187 0.015
Mirex 0.0057 ± 0.0061 0.0047 ± 0.0045 0.0055 ± 0.0041 0.027
Source: Suharsih et al. (2015), *Unit in part per million (ppm), ** Maximum residue levels.
Figure 1. DDT and its transformation products (unit in ng/g) on agricultural soils collected in Batu Regency, East Java Province (Modified from Pusarpedal, 2014).
Figure 2. DDT and its transformation products (unit in ng/g) on agricultural soils collected in Bandung Regency, West Java Province (Modified from Pusarpedal, 2014).
0 10 20 30 40 50 60 70 80 90
p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD Soil of Tulung Rejo
Village - Bumiaji Soil of Junggo
Village - Bumiaji Soil of Tulung Rejo Village - Junrejo
2011 2012 2013
0 5 10 15 20 25
p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD Lindan p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD Cabbage garden soil
Leuwibingbin Paddy soil of mid city
Soreang District Paddy soil
near Ciwidey River
2012 2013
Open Access 3419 Figure 3. DDT and its transformation products (unit in ng/g) on agricultural soils
collected in Medan, North Sumatra Province (Modified from Pusarpedal, 2014).
The two breakdown products are similar in inducing toxicity as the parent molecule DDT (Agapkina, 2017). Even DDE that is slightly more toxic than DDT has been found to dominate soils collected from Batu Regency, East Java Province. Air monitoring programs on eight organochlorine pesticides, a collaboration between Global Atmospheric Monitoring Station of Bukit Kototabang, West Sumatra Province, Indonesia and Environment Canada (Nahas, 2009), revealed that, as shown in Figure 4, air pollution caused by POPs dominated agricultural and urban areas as compared to the background, rural and
polar areas. As can be seen in the figure, α- and γ- hexachlorocyclohexane, cis-chlordane and heptachlor dominated agricultural areas. Meanwhile, heptachlor epoxide, trans-chlordane and trans-nonachlor dominated urban areas. However, the cause of the high abundance of dieldrin found in the background area was uncertain. Another example of pollution caused by POPs substances in agroindustry is the use of PCP (pentachlorophenol) as a biocide in wood preservation technique to protect the wood from deterioration due to fungal rot or decay, sapstain, molds, or wood-destroying insects (USEPA, 2017).
HCH = hexachlorocyclohexane, hept = heptachlor, hepx = heptachlor epoxide TC = trans chlordane, CC = cis chlordane, TN = trans nonachlor
Figure 4. Normalized relative abundance of POPs at five sampling locations (Source: Nahas, 2009).
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD p,p'-DDT p,p'-DDE p,p'-DDD o,p'-DDT o,p'-DDE o,p'-DDD Garden soil
Kabanjahe, Karo Paddy soil
Batu Karang Village Orange garden soil
Sarinembah Orange garden soil Jandi Meriah
2011 2012 2013
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
A B C D E A B C D E A B C D E A B C D E A B C D E A B C D E A B C D E A B C D E
α-HCH γ-HCH Hept Hepx TC CC TN Dieldrin
Open Access 3420 In addition to POPs contamination of agricultural
lands and surface waters, evidence that horticultural products have been contaminated with organochlorine pesticides were reported as well. A study in Karo Regency, North Sumatra Province, Indonesia, elucidated carrot (Daucus carota) has been contaminated with γ-BHC (lindane), endosulfan and aldrin of which levels were exceeding the threshold of maximum residue level, i.e. 0.10 ppm (Sinulingga 2006). Furthermore, a similar study of five groups of foodstuff that included vegetables (carrot, potato, cucumber, corn and onion), rice, pulses (green bean and soybean), nuts (peanut) and fish (milkfish) was collected from traditional markets (Bogor, Jakarta and Yogyakarta) in Indonesia demonstrated that OCPs were only detected in fatty foodstuffs, such as soybean, peanut and milkfish (Shoiful et al., 2013). Another study regarding POPs contamination of foods has been reported as well (Winarti and Munarso, 2005).
Toxicity of Persistent Organic Pollutants Typically, agrochemicals are toxic, and when stored in bulk storage systems, they may pose serious environmental problems, particularly in the event of accidental spills caused by improper storage, leaking or leaching. Because of that, in many countries, the use of agrochemicals are rigorously regulated and require governmental permits to purchase or use them.
Although the use of agrochemicals is directed at increasing plant and animal crop production, however, they may also induce deleterious effects to the environment. Excessive use of both fertilizers and pesticides on agricultural lands or soils has led to the contamination of surface water and groundwater with chemical compounds that, at certain concentrations, may become poisonous to both humans and animals.
Furthermore, the runoff (or leaching from the soil) of fertilizers into streams, lakes and other surface waters can initiate algal blooming, which can have an adverse effect on the life-cycle of fish and other aquatic animals.
Chemicals, including pesticides, are widely distributed in the environment, creating many possible sources of exposure to these chemicals for humans.
Hazardous substances that are present in ambient or indoor air may be inhaled, while those in water or food may be ingested. The most prevalent way environmental chemicals penetrate human skin is through direct contact. However, exposure through the skin may also occur as a result of contact with chemical contaminants in air and water (McDowall, 2002).
Technologies for the Destruction of Persistent Organic Pollutants
The process for POPs destruction could be categorized into chemical and biological techniques or a combination of the two. Chemical techniques can be
classified into thermal and non-thermal processes. On the other hand, biological technique comprises microbial and plant-based processes. Generally, chemical processes are running at appreciable rates but are costly. On the other hand, although the biological process is considered safer and cheaper than the chemical process, it requires appreciable time to achieve a similar performance as chemical processes.
Biological processes
Although POPs are recalcitrant compounds, there are several environmental processes, mostly microbial degradation, that can transform POPs into other forms that are not necessarily simpler and less toxic (Zacharia, 2019). For example, DDT is known to undergo a microbial transformation and is thus amenable to bioremediation. However, the process can be extremely slow and can result in the production of DDE, a known toxic and recalcitrant compound, in aerobic conditions. To execute bioremediation, microorganisms mediated process (mostly by bacteria but sometimes also fungi and algae), two common methods depending on the type of pollutants and site conditions are usually employed, i.e. in-situ or ex-situ.
Probably, the use of in-situ bioremediation is more cost-effective as the method is not necessary to separate the contaminated matrices from their original environment and transport them to another place for treatment. The frequently used bioremediation methods for the in-situ approach are natural attenuation, biostimulation and bioaugmentation. On the contrary ex-situ approach requires the separation of the polluted matrices from their original environment and transport them to another place for treatment. The commonly used methods for the ex-situ approach in soil bioremediation are landfarming and biopile (Lukic 2017; Megharaj and Naidu, 2017).
Another approach to deal with environmental pollution caused by POPs is the use of plants as agents to remediate POPs contaminated matrices known as phytoremediation. The removal of persistent organic pollutants (POPs) in soils through phytoremediation at initial concentrations ranging from 20 to 321 mg/kg has been investigated under different planting patterns (Luo and Lei, 2014; Lei, 2015). Results of the study demonstrated that 75% of pyrene and 68% of benzo(a)pyrene that present in contaminated soil can be reduced within 70 days of experiment if both Brassica campestris (mustard) and Medicago sativa (alfalfa) were planted at the same time. Such results were better than planting mustard or alfalfa individually (Luo and Lei, 2014; Lei, 2015). Clearly, the study demonstrated that the biological process for POPs degradation might require substantial duration to complete.
Furthermore, the use of natural coagulants such as Guar gum and Xanthan gum for treating POPs of landfill leachate and agricultural wastewater was also trialled (Pariatamby and Kee, 2016). The use of natural
Open Access 3421 coagulants is more preferred as compared to chemical
coagulants due to minimal requirement of dosage, efficiency at low temperature and produce small volume of sludge. In addition, chemical coagulants are generally more expensive, inducing toxicity to living organisms and most of them are low biodegradability (Verma et al., 2012).
Although there are many evidence that POPs could be degraded biologically, nevertheless, to the present, none of the biological techniques demonstrated proven technology in the context of time frame because of slow process irrespective of their low cost of operation as compared to the physical and chemical methods. Therefore, in general, POPs are not amenable by direct biological treatment (Levec and Pintar, 2007; Adeyemo et al., 2012; Wang et al., 2014).
To overcome this, biomolecular engineering has been trialled (Ang et al., 2005) but still remained far from proven for rapid remediation processes.
Thermal processes
At present, there are many types of POPs destruction technologies based on thermal processes. Perhaps, the most used methods are incineration using fossil fuels at temperatures in the range 870-1200 oC. Several types of burner fed with fossil fuels are available such as static kiln incinerator, rotary kiln incinerator, liquid injection incinerator, fluidized bed incinerator and cement kiln. Burner having the capability to provide a temperature of at least 1200 oC is classified as high- temperature incinerator.
Incineration at high temperatures is carried out at two steps, with different burning chambers is used at each step. The first burning chamber frequently is referred to as the primary chamber or the main chamber is used to burn POPs substances. The second chamber referred to as the secondary chamber or after burner, is used to burn the generated smoke from the first chamber. By using the after burner maximum destruction of POPs, i.e. at least 99.99% of Destruction
and Removal Efficiency (DRE) with Removal Efficiency (RE) of at least 99.99995% (McDowall, 2002) will be obtained. The effectiveness of the incinerator is strongly dependent upon processed matrices, turbulence, temperature and retention time along with the burning chamber. In general, incineration is a complex process in which kinetic consideration and the non steady-state process is interwoven. Figure 5 depicts a scheme of incineration technology for hazardous substances using a static burning chamber type.
Although incineration technology is a proven technology, however, failure in keeping good management during operation is potentially creating byproducts that may induce deleterious effects to the environment and living organisms. Occasionally such byproducts might have more hazardous characteristics compared to the parent molecules. During the incomplete burning process of chlorinated organic compounds like PCBs (polychlorinated biphenyls) harmful byproducts such as dioxins and furans can be generated. The two latter compounds are very toxic and persist in the environment for a long time. Dioxins and furans are potentially created during the slow cooling of hot gases emitted from the secondary burning chamber. The probability of dioxin and furan generation is a function of temperature, presence of chlorinated compounds and catalyst. Table 3 provides advantages, challenges as well as key points of the application of incineration technology for POPs.
In addition to fossil fuel burner, another burner based on high electrical voltage called plasma arc incineration, around 20,000 volts has also existed. This kind of burner is able to provide very high temperature, 10,000 oC compared to fossil fuels burners. With such a high temperature, all POPs will rapidly (20–50 milliseconds) and completely destroyed. However, the installation cost of the electrical discharge method to destroy POPs is very expensive, as shown in Table 4.
Figure 5. Diagram of static kiln incinerator.
(Source: Herlambang et al., 2015)
Open Access 3422 Table 3. Performance description of incineration technology for POPs destruction.
Advantage Challenge Key point
Proven technology
In a highly controlled process the total destruction of POPs may approximate 100%
Results of complete destruction process of POPs are CO2, H2O and chloride
Waste materials may use as alternative fuels
Process must be controlled carefully
Needs removal system for dioxins and furans
Capable of treating huge amount of wastes or contaminated materials
Total destruction
High DRE
Cost (USD 200–5000 for every ton treated materials)
Source: McDowall (2002).
Table 4. Performance description of plasma arc technology for POPs destruction.
Advantage Challenge Key point
Proven technology
In a highly controlled process the total destruction of POPs may approximate 100%
Results of complete destruction process of POPs are CO2, H2O and chloride
Installation is very expensive,
USD 1.6 M Capable of treating huge
amount of wastes or contaminated materials
Total destruction
High DRE
Medium cost (USD 400–2000 for every ton treated materials) Source: Environment Australia (1997).
Another thermal process for POPs destruction is by using a process implemented in cement production or cement clinker (Li et al., 2012). The process is referred to as co-processing (UNEP, 2012). The term has restricted definition in that using of substances present in waste materials as part of the production process for the purpose of energy or material recovery. By this way, the use of conventional energy or raw material can be avoided or reduced. A waste co-processing that is controlled carefully will provide benefit from the energy and material utilization that present in wastes.
For developing countries where the infrastructure of waste management has not been optimally established, then carefully controlled co-processing may provide practical solutions, effective cost and environmentally sound compared to management of waste by landfill or incineration. The waste co-processing system is an intensive-resource process (UNEP, 2012) of which for one-ton cement clinker product required 1.5–1.7 tones of raw materials and as the process occurs at high temperature (2000 oC) will need energy supply equivalent to 60-130 kg of fossil fuel and electricity 105 kWh. This is an important element in the management system of raw materials and energy for cement clinker production. From the total cost of cement clinker production, the expense component for fuel and electricity may comprise 40%.
Because of long retention time and turbulence movement within kiln then complete destruction of POPs could be achieved in 5–6 seconds. In addition, cement production processes utilize calcareous materials comprising mass > 60% as such having good scrubbing capability. Thus, the process of cement
clinker production is a self-cleaning kiln. Another advantage of co-processing to destroy POPs in cement clinker production is the avoidance of solid waste generation because all materials are becoming cement products. The ideal position to feed POPs into the rotary kiln is at the mid of the column where the temperature is at least 1100 oC. However, as mostly the rotary kiln for cement clinker production is not designed to fed material in the middle position, then modification of the kiln is required. This may create another problem. Table 5 presents the advantages, challenges and key points of co-processing of POPs in cement clinker production. Figure 6 depicts concise information on the cement clinker production process.
Nonthermal processes
The generally accepted meaning for the nonthermal process for POPs destruction is any process that may require heating, but the typical temperature is not more than 400–450 OC. The nonthermal processes for POPs destruction include oxidation and reduction (redox) mechanisms, nucleophilic substitution and photolysis.
However, POPs destruction through the use of microwave-assisted, gamma and beta (electron) irradiations were also recorded (Shammi et al., 2007, Trifan and Calinescu, 2009; Sumartono, 2012, Melnikova et al., 2019).
Catalysed decomposition of POPs
Unlike POPs destruction by using thermal process or critical and subcritical methods, the noncatalyzed POPs destruction proceed at rates of hours to days in
Open Access 3423 order to achieve an acceptable level of concentrations
considered safe to living organisms and the environment. To accelerate the rate of POPs transformation or degradation, then catalyst must be involved. In general, three types of catalytic processes, i.e. photocatalysis, homocatalysis and heterocatalysis, may be used in the destruction of POPs.
Photoinduced catalysis of POPs
Photocatalysis is one of the most important chemical methods to mitigate the energy and environmental crisis via converting inexhaustible solar energy into clean chemical potential (Zeng et al., 2016).
Decomposition of POPs in an aqueous medium using a photocatalytic technique has been considered an advantageous technology. Usually, the technique is carried out by using semiconductor photocatalysts such as TiO2, ZnO, Fe2O3, CuS, CdS (Doll and
Frimmel, 2005; Azrague and Ostherhus, 2009;
Mahmiani et al., 2016; Pi et al., 2017) or a combination of metal oxides such as TiO2/SiO2, TiO2/ZrO2, TiO2/WO3, TiO2/Fe2O3, TiO2/SnO2, TiO2/Ln2O3 and TiO2/RuO2 (Sun et al., 2009; Han et al., 2010; Sorescu and Xu, 2011; Ulgen and Hoelderich, 2011; Mahlambi et al., 2015). The UV/TiO2 photocatalytic process is among the most studied AOPs (advanced oxidation processes) and has been shown to have the potential for effectively treating many POPs (Azrague and Ostherhus, 2009). The titania (TiO2) nanocatalysts have the potential to destroy recalcitrant contaminants or hazardous chemical wastes to produce innocuous end products such as CO2 and H2O. Thus the Titania nanoparticles are expected to play an important role in the remediation of environmental and pollution challenges (Mahlambi et al., 2015).
Table 5. Performance description of co-processing technology for POPs destruction.
Advantage Challenge Key point
Proven technology
In a highly controlled process the total destruction of POPs may approximate 100%
Results of complete destruction process of POPs are CO2, H2O and chloride
Waste materials may use as alternative fuels or raw materials
Result of destruction in the form of chlorides becomes part of cement clinker product
Modification of rotary kiln is required to fed POPs containing materials
Needs removal system for dioxins and furans
Process must be carefully controlled
Capable of treating huge amount of wastes or contaminated materials
Total destruction
High DRE
Medium cost (USD 200–5000 for every ton treated
materials)
Source: McDowall (2002).
Figure 6. Process of cement clinker production.
(Modified from The GTZ-Holcim Public Private Partnership, 2013)
Open Access 3424 Despite that the photocatalysis process can be applied
for decomposing POPs, several drawbacks of this technique still remain. Major drawbacks of photocatalysis are easy photo corrosion, easy agglomeration, low solar energy conversion efficiency and difficult post-separation of the inorganic catalysts (Wang et al., 2014; Dong et al., 2015; Pi et al., 2017).
In the case of TiO2 the major recognized drawbacks were the photogenerated electron-hole pair has a high recombination rate, in aqueous solutions the quantum yield is low and the band gap value is high, i.e. 3.2 eV, as such the photocatalytic proceed under ultraviolet irradiation (Kang et al., 2012; de Mendoca et al., 2014;
Mahmiani, 2016). Also, using sunlight as an energy source in the applications employing titanium dioxide is rather limited, as only 3–4% of sunlight falls in the ultraviolet range (Baran et al., 2008). Such drawbacks may hinder the large-scale applications of photocatalysis for POPs destruction.
Recently with the development of Metal Organic Frameworks (MOFs), a structure of highly porous material with an ultra-high surface area consisting of metal ions and organic ligands, as shown in Figure 7, then photocatalysed decomposition of POPs became promising technology. The distinctive nature of MOFs has rendered them as promising candidates for photocatalysis not only because they combine the benefits of heterogeneous catalysis and homogeneous catalysis but also because they facilitate the possibility of merging multifunctional catalytic sites for concerted or cascade photocatalysis (Zeng et al., 2016).
Currently MOFs has been recognized as the most porous materials that exhibited very large surface area, above 5000 m2/g, and very high internal pore volume, above 1 cm3/g (Garcia and Ferrer, 2013).
In addition to photodecomposition as described above, another method combining mechanical and chemical effects of ultrasound, operates in the range of
frequency 16 kHz to 500 MHz, with photostimulation is also emerging (Cravotto and Cintas, 2012; Li, 2012).
High power ultrasound has been known to destroy a wide range of POPs such as DDT, lindane, endosulfan, 2,4,5-T, tetrachloronaphthalen, atrazine, imazine, total petroleum hydrocarbons (TPH), as well as tetrabutyltin (TBT) (Collings et al, 2006). The effect of ultrasound on adsorbed pollutants to soils or sediments is weakening of binding between adsorbate and adsorbent as such that promotes the desorption process. Furthermore, in addition to triggering the desorption of contaminants, ultrasound is also capable of promoting the formation of free radicals, e.g. •OH radical, that can destroy the contaminants (Flores et al., 2007). Besides the environmental application, other implementations of ultrasound are also recognized, as shown in Figure 8 (Shresta et al., 2012).
Figure 7. Schematic illustration of a metal-organic framework (MOF).
(Source: Berger M, No Year)
Figure 8. Diverse applications of ultrasound.
Base-catalysed decomposition of POPs
Principally, base-catalyzed decomposition is a process similar to predecessor glycolate dehalogenation. The proton donor that acts as a nucleophilic substitution
agent is derived from organic compounds having low oxidation potential in a basic medium (Rahuman et al., 2000). Initially, this technique was developed by Risk Reduction Engineering Laboratory EPA
Open Access 3425 (Environmental Protection Agency) in collaboration
with Naval Facilities Engineering Services Centre (NFESC) to remediate liquids, soils, sludges and sediments contaminated with chlorinated organic compounds such as pesticides, polychlorinated biphenyls (PCBs), dioxins and furans (Zinoviev et al., 2007)
In the beginning, the base-catalyzed decomposition technique was developed for treating soils contaminated with PCBs. In dealing with the contaminated soils, a pretreatment was required to leach PCBs from soils through the thermal desorption method. To enhance the organic pollutants leaching from soils, a sodium carbonate compound was added.
The sodium carbonate salt has the ability to reduce soil aggregate stability as such lowering its adsorptive capacity. The temperature used in thermal desorption is dependent on the volatilization temperature of the material being desorbed, usually around its boiling point. For PCBs such a temperature is in the range 200- 400 oC.
The application of base-catalyzed decomposition range from treatment of PCBs liquids to organochlorine pesticides. The treatment can be direct or by two separate steps depending on the type of the feed (Zinoviev et al., 2007). The first step is the indirect thermal desorption (in case of contaminated soil or solid matrices), which is a continuous flow process and the second step is the intrinsic BCD reaction of POPs (condensates from the first step or liquid POPs that can be fed directly), which is a batch process. The implementation of BCD process in Guam has been reported capable of treating 2 t/ha of soil contaminated with PCBs and has succeeded treat 11,700 tons of soil at PCBs levels as high as 2000 ppm to arrive at a final concentration less than 0.5 ppm (Naval Facilities Engineering Service Center, 1997).
Similar to the glycolate dehalogenation process, the limiting factors of base-catalyzed decomposition are soil humidity, acidity, clay content and soil organic matter. In addition, salt formation is also reducing the performance of any dehalogenation process.
In order to carry out dehalogenation of POPs using the base-catalyzed method several types of base are possible to be used such as carbonates, bicarbonates and hydroxide of alkali or alkaline metals. The most used metals are sodium and potassium (Zinoviev et al., 2007; Akhondi and Dadkhah, 2018). As the dehalogenation process includes detachment of halogens from the parent molecule, then donor proton is required to substitute the removed halogens. A number of donor proton may be used, such as high boiling mineral oil, aliphatic alcohol or amine.
Although base-catalyzed decomposition is a method for detoxification of persistent organic pollutants (POPs) that has been thoroughly studied, trialled and well-established knowledge, however, little research has focused on the destruction of chlorinated new POPs instead of dirty dozen POPs as
described in the initial list of pollutants of Stockholm Convention (UNEP, 2009; Huang, 2015).
Furthermore, the use of metal alkalies such as sodium and potassium in the forms of oxides, hydroxides or organometallics predominates instead of the alkaline earth metals, e.g. calcium.
Potential use of the calcium-based catalyst for the decomposition of POPs
It has been stated that metals of alkali and alkaline earth both are suitable for the decomposition of POPs (McDowall, 2002; McDowall and Vijgen, 2002;
McDowall et al., 2004; Zinoziev et al., 2007).
Surprisingly, the use of sodium and potassium metals has been studied thoroughly, leaving the use of metals of the alkaline earth group that is still lacking.
Indonesia has a huge amount of calcium natural resource deposits, one of the alkaline earth group members, of around 2.16-28.7 billion tons (Aziz, 2010; Dewanto et al., 2013). Naturally, natural calcium resources existed in the form of limestone deposits that mainly is consisted of calcite (CaCO3) and dolomite (MgCO3) minerals. The proportion of the two minerals is variously dependent on location. For Indonesian limestone, the proportion of calcite almost exclusively exceeded dolomite, i.e. more than 50%, at most sites of Indonesian limestone natural resource deposits (Sukandarrumidi, 2009). Karst topography, a source of limestone, can be found in large parts of the Indonesian landscape, as shown in Figure 9 (Ministry of Energy and Mineral Resources Republic of Indonesia, 2014).
There are wide applications of materials that are based on or synthesized from limestone, such as building construction, cement production, chemicals for food and agriculture up to the peculiarly synthesized matters such as nanomaterials for cosmetics, drugs and pharmaceuticals as well as catalysts (Harder, 2010; Suprapto et al., 2016; Centre for Industry Education Collaboration, 2017; Fitriani et al., 2017). Worldwide use of limestone was 60%
metallurgy, 25% construction and 15% chemical, industrial and environmental uses (Centre for Industry Education Collaboration, 2017). Figure 10 presents the diverse applications of limestone-based materials (Centre for Industry Education Collaboration, 2017).
Considering such a huge amount of calcium deposit is available in Indonesia, then it should be worth substituting the use of sodium or potassium- based catalysts to handle POPs problems such as the remediation of environmental matrices contaminated with POPs or annihilation stock of banned halogenated pesticides. Although the use of calcium-based reagents to decontaminate or destroy materials containing POPs has been known since more than three decades ago, however, the development of technology based on calcium still far behind those based on sodium or potassium. Despite the abundance of sodium and potassium resources in developed countries, probably,
Open Access 3426 such late development of calcium-based technology
for POPs destruction resulted from more obvious chemical reactivity of sodium and potassium compared to calcium. Nonetheless, the use of calcium- based catalysts (e.g. oxides, ethoxides, methoxides or glyceroxides) for other purposes such as transesterification (Kouzu et al., 2008; Liu et al., 2008;
Correira et al., 2014; Aqliliriana et al., 2015;
Marinkovic et al., 2016; Longwitz et al., 2017;
Esipovich et al., 2018; Mehta et al., 2018) are more
common than dehalogenation reactions, particularly for POPs destruction. Perhaps the most confounding in POPs destruction using heterogeneous calcium-based catalyst is differentiating whether the process is accomplished through adsorptive characteristics or catalytic features of the solid surface. Failure to recognize the characteristics will make the POPs destruction proceed with little success. Thus controlled engineering of raw materials containing calcium to produce expected characteristics is required.
Figure 9. Limestome sources map of Indonesia.
Figure 10. Diverse application of limestone-based materials.
Conclusion
Persistent organic pollutants are xenobiotics of environmental concerns. Their presence in the environment may endanger living organisms, including humans. They are ubiquitous and may be
present in the atmosphere, water, soil, including agricultural soils. Incineration provided the most rapid method to remediate soil contaminated with POPs.
However, carbon dioxide emission to the atmosphere might hinder the implementation of incineration of POPs. Another method, i.e. base-catalyzed
Open Access 3427 decomposition, potentially provided a more
appropriate method for POPs decomposition. As Indonesia is rich in natural limestone deposits, the use of calcium-based catalyst to enhance base-catalyzed decomposition is potentially more suitable to be applied rather than sodium and potassium-based catalysts. Further study is needed in order for synthesizing proper catalysts based on calcium to alleviate POPs pollution in Indonesia.
References
Adeyemo, A.A., Adeoye, I.O. and Bello, O.S. 2012. Metal organic frameworks as adsorbents for dye adsorption:
overview, prospects and future challenges. Toxicological
& Environmental Chemistry 94:1846-1863, doi:10.1080/02772248.2012.744023.
Agapkina, G.I., Brodskiy, E.S., Shelepchikov A.A. and Artukhova A.M. 2017. Transformation and form of dichlorodiphenyltrichloroethane applied to Moscow soils. Moscow University Soil Science Bulletin 72(3):125-131
Akhondi, M. and Dadkhah A.A. 2018. Base-catalysed decomposition of polychlorinated biphenyls in transformer oils by mixture of sodium hydroxide, glycerol and iron. Royal Society Open Science 5:172401, doi:10.1098/rsos.172401.
Ang, E.L., Zhao, H. and Obbard, J.P. 2005. Recent advances in the bioremediation of persistent organic pollutants via biomolecular engineering. Enzyme and Microbial
Technology 37:487-496,
doi:10.1016/j.enzmictec.2004.07.024.
Aqliliriana, C.M., Ernee, N.M. and Irmawati, R. 2015.
Preparation and characterization of modified calcium oxide from natural resources and their application in transesterification of palm oil. International Journal of Scientific & Technology Research 4(11):168-175.
Aziz, M. 2010. Limestone: added value improvement and specification for industries. Jurnal Teknologi Mineral dan Batubara 6(3):116-131 (in Indonesian).
Azrague, K. and Osterhus S.W. 2009. Persistent organic pollutants (POPs) degradation in natural waters using a V-UV/UV/TiO2 reactor. Water Science and Technology:
Water Supply 9(6):653-660.
Baran, W., Makowski, A. and Wardas, W. 2008. The effect of UV radiation absorption of cationic and anionic dye solutions on their photocatalytic degradation in the presence TiO2. Dyes and Pigments 76(1):226-230, doi:10.1016/j.dyepig.2006.08.031.
Berger M. No Year. What is a MOF (metal organic
framework)?. Available from
https://www.nanowerk.com/mof-metal-organic- framework.php.
Brodskiy E.S., Shelepchikov A.A., Feshin D.B., Agapkina G.I. and Artukhova M.V. 2016 Content and distribution pattern of dichlorodiphenyltrichloroethane (DDT) in soils of Moscow. Moscow University Soil Science Bulletin 71(1):27-34.
Centre for Industry Education Collaboration. 2017. The Essential Chemical Industry Online – calcium carbonate. Department of Chemistry. University of York. York. UK.
Collings A.F., Farmer A.D., Gwan P.B., Pintos A.P.S. and Leo D.J. 2006. Processing contaminated soils and
sediments by high power ultrasound. Mineral Engineering 19:450-453.
Correia, L.M., Saboya. R.M.A., Campelo, N.S., Cecilia.
J.A., Castellon, E.R-., Cavalcante. C.L. Jr. and Vieira, R.S. 2014. Characterization of calcium oxide catalysts from natural sources and their application in the transesterification of sunflower oil. Bioresource
Technology 151:207-213,
doi:10.1016/j.biortech.2013.10.046.
Cravotto, G. and Cintas, P. 2012. Introduction to sonochemistry: a historical and conceptual overview. In:
Chen, D., Sharma, S.K. and Mudhoo, A. (Eds.) Handbook on Applications of Ultrasound – Sonochemistry for Sustainability. CRC Press. USA. 23- 40.
de Mendonça, V.R., Lopes O.F., Fregonesi, R.P., Giraldi, T.R. and Ribeiro, C. 2014. TiO2-SnO2 heterostructures applied to dye photodegradation: The relationship between variables of synthesis and photocatalytic performance. Applied Surface Science 298:182-191.
Dewanto, D.P., Fransiskus, Wibisono, H.Y., Adnan, I.F. and Haidar, M. 2013. Report of Project Planning on Exploration of Lime Stone Deposition Mining. Faculty of Mining and Petroleum Engineering. Bandung Institute of Technology (in Indonesian).
Doll, T.E. and Frimmel, F.H. 2005. Removal of selected persistent organic pollutants by heterogeneous photocatalysis in water. Catalysis Today 101(3-4):195- 202, doi:10.1016/j.cattod.2005.03.005.
Dong, H., Zeng, G., Tang, L., Fan, C. Zhang, C., He, X. and He, Y. 2015. An overview on limitations of TiO2-based particles for photocatalytic degradation of organic pollutants and the corresponding countermeasures.
Water Research 79:128-146.
Environment Australia. 1997. Appropriate Technologies for the Treatment of Scheduled Wastes: Review Report Number 4. Department of the Environment, Water, Heritage and the Arts. Australian Government.
Australia.
Esipovichk, A., Rogozhin, A., Danov, S., Beleusov, A. and Kanakov, E. 2018. The structure, properties and transesterification catalytic activities of the calcium glyceroxide. Chemical Engineering Journal 339:303- 316.
Fitriani, K.C., Taufik, D., Wahyudi, K. and Hernawan. 2017.
Synthesis of precipitated calcium carbonated with acid stearat as a surface modifier. Jurnal Keramik dan Gelas Indonesia 2(2):87-95 (in Indonesian).
Flores, R., Blass, G. and Dominguez, V. 2007. Soil remediation by an advanced oxidative method assisted with ultrasonic energy. Journal of Hazardous Materials 140:399-402, doi:10.1016/j.jhazmat.2006.09.044.
Garcia, H. and Ferrer, B. 2013. Photocatalysis by MOFs. In:
Xamena, F.X.L. and Gascon, J. (Eds.). Metal Organic Frameworks as Heterogeneous Catalyst. RSC Publishing. Cambridge. UK. 365-383.
Han, D., Li, Y. and Jia, W. 2010. Preparation and characterization of molecularly imprinted SiO2-TiO2 and photo-catalysis for 2, 4-dichlorophenol. Advanced Materials Letters 1(3):188-192.
Harder, S. 2010. From limestone to catalysis: application of calcium compounds as homogeneous catalysts.
Chemical Review 110:3852-3876.
Herlambang, A., Sudaryanto, A., Mulyanto, A. And Aviantara, D.B. 2015. Destruction Technology for PCBs
Open Access 3428 (Teknologi Destruksi PCBs). Research Report. Pusat
Layanan Teknologi – BPPT (in Indonesian).
Huang, H., Jiang, J.G., Xiao Y. and Song, Y.C. 2015. Lab and pilot scale studies of chlorinated new POPs destruction using base-catalyzed dechlorination method.
China Environmental Science 35(4):1149-1155.
Jimenez, J.C., Dachs, J. and Eisenreich, S.J. 2015.
Atmospheric deposition of POPs: implications for the chemical pollution of aquatic environments.
Comprehensive Analytical Chemistry 67:295-322.
Kang SH, Lee W. and Kim H.S. 2012. Effects of CdS sensitization on single crystalline TiO2 nanorods in photoelectrochemical cells. Material Letters 85:74-76.
Kouzu, M., Kasuno, T., Tajika, M., Sugimoto, Y., Yanamaka, S. and Hidaka, J. 2008. Calcium oxide as a solid base catalyst for transesterification of soybean oil and its application to biodiesel production. Fuel 7(12):2798-2806.
Kovner, K. 2017 Persistent Organic Pollutants: A Global Issue, A Global Response. Available at https://www.epa.gov/international-
cooperation/persistent-organic-pollutants-global-issue- global-response (retrieved on 19 April 2019).
Lei, Z. 2015. Fate of POPs and its laboratorial technics under combined plants cultivation. Advanced Materials Research 1065-1069:3146-3150.
Levec, J. and Pintar, A. 2007. Catalytic wet-air oxidation processes: A review. Catalysis Today 124:172-184.
Li, F. 2012. Study on sono-photocatalytic degradation of POPs: A case study hydrating polyacrylamide in wastewater. In: Puzin, T. and Szlichtyng, A.M (Eds).
Organic Pollutants Ten Years After the Stockholm Convention – Environmental and Analytical Update.
InTech. Croatia. 327-344.
Li, Y., Wang, H., Zhang, J., Wang, J. and Miao, W. 2012 The industrial practice of POPs contaminated soil as alternative raw materials in clinker production. Procedia Environmental Sciences 16:641-645.
Liu, X., Piao, X., Wang, Y. and Zhu, S. 2008. Calcium ethoxide as a solid base catalyst for the transesterification of soybean Oil to biodiesel. Energy &
Fuels 22(2):1313-1317.
Longwitz, L., Steinbauer, J., Spannenberg, A. and Werner, T. 2017. Calcium-based catalytic system for the synthesis of bio-derived cyclic carbonates under mild conditions. American Chemical Society (ACS) Catalysis 8(1):665-672.
Lukic, B., Panico, A., Huguenot, D., Fabbricino, M., van Hullebusch, E.D. and Esposito, G.2017. A review on the efficiency of landfarming integrated with composting as a soil remediation treatment. Environmental Technology Review 6(1):94-116.
Luo, J. and Lei, Z. 2014. Enhanced dissipation of POPs in soils by combined plants cultivation. Applied Mechanics and Materials 675-677:416-421.
Mahlambi, M.M., Ngila, C.J. and Mamba, B.B. 2015. Recent developments in environmental photocatalytic degradation of organic pollutants: The case of titanium dioxide zanoparticles-A review. Journal of Nanomaterials 2015:1-29.
Mahmiani, Y., Sevim, A.M. and Gul, A. 2016.
Photocatalytic degradation of persistent organic pollutants under visible irradiation by TiO2 catalysts sensitized with Zn(II) and Co(II) tetracarboxy- phthalocyanines. Journal of Porphyrins Phthalocyanines 20:1190–1199.
Manuaba, I.B.P. 2007. Chlorinated organic pesticide contaminants in Buyan Lake Buleleng Bali. Jurnal Kimia 1(1):39-46 (in Indonesian).
Marinković, D.M., Stankovic, M.V., Velickovic, A.V., Avramović, J.M., Miladinović, M.R., Stamenković, O.O., Veljković, V.B. and Jovanović, D.M. 2016.
Calcium oxide as a promising heterogeneous catalyst for biodiesel production: Current state and perspectives.
Renewable and Sustainable Energy Reviews 56:1387- 1408.
McDowall, R. 2002. Destruction and Decontamination Technologies for PCBs and other POPs Wastes Under the Basel Convention: A training manual for hazardous waste project managers. Vol. A. Secretariat of the Basel Convention. International Environment House.
Switzerland.
McDowall, R. and Vijgen, J. 2002. Destruction and Decontamination Technologies for PCBs and other POPs Wastes Under the Basel Convention: A training manual for hazardous waste project managers. Vol. C- Annexes. Secretariat of the Basel Convention.
International Environment House. Switzerland.
McDowall, R., Boyle, C., Graham, B. 2004. Review of Emerging, Innovative Technologies for the Destruction and Decontamination of POPs and the Identification of Promising Technologies for Use in Developing Countries. The Scientific and Technical Advisory Panel of the GEF United Nations Environment Programme and International Centre for Sustainability Engineering and Science, Faculty of Engineering, The University of Auckland, Auckland, New Zealand.
Megharaj, M. and Naidu, R. 2017. Soil and brownfield bioremediation. Microbial Biotechnology 10(5):1244- 1249
Mehta, K., Jha, M.K. and Divya, N. 2018. Transesterification of Prunus armeniaca oil using calcium methoxide as a catalyst: Identification of methyl esters and proposed mechanistic pathways. Energy Sources Part A:
Recovery, Utilization, and Environmental Effects 40(19):2317-2326.
Melnikova, T.V., Polyakova, L.P., Gordeev, A.V. and Oudalova, A.A. 2019. Radiation stability of lindane and active substance of hexachlorane dust preparation under electron irradiation. IOP Conference Series: Materials Science and Engineering 487:1-5.
Ministry of Energy and Mineral Resources Republic of Indonesia. 2014. Map of Indonesian Limestone Distribution. Indonesian Geological Agency (in Indonesian).
Ministry of Environment Republic of Indonesia. 2014.
Review and Update of National Implementation Plan for Stockholm Convention on Persistent Organic Pollutants in Indonesia. Ministry of Environment Republic of Indonesia.
Nahas, A.C. 2009. Global distribution of persistent organic pollutants (POPs). Bukit Koto Tabang Global Atmospheric Monitoring Station. Meteorology Climatology and Geophysics Council (in Indonesian).
Naval Facilities Engineering Service Center. 1997.
Technology Transfer Report: Production Base Catalysed Decomposition Process, Guam, Mariana Islands (Technical Report: TR-2075-ENV). Port Hueneme.
California. United States.
Pariatamby, A. and Kee, Y.L. 2016. Persistent organic pollutants management and remediation. Procedia Environmental Sciences 31:842-848.
Open Access 3429 Pi, Y., Li, X., Xia, Q., Wu, J., Li, Y., Xiao, J. and Li, Z. 2017.
Adsorptive and photocatalytic removal of persistent organic pollutants (POPs) in water by metal-organic frameworks (MOFs). Chemical Engineering Journal 337:351-371.
Pusarpedal (Center for Environmental Impact Management Facilities). 2014. Monitoring and Study of Organic Pollutants in the Environment Year 2014. Available at http://www.kelair.bppt.go.id/sib3pop/Iptek/Pemantauan POP2014/PemantauanPOP2014.htm (retrieved on 13 March 2019) (in Indonesian).
Rahuman, M.S.M.M., Pistone, L., Trifiro, F. and Miertus, S.
2000. Destruction technologies for polychlorinated biphenyls (PCBs). Proceedings of Expert Group Meetings on POPs and Pesticide Contamination:
Remediation Technology and on Clean Technologies for The Reduction and Elimination of POPs. ICS-UNIDO.
Santoso, W.Y. 2009. The urgency for the ratification of the 2001 Stockholm Convention on Persistent Organic Pollutants for Indonesia. Mimbar Hukum 21(1):53-66 (in Indonesian).
Secretariat of the Stockholm Convention. 2019. Ninth Meeting of the Conference of the Parties to the Stockholm Convention. Available at http://chm.pops.int/TheConvention/
ConferenceoftheParties/Meetings/COP9/tabid/
7521/Default.aspx (retrieved on 19 April 2019).
Shammi, M., Uddin, M.K., Malek, M.A. and Hasanuzzaman, M. 2007. Degradation of DDT by gamma-radiation in perspective of POPS management in Bangladesh.
Journal of Agricultural Education and Technology 10(1- 2):15-20.
Shoiful, A., Fujita, H., Watanabe, I. and Honda, K. 2013.
Concentrations of organochlorine pesticides (OCPs) residues in foodstuffs collected from traditional markets in Indonesia. Chemosphere 90:1742-1750.
Shresta, R.A., Mudhoo, A., Pham, T.D. and Sillanpaa, M.
2012. Ultrasound and sonochemistry in the treatment of contaminated soils by persistent organic pollutants. In:
Chen, D., Sharma, S.K. and Mudhoo, A. (Eds.) Handbook on Applications of Ultrasound – Sonochemistry for Sustainability. CRC Press. USA. 407- 418.
Sinulingga, K. 2006. Study of organochlor residues on Daucus carota L. carrots in the central district of Karo Regency, North Sumatra. Jurnal Sistem Teknik Industri 7(1):92-97 (in Indonesian).
Sorescu, M. and Xu, T. 2011. The effect of ball-milling on the thermal behavior of anatase-doped hematite ceramic system. Journal of Termal Analysis and Calorimetry 103(2):479-484.
Speight, J.G. 2017.Environmental Organic Chemistry for Engineers. Elsevier Inc. India.
Suharsih, Sudarto, Wihardjaka, A., Dewi, T., Sukarjo, Pramono, A., Wahyuni, S., Ariani, M. and Suryanto .2015. Annual Report 2015. Agricultural Environmental Research Institute. Agricultural Research and Development Agency. Ministry of Agriculture, Republic of Indonesia (in Indonesian).
Sukandarrumidi. 2009. Industrial Mining Materials. Gadjah Mada University Press. Yogyakarta. Indonesia (in Indonesian).
Sumartono, A. 2002. Decomposition of Pentachlorophenol in Water by Gamma Irradiation. Master Thesis, Bogor Agricultural University (in Indonesian).
Sun, M., Li, D., Chen, Y., Chen, W., Li, W., He, Y. and Fu, X. 2009. Synthesis and photocatalytic activity of calcium antimony oxide hydroxide for the degradation of dyes in water. Journal of Physical Chemistry C 113(31):13825- 13831.
Suprapto, Fauziah, T.R., Sangi, M.S., Oetami, T.P., Qoniah, I. and Prasetyoko, D. 2016. Calcium oxide from limestoneas soild base catalyst in transesterification of Reutealis trisperma oil. Indonesian Journal of Chemistry 16(2):208-213.
The GTZ-Holcim Public Private Partnership. 2013.
Guidelines on co-processing Waste Materials in Cement Production. Holcim Group Support Ltd and Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH.
Trifan, A. and Calinescu, I. 2009. Microwave assissted catalytic dechlorination of PCB. University Politehnica of Bucharest Scientific Bulletin 71(4):71-80.
Ulgen, A. and Hoelderich, W.F. 2011. Conversion of glycerol to acrolein in the presence of WO3/TiO2
catalysts. Applied Catalysis A: General 400(1-2):34-38.
United Nations Environment Programme (UNEP). 2012.
Technical Guidelines on the Environmentally Sound Co- processing of Hazardous Waste in Cement Kilns.
Secretariat of the Basel Convention. International Environment House. Switzerland.
United Nations Environment Programme (UNEP).2009. The Nine New POPs: an introduction to the nine chemicals added to the Stockholm Convention by the Conference of the Parties at its fourth meeting. Secretariat of the Stockholm Convention on Persistent Organic Pollutants.
International Environment House. Switzerland.
United States Environmental Protection Agency (USEPA).
2017. Overview of wood preservative chemicals.
Available at https://www.epa.gov/ingredients-used- pesticide-products/overview-wood-preservative- chemicals (retrieved on 4 April 2019).
Verma, A. K., Dash, R.R. and Bhunia, P. 2012. A review on chemical coagulation/flocculation technologies for removal of colour from textile wastewaters. Journal of Environmental Management 93(1):154-168.
Wang, C.C., Li, J.R., Lv, X.L., Zhang, Y.Q. and Guo, G.
2014. Photocatalytic organic pollutants degradation in metal–organic framework. Energy & Environmental Science 7(9):2831-2867.
Winarti, C. and Munarso, S.J. 2005. Study of dioxin contamination in food. Proceedings of the National Seminar on Postharvest Innovative Technologies for the Development of Agriculture-Based Industries. Center for Agricultural Research and Development. Agriculture Department. Bogor, Indonesia 1208-1217 (in Indonesian).
Zacharia, J.T. 2019. Degradation pathways of persistent organic pollutants (POPs) in the environment. In: S.K.
Donyinah, S.K (Ed), Persistent Organic Pollutants.
InTechopen 17-29.
Zeng, L., Guo, X., He, C. and Duan, C. 2016. Metal-organic frameworks: versatile materials for heterogeneous photocatalysis. ACS Catalysts 6(11):7935-7947.
Zinoviev, S., Fornasiero, P., Lodolo, A. and Miertus, S.
2007. Non-combustion technologies for POPs destruction: review and evaluation. International Centre for Science and High Technology. United Nations Industrial Development Organisation, Pure and Applied Chemistry, Trieste, Italy.
