Recycling Waste Paper for Further Implementation: XRD, FTIR, SEM, and EDS Studies

(1)

See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/359205453

Recycling Waste Paper for Further Implementation: XRD, FTIR, SEM, and EDS Studies

Article in Journal of Oleo Science · January 2021

DOI: 10.5650/jos.ess21396

CITATIONS

9

READS

197

5 authors, including:

Sarita Manandhar University of Tsukuba 3PUBLICATIONS 16CITATIONS

SEE PROFILE

Flavien Sciortino University of Basel 26PUBLICATIONS 232CITATIONS

SEE PROFILE

Katsuhiko Ariga

National Institute for Materials Science 1,130PUBLICATIONS 57,626CITATIONS

SEE PROFILE

Lok Kumar Shrestha

National Institute for Materials Science 239PUBLICATIONS 8,252CITATIONS

SEE PROFILE

All content following this page was uploaded by Sarita Manandhar on 09 December 2023.

The user has requested enhancement of the downloaded file.

(2)

619 J. Oleo Sci. 71, (4) 619-626 (2022)

Recycling Waste Paper for Further Implementation:

XRD, FTIR, SEM, and EDS Studies

Sarita Manandhar

¹

, Bindra Shrestha

^1＊

, Flavien Sciortino

^2,3

, Katsuhiko Ariga

^2,4

, and Lok Kumar Shrestha

^2＊

1 Department of Chemistry, Tri-Chandra Multiple Campus, Tribhuvan University, Kathmandu 44600, NEPAL

2 International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044, JAPAN

3 Université Grenoble Alpes, Département de Chimie Moléculaire, UMR-5250, 38041 Grenoble Cedex 9, FRANCE

4 Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, JAPAN

1 Introduction

Recycling is one of the best ways to reduce waste production and management, mitigate the environment, and improve the world s economy. Over the last few decades, there has been a growing interest in recycling technology in the industry to develop new materials from renewable sources and is advantageous for sustainable developments^1−3）. Recycling reduces the cost, energy, resources, and pollu- tions and contributes to extending the used materials life and usefulness. Therefore, it has considerable social importance. Recycling prevents the wastage of potentially valuable materials and reduces the consumption of fresh raw materials. Several countries in the world are strongly committed to recycling different waste materials. Europe is committed to recycling plastics, especially packaging. Simi- larly, China has established a market-driven paper recycling

＊Correspondence to: Lok Kumar Shrestha, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044, JAPAN

E-mail: [email protected]

Accepted January 11, 2022 (received for review November 30, 2021) Journal of Oleo Science ISSN 1345-8957 print / ISSN 1347-3352 online http://www.jstage.jst.go.jp/browse/jos/ http://mc.manusriptcentral.com/jjocs

system. USA and Japan are recycling several tens of million tons of recovered papers（generally refers to the used paper re-covered for use as raw material）to manufacture the new paper and paperboard^4）.

Recycling involves collecting and separating waste materials and remanufacturing or converting them into new reusable materials. Almost everything around us can be recycled or necessary functional materials can be prepared from waste. For example, nanoporous activated carbon materials have been successfully fabricated from agricul- tural lignocellulosic wastes and explored in high energy- storage supercapacitor as well as water purification applications^5−10）. Cellulose, which is mostly used in the paper industry, is one of the essential components of the lignocellulosic agro-wastes suggesting that used or waste papers would be the valuable reusable source that can be recycled Abstract: Recycling technology contributes to sustainability and has received considerable interest in fulfilling consumable products’ social demands, including papers. Recycled fibers are the primary source of the papermaking industry. Papers, valuable daily used materials, can be further recycled for further implementation. Here, we report a simple method for recycling waste papers for further use. Our method includes re-pulping, deinking, bleaching, and papermaking. The sample and the recycled papers were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). XRD data shows the presence of cellulose and filler minerals in the sample and the recycled papers. FTIR analysis confirmed the presence of hydroxyl, carbonyl, and methyl functional groups in the recycled papers suggesting that the deinking and bleaching did not cause any structural changes. The fibrous structures were also sustained after recycling, as confirmed by SEM studies demonstrating that the recycling was successful and the papers can be further used and recycled. EDS analysis further confirmed the filler minerals in the sample paper with a trace amount of lead, which decreased upon bleaching the paper. The structure and properties of the sample and the recycled papers were quite similar, inferring that waste papers can be recycled again and different products from low to higher grade papers can be fabricated.

Key words: paper recycling, re-pulping, deinking, bleaching, cellulose fibers

(3)

S. Manandhar, B. Shrestha, F. Sciortino et al.

J. Oleo Sci. 71, (4) 619-626 (2022) 620

and new functional materials can be prepared. Lei and co- workers have recently reported a new approach to recycle office waste paper^11）. They have successfully extracted cellulose nanocrystals from the office waste paper and then used them as the organic filler to reinforce polyurethane elastomer, which resulted in better thermal and thermos- mechanical properties of the polyurethane.

Investigations have shown that about 90％ of the total pulp used for making paper and paperboard is wood pulp inferring wood as the world s only renewable natural resources^12）. Other resources are fiber crops, waste papers, rags, artificial fiber, etc. Recycled fiber has also become a major source of papermaking fibers in many regions of the world. The pulp, which contains three primary components; cellulose fibers, lignin, and hemicelluloses, can be manufactured by mechanical and chemical methods, and the product may be either bleached or non-bleached, depending on the customer s requirements. Over 50 grades of waste papers have been identified. During the paper recycling process, various types of papers are treated in different ways to produce different recycled paper products^13）. Successful recycling requires clean recovered paper, which is necessary to keep paper free from contaminants, including heavy metals, plastics, dirt, ink, toners, dyes, coatings, fillers, papermaking additives, etc.^14）.

In this contribution, a simple method for recycling waste paper is reported. The recycling method includes, deinking, bleaching and papermaking. The recycled papers（re- pulped paper: RP, deinked paper: DP, and bleached paper:

BP）and sample paper（SP）were well characterized by XRD, FTIR, SEM, and EDS techniques. In addition, different physical parameters, including grammage, bulk, moisture content, water absorption, Kappa number, were determined. The recycled papers were found to be of good quality without any physical and chemical degradation of the fiber structures, demonstrating that waste papers can be recycled using our straightforward method for further implementation.

2 Materials and Methods

2.1 Recycling of waste paper and papermaking

Used writing paper waste（250 g）was soaked in distilled water（2000 mL）for 2 days and re-pulped on a mechanical grinder. About 98％ of the pulp was recovered, which was then divided into three parts. One part was kept separately to make re-pulped paper, and two parts of pulp were mixed with detergent（50 g）and water（250 mL）and left for 24 hours for deinking. Deinked pulp was washed with water

（500 mL）about 10 times to remove the ink particles sepa- rated from the pulp during deinking. The yield of the deinked paper was estimated to be 〜96％. Next, deinked pulp was again divided into two parts. Deinked paper was

prepared from one part while the other part of the pulp was mixed with bleaching powder（7 g）and water（250 mL）

and left for 24 hours to bleach the pulp. Then, the bleached pulp was washed with distilled water 7 times to remove the bleaching powder. Each time 1000 mL water was used for washing. Due to the multiple washing, some materials were lost and the yield of the bleached pulp was estimated to be

〜94％. Finally, the bleached pulp was used to make paper.

Thus, three different papers, re-pulped, deinked, and bleached, were made from the used writing paper. The prepared papers are referred to as RP（re-pulped）, DP

（deinked）, and BP（bleached）. For comparison, unused referred to as the sample paper（SP）, was also considered, and their physical properties were investigated.

For papermaking, a circular sieve was placed in a vessel filled up with water（1500 mL）and two tablespoons of thick consistency pulp were added to the sieve and distributed uniformly by hand. The sieve was taken out of the water slowly and dried under the sunlight. Once the paper was dried completely, it was taken out of the sieve and stored between the folds of papers.

2.2 Estimation of basis weight（grammage）

The recycled papers（RP, DP, and BP）and the sample paper（SP）were cut into a circular shape and weighted separately. The radius of the papers was measured and the area of each paper was determined. Basic weight（Gram- mage）was calculated as^15）:

Grammage＝weight / area （1）

2.3 Bulk

The thickness of the paper was measured by using a mi- crometer screw gauge, and the bulk of the paper was estimated as:

Bulk＝thickness / grammage （2）

2.4 Moisture content

The weight of wet and dried papers was weighed out to determine the moisture content. The paper was dried at 80℃ in a hot-air oven for 10 min. The moisture content of papers was estimated as:

Moisture content＝W−w /W×100％（3）

Where W and w represents weight of paper before and after drying, respectively.

2.5 Water absorption

Water absorption was estimated by weighing the amount of water absorbed by the paper at different intervals of time until one hour. The weight of the paper was first measured, and the paper was placed in a beaker containing water（150 mL）. Next, the weight of the wet paper was

(4)

621 measured at different intervals of time（5–60 min）. Before

weighing, the excess water on the paper was removed by suspending the paper in the air. After weighing, the paper was again soaked in water.

2.6 Kappa number

Kappa number was identified titrimetrically. For the identification of kappa number, the tests were carried out with and without samples as follows: First of all, the dry paper was weighed, soaked in a 1000 mL beaker containing distilled water, and left overnight to make it pulp again by disintegration. Then, distilled water was added to make the volume 500 mL. In a separate beaker, H2SO4 solution（100 mL）and KMnO4 solution（100 mL）were correctly mixed and added to the beaker containing pulp. The mixture was left for 10 mins, and KI solution（20 mL）was added to stop the reaction. Immediately after, the free iodine was titrated against Na2S2O3 solution by adding a few drops of the starch solution as an indicator at the end of the reaction.

The endpoint is detected when the mixture turns white.

The exact process was carried out for the blank test without the pulp. The Kappa number（K）, which is the volume of 0.1 N KMnO4 solution consumed by one gram of the moisture-free paper, was calculated as^16）:

K＝p× f / w p＝（b−a）N / 0.1 （4）

Where, p, f, and w, respectively indicate the amount of 0.1 N KMnO4 solution consumed（mL）, correlation factor, the weight of pulp（g）and a, and b represent the amount of thiosulfate consumed by the test specimen（mL）and blank solution, respectively. The KMnO4 solution is consumed due to reaction with lignin and other oxidized compounds within a given time;

MnO4−＋8H^＋→Mn^2＋＋4H2O MnO4−＋4H^＋→nO2＋2H2

The excess volume of KMnO4 solution is measured by ti- trating with the standard thiosulfate solution after adding an excess of potassium iodide.

2MnO4−＋10I⁻＋16H^＋→2Mn^2＋＋5I2＋8H2O

MnO2＋4H^＋＋2I⁻→Mn^2＋＋2H2O＋I2

2S2O32−＋I2→S4O62−＋2I⁻ 2.7 Characterization

The sample paper and the recycled papers were characterized by scanning electron microscopy（SEM: Hitachi S-4800, Hitachi Co., Ltd. Tokyo, Japan, operated at 10 kV and 10 µA）, X-ray diffraction（XRD: Rigaku X-ray diffrac- tometer, RINT, Tokyo, Japan, operated at 40 kV and 40 mA with Cu-Kα radiation）, and Fourier-transformed infrared

（FTIR）spectroscopy using ATR method on a Nicolet 4700

（Thermo Electron Corporation）. In addition, energy-dispersive X-ray spectroscopy（EDS）analyses were carried out on the sample paper and the recycled papers using a Horiba Model EMAX 7593-H accessory interfaced with a Hitachi S-4800 SEM instrument.

3 Results and Discussion

3.1 Basis weight（grammage）, bulk, moisture content and Kappa number

Basis weight（grammage）, bulk, and moisture content of the sample paper and the re-cycled papers（RP, DP, and BP）were estimated and summarized in Table 1.

The grammage of the recycled papers ranges from 10.483 to 13.296 g/m², while the grammage of the sample paper is ca. 50.552 g/m². Generally, the basis weight of the papers ranges from 40-120 g/m^{2 17）}. For tissue papers, the basis weight is less than 40 g/m^{2 18）}. The observed lower basis weight of the recycled papers compared to the grammage of the sample paper can be attributed to the lower fiber consistency in the recycled papers. Judging from the basis weight, it can be concluded that the waste paper can be recycled to make tissue papers, envelopes, or any other materials of low grade but cannot be recycled back to the writing grade paper^18）. To make the writing grade paper, virgin fibers can be added to increase quality and strength during the recycling process.

The measurement of the bulk of the paper is of importance to publishers and bookbinders. Bulk value often de- Table 1　 General physical parameters of the sample and the recycled papers: Basis

weight, bulk and moisture content of the sample and the recycled papers.

Paper Grammage

(g/m²) Bulk (cm³/g) Moisture content

(%) Kappa number

SP 50.552 1.384 11.12 32.60

RP 10.483 1.240 5.96 24.09

DP 10.173 1.180 4.26 42.66

BP 13.296 1.128 5.72 41.38

(5)

J. Oleo Sci. 71, (4) 619-626 (2022) 622

termines what type of printers can handle the paper and decides beforehand how thick a book or magazine will be.

Bulk measures thickness to its weight in cubic centimeters per gram. Since the pulp is homogeneously distributed while making the papers, weight determines the thickness of the paper, inferring that a paper having more weight is thicker than the paper with low weight. For the pulp sheet, the bulk is found to be 1.64 cm³/g, and for the tissue papers, the bulk ranges from 2-4 cm³/g^{17, 18）}. Presently, the bulk of our recycled papers is found in the range of 1.128 to 1.240 cm³/g, while the bulk of sample paper is estimated to be 1.384 cm³/g suggesting that the recycled papers have lower bulk compared to the sample paper. The decrease in the bulk makes the paper smoother, less opaque, and lower in strength.

The moisture content of all the grades of the papers is found in the range of 2-12％^{3, 18, 19）}. Our sample paper contains 11.13％ moisture, while the moisture content of the recycled papers is lower and found in the range of 4.26- 5.96％. The higher moisture content on the sample paper may be because the sample paper was stored in a room for a longer period. Long-term paper storage absorbs moisture from the atmosphere. Similarly, the recycled papers were stored properly between the folds of the copy, causing a lower moisture content. The moisture content of the recycled papers lies in the range of moisture content of the tissue papers, which is reported in the ranges from 2-7％^19）. Poor moisture control can adversely affect several properties of paper, demonstrating the importance of moisture control in papermaking.

The Kappa number, which is related to the lignin content of the pulp, is an important parameter of the papers and it estimates the amount of chemical essential during bleaching of the wood pulp so that pulp with a required degree of whiteness can be obtained. Generally, the Kappa number of pulps ranges from 1-100 depending on the lignin content in the pulp^20）. Also, for the bleachable pulp, the Kappa number is found to be of 25-30. The Kappa number of the sample paper is ca. 32.60 while it is found in the range of 24.09- 42.66 for the recycled papers（24.09 for RP, 42.66 for DP, and 41.38 for BP）. The sample s smaller Kappa value and re-pulped papers suggest less lignin content in the pulp used during the paper making. The increased Kappa value of the deinked paper compared to re-pulped paper may be due to the interference of the ink on paper while deinking. The Kappa number of the bleached paper is com- parable to the deinking paper.

3.2 Water absorption

Figure 1 shows the water absorptivity of the sample and the recycled papers. The maximum water absorptivity for the sample paper and re-pulped paper is achieved in 15 minutes, whereas for the deinked paper and bleached paper, the maximum water absorptivity is reached in 10

minutes. As shown in Fig. 1, the water absorptivity of recycled papers is higher than of sample papers. This could be because of the high porosity of the recycled paper, as they were not pressed. The present results show that recycled papers may not be suitable for writing purposes as they may absorb a large amount of solvents such as ink. Never- theless, recycled papers can be used to make tissue and blotting paper. It can also be used for other purposes like making egg crates, boxes, menus, etc.

3.3 XRD and FTIR analyses

XRD and FTIR analyses studied the structure and surface functional groups of the sample and the recycled papers. As shown in Fig. 2a, all the samples show two broad diffraction peaks centered approximately at diffraction angles of 15.6 and 22.5°, corresponding to cellulose^{21, 22）}, which is one of the most important polysaccharides in the plant cell wall and is widely used in the papermaking industry. XRD data clearly show that the sample and the recycled paper contain several filler minerals. Sharp diffraction peaks observed at diffraction angles of 9.4 and 28.6° in SP, RP, and DP correspond to talc（Mg3Si2O10）^{23, 24）}. In comparison, weak diffraction peaks at 12.4 and 25.0° indicate the presence of kaolinite（Al2Si2O（OH）5 4）^{25, 26）}. Similarly, the diffraction peak at 29.4° indicates the presence of calcite（CaCO3）^{25, 27）}. Besides, trace amounts of dolomite and silica were also detected. Due to bleaching, the intensi- ties of the diffraction peaks corresponding to minerals become low in the BP, suggesting cellulose as the main composition of the paper. From the quantitative analyses

（Reference Intensity Ratio: RIR method）, it was found that the sample paper contains 10 mass％ talc, 7 mass％ kaolin- Fig. 1　Water absorptivity of the sample and the recycled

papers.

(6)

623 ite, and 4 mass％ calcite. At the same time, the bleached

paper contains only 3 mass％ talc, and 3 mass％ calcite.

Note that mineral fillers are highly desirable in the paper industry, particularly in printing papers, to improve the printing properties. The most common mineral fillers are magnesium silicate（talc）, kaolin, precipitated silica and sili- cates, and grounded calcite^28）. The pulp is usually used as a pitch control agent, coating pigment, and functional filler.

Talc is one of the major fillers used in papermaking to improve opacity, brightness, and printing properties^{29, 30）}. Similarly, kaolin is used to improve the paper s appearance, such as gloss, smoothness, brightness, and opacity, so that the printability of the paper can be improved. Ground and precipitated calcite are generally used in papermaking to lower the paper production cost and to improve the paper s opacity and brightness. A drastic decrease of the filler minerals in the bleached paper suggests that the recycled bleached paper loses the quality with limited use for printing purposes.

FTIR spectra of the sample and the recycled papers are shown in Fig. 2b and Fig. 2c. As shown in Fig. 2b, major

absorption bands are observed in the wave-number regions of 2800−3500 cm⁻¹ and 550−1650 cm⁻¹ characteristic of cellulose samples from wood pulp containing hydroxyl, carbonyl and methyl functional groups^31）. Obvious visible differences were not noted in the FTIR spectra of the sample paper and the recycled papers suggesting that deinking and bleaching did not cause any significant changes in the chemical structure of the papers. The major sharp absorption band at 3334 cm⁻¹ corresponds to the stretching vibration of the O–H bond in cellulose characteristic for hydroxyl group in polysaccharides and infer in- ter-and intramolecular hydrogen bond vibration in cellulose^32）. The absorption band at 2897 cm⁻¹ can be attributed to hydrocarbon s C–H stretching vibration. Another intense absorption band at 1029 cm⁻¹ corresponds to the stretching vibration of the C–O bond in cellulose. The FTIR peak located approximately at 1635 cm⁻¹ shows the presence of water molecules absorbed in the papers. The minor absorption bands at 1427, 1369, 1335, 896 cm⁻¹ can be attributed to the stretching and bending vibrations of –CH2 and –CH and –OH and C–O bonds of the cellulose^33）. The absorption bands in the lower wave-number region of 500–1000 cm⁻¹ can be attributed to the vibration of Si–O and Al–OH groups^24）, which agrees with the XRD data.

3.4 Surface morphology

The surface morphology of the sample and the recycled papers were studied by SEM imaging. Figure 3 shows SEM images of the samples at different magnifications. As seen in the SEM images, all the samples exhibit fibrous structures typical of cellulose fibers. Careful observations of the low-magnification SEM images（Figs. 3a, 3d, 3g, 3j）reveal Fig. 2　（a）XRD patterns; （b）FTIR spectra of the sample

and the recycled papers; （c）the corresponding FTIR spectra in the low wavenumber region.

Fig. 3　SEM images of the sample and the recycled papers:

（a-c）SP, （d-f）RP, （g-i）DP, and（j-l）BP.

(7)

J. Oleo Sci. 71, (4) 619-626 (2022) 624

that there exist randomly distributed micron size particles around the fiber structures. These could be attributed to the clay minerals present in the sample and the recycled papers, as confirmed by the XRD. Note that the density of these microparticles is less in the bleached paper compared to the rest of the samples（Fig. 3j）. The lengths of the fiber structure are found in the range of a few tens to hundreds of microns. At the same time, the diameters of the fibers are found in the range of a few hundreds of nanometers to several microns. From the high-resolution SEM images（Figs. 3c, 3f, 3i, 3l）, it is obvious that these nanosize fibers are assembled laterally, forming bundles of micron size fibers. Such morphology is commonly observed in all the samples suggesting that the fibrous structure of the sample paper is sustained even after the recycling pro- cesses of re-pulping, deinking, and bleaching.

3.5 EDS elemental analyses

Using the SEM/EDS technique elemental analysis of the sample paper and the recycled papers was performed.

Figure 4 shows EDS elemental mapping results for SP

（Figs. 4a-4h）and BP（Figs. 4i-4p）as typical examples. The EDS elemental mapping results for RP and DP are supplied in the Supporting Information（Fig. S1）. As confirmed by XRD analysis, SEM/EDS analyses reveal the homogeneous distribution of carbon, oxygen, calcium, silicon, magnesium, aluminum, and lead throughout the fibrous nano- structures of the sample paper（Figs. 4b-4h）and recycled bleached paper（Figs. 4j-4p）. Figure 5 shows the EDS

spectra of the sample paper（Fig. 5a）and the recycled papers（Fig. 5b: RP, Fig. 5c: DP, and Fig. 5d: BP）. As seen from the EDS spectra, carbon is the main element commonly present in all the samples. Besides, oxygen, calcium, silicon, magnesium, aluminum, and lead are also present in the samples due to different clay minerals（talc: Mg3Si2O10, kaolinite: Al2Si2O（OH）5 4, and calcite: CaCO3）in the pulp of the papers.

Fig. 5　 EDS spectra of the sample and the recycled papers: （a）SP, （b）RP, （c）DP, and（d）BP. The inset panels show the respective spectrum in a narrow energy range.

Fig. 4　（a）SEM image of SP and the corresponding elemental mapping of carbon（b）, oxygen（c）, calcium（d）, silicon（e）, magnesium（f）, aluminum（g）, and lead（h）. （i）SEM image of SP and the corresponding elemental mapping of carbon

（j）, oxygen（k）, calcium（l）, silicon（m）, magnesium（n）, aluminum（o）, and lead（p）.

(8)

625 Careful observation of the EDS spectra reveals that the

elemental composition of the sample paper is different compared to the recycled papers. The amount of minerals seems to be high in the sample paper, and decreasing after the recycling process. From the EDS spectra analysis, we have estimated the composition of each paper and summarized it in Table 2. The amount of major element carbon is found in the range of 72 to 86 atom％ depending on the sample. The major elements of the filler minerals such as calcium, silicon, magnesium, and aluminum decreased drastically in the bleached paper and followed a decreasing trend of SP-RP-DP-BP. While lead is assumed to come from the ink in the sample paper, ca. 0.02 atom％ decreases in the recycled papers and is estimated to be 0.01％.

4 Conclusion

In conclusion, the used paper waste was recycled following a simple method including re-pulping, deinking, and bleaching and characterized by XRD, FTIR, SEM, and EDS elemental mapping. Different physical parameters such as grammage, bulk, moisture content, water absorption, Kappa number of the sample, and the recycled papers were determined. It was found that the recycled papers have similar physical and structural properties to the sample paper. The fibrous morphology and oxygenated surface functional groups are sustained in the recycled papers. In addition to the cellulose fibers, the recycled papers contain different clay minerals such as kaolinite, talc, and calcite present in the sample paper. The lead content of the sample paper was reduced due to recycling, demonstrating the recycled papers reusability to fabricate different products from low to higher grade papers.

Acknowledgements

This research was partially funded by JSPS KAKENHI G r a n t N u m b e r J P 2 0 H 0 0 3 9 2 , J P 2 0 H 0 0 3 1 6 , a n d JP21H04685. F.S. thanks the JSPS for the postdoctoral Fel-

lowship.

Conflicts of Interest

The authors declare no conflict of interest.

Supporting Information

This material is available free of charge via the Internet at doi: 10.5650/jos.ess21396

References

1） Kumar, V.; Manwal, M.; Gupta, S.; Patil, P. Contribution in environment and revenue generation by recycling of educational institution s waste papers. J. Critical Rev. 7, 4084-4089（2020）.

2） Kumar, V. A useful contribution in conservation of environment: A case study. Asian J. Water, Environ.

Pollut. 14, 31-36（2017）.

3） Defalque, C.M.; Marin, F.A.S.; da Silva, A.F.; Rodríguez, E.Y.A. A review of waste paper recycling networks fo- cusing on quantitative methods and sustainability. J.

Mater. Cycles Waste Manag. 23, 55-76（2021）. 4） Wichmann, B.; Luckert, M.; Bissonnette, K.; Cumber-

land, A.; Doll, C. et al. Using pro-environmental information to modify conservation behavior: paper recycling and reuse. Recycling 2, 5（2017）.

5） Shrestha, R.L.; Chaudhary, R.; Shrestha, R.G.; Shrest- ha, T.; Maji, S. et al. Washnut seed-derived ultrahigh surface area nanoporous carbons as high rate perfor- mance electrode materials for supercapacitors. Bull.

Chem. Soc. Jpn. 94, 565-572（2021）.

6） Shrestha, R.G.; Maji, S.; Shrestha, L.K.; Ariga. K. Nano- architectonics of nanoporous carbon materials in supercapacitors applications. Nanomaterials 10, 639

（2020）.

7） Zhou, S.; Xia, L.; Fu, Z.; Zhang, C.; Duan, X. et al. Pu- Table 2　Elemental composition of the sample and the recycled papers based on EDS analyses.

Element Series [norm. at.%]

SP [norm. at.%]

RP [norm. at.%]

DP [norm. at.%]

BP

Carbon K-series 72.11 79.84 86.68 81.34

Oxygen K-series 22.06 17.84 12.79 17.96

Calcium K-series 2.91 0.65 0.16 0.39

Silicon K-series 1.03 1.04 0.16 0.16

Magnesium K-series 1.37 0.39 0.08 0.08

Aluminum K-series 0.48 0.21 0.08 0.03

Lead M-series 0.02 0.01 0.01 0.01

(9)

J. Oleo Sci. 71, (4) 619-626 (2022) 626

rification of dye-contaminated ethanol-water mixture using magnetic cellulose powders derived from agri- cultural waste biomass. Carbohydr. Polym. 258, 117690（2021）.

8） Shrestha, L.K.; Thapa, M.; Shrestha, R.G. Maji, S.;

Pradhananga, R.R.; Ariga, K. Rice husk-derived high surface area nanoporous carbon materials with excel- lent iodine and methylene blue adsorption properties.

C J. Carbon Res. 5, 10（2019）.

9） Pradhananga, R.R.; Adhikari, L.; Shrestha, R.G.; Ad- hikari, M.P.; Rajbhandari, R. et al. Wool carpet dye adsorption on nanoporous carbon materials derived from agro-product. C J. Carbon Res. 3, 12（2017）.

10） Suneetha, M.; Syama Sundar, B.; Ravindhranath, K.

Extraction of fluoride from polluted water using low- cost-active carbon derived from stems of Acalypha in- dica Plant. Asian J. Water Environ. Pollut. 12, 33-49

（2015）.

11） Lei, W.; Zhou, X.; Fang, C.; Li, Y.; Song, Y.; Wang, C.;

Huang, Z. New approach to recycle office waste paper:

Reinforcement for polyurethane with nano cellulose crystals extracted from waste paper. Waste Manag.

95, 59-69（2019）.

12） M hamdi, A.I.; Kandri, N.I.; Zerouale, A.; Blumberga, D.;

Gusca, J. Life cycle assessment of paper production from treated wood. Energy Procedia 128, 461-468

（2017）.

13） Liang, S.; Zhang, T.; Xu, Y. Comparisons of four catego- ries of waste recycling in China s paper industry based on physical input-output life-cycle assessment. Waste Manag. 32, 603-612（2012）.

14） Bahrami, B.; Jafari, P. Paper recycling, directions to sustainable landscape. Int. J. Environ. Sci. Technol.

17, 371-382（2020）.

15） ISO 536. International standard, 3rd Edition, Switzer- land（2012）.

16） ISO 302: International standard, 3rd Edition, Switzer- land（2015）.

17） Bloch, J.-F.; Engin, M.; Sampson, W.W. Grammage de- pendence of paper thickness. Appita J. 71, 30（2019）. 18） Vieira, J.C.; Mendes, A. de O.; Carta, A.M.; Fiadeiro,

P.T.; Costa, A.P. Experimental dataset supporting the physical and mechanical characterization of industrial base tissue papers. Data in Brief 33, 106434（2020）. 19） Alava, M.; Niskanen, K. The physics of paper. Rep.

Prog. Phys. 69, 669-723（2006）.

20） Shen, W.; Chen, X. Measuring and controlling model of pulp Kappa number with spectroscopy during batch sulfite pulping process. Ind. Eng. Chem. Res. 48, 8980-8984（2009）.

21） Ju, X.; Bowden, M.; Brown, E.E.; Zhang, Z. An improved X-ray diffraction method for cellulose crystal-

linity measurement. Carbohydr. Polym. 123, 476-481

（2015）.

22） Aminah, B.; Kose, R. Properties of cellulose nanofibers prepared from recycled pulp fiber using the aqueous counter collision method. J. Fiber Sci. Technol. 75, 140-144（2019）.

23） Kursun, H.; Ulusoy, U. Influence of shape characteris- tics of talc mineral on the column flotation behavior.

Int. J. Miner. Process. 78, 262-268（2006）.

24） Marzbani, P.; Resalati, H.; Ghasemian, A.; Shakeri, A.

Surface modification of talc particles with phthalimide:

Study of composite structure and consequences on physical, mechanical, and optical properties of deinked pulp. BioResources 11, 8720-8738（2016）.

25） Kłosek-Wawrzyn, E.; Małolepszy, J.; Murzyn, P. Sinter- ing behavior of Kaolin with calcite. Procedia Eng. 57, 572-582（2013）.

26） Biel, O.; Rożek, P.; Florek, P.; Mozgawa, W.; Król, M.

Alkaline activation of Kaolin group minerals. Crystals 10, 268（2020）.

27） Pesenti, H.; Leoni, M.; Scardi, P. XRD line profile analysis of calcite powders produced by high energy mill- ing. Z. Kristallogr. Suppl. 27, 143-150（2008）.

28） Bundy, W.M.; Ishley, J.N. Kaolin in paper filling and coatings. Appl. Clay Sci. 5, 397-420（1991）.

29） Chauhan, V.S.; Bhardwaj, N.K. Efficacy of dispersion of magnesium silicate（talc）in papermaking. Arabian J. Chem. 10, S1059-S1066（2017）.

30） Han, J.S.; Jung, S.Y.; Kang, D.S.; Seo, Y.B. Develop- ment of flexible calcium carbonate for papermaking filler. ACS Sustain. Chem. Eng. 8, 8994-9001（2020）. 31） Hospodarova, V.; Singovszka, E.; Stevulova, N. Charac- terization of cellulosic fibers by FTIR spectroscopy for their further implementation to building materials.

Am. J. Anal. Chem. 9, 303-310（2018）.

32） Rosa, M.F.; Medeiros, E.S.; Malmonge, J.A.; Gregorski, K.S.; Wood, D.F. et al. Cellulose nanowhiskers from coconut husk fibers: Effect of preparation conditions on their thermal and morphological behavior. Carbo- hydr. Polym. 81, 83-92（2010）.

33） Xu, F.; Yu, J.; Tesso, T.; Dowell, F.; Wang, D. Qualitative and quantitative analysis of lignocellulosic biomass using infrared techniques: A mini-review. Appl. Energy 104, 801-809（2013）.

CC BY 4.0（Attribution 4.0 International）. This license allows users to share and adapt an article, even commercially, as long as appropriate credit is given. That is, this license lets others copy, distrib- ute, remix, and build upon the Article, even commercially, provided the original source and Authors are credited.

View publication stats