© 2017 The Authors. Published by Center for Pulp and Paper, Ministry of Industry, Indonesia
94
MATERIALS AND METHOD Materials
Oil palm (elaeis guneensis) frond samples were obtained from Palm Oil Mill Plant PT Fajar Baizury and Brothers, Aceh, Indonesia. It were cut into chips at an approximate length 2 inches and were subsequently dried before pulped. Old Newsprints (ONP) and OCC has been used with approximately 1.0 cm x 1.0 cm in dimension and soaked for 24 hours in water. Comminution of raw materials was not employed with scissors to avoid fibers cut off occurs during comminution.
Pulping
The OPF chips (200 g, o.d. basis) were pulped using an acetosolv in 4 L stationary stainless steel digester (NAC Autoclave Co. Ltd., Japan) employed with a computer-controlled thermocouple.
Different acetosolv pulping conditions were run based on experimental design via a statistical modeling software (Design Expert). After optimization, the OPF was pulped at the best possible acetosolv pulping conditions, which were; 85% of acetic acid, 0.75% of HCl, 155oC of cooking temperature and 140 minutes for cooking time. Both the acetic acid and HCl concentration were based on volume percentage (v/v) with respect to the cooking liquor. The OPF pulp produced was used as virgin pulp for this study.
Paper Making
The papermaking process was carried using semi automatic handsheet papermaking. The mixing ratio of OPF acetosolv pulp to secondary pulp is listed in Table 1. Then , the handsheets were placed in air conditioned room (50.0 ± 2.0% RH and 23.0 ± 1.0oC) ( (TAPPI Test Methods 1994).
Table 1 Mixing Ratio of Pulp
Sample Pulp Acetosolv OPF Secondary Pulp ( OCC or ONP)
A 0 100
B 20 80
C 40 60
D 60 40
F 80 20
F 100 0
RESULTS AND DISCUSSION
Effect of Material Mixing Ratio on Density
Refer to Fig.1 shows that the density of the paper increased for both types of secondary fibers with the addition of OPF. The increase could be presumed as the result of interchange of stiffer secondary fiber with virgin OPF fibers which more flexible which produced a higher dense and shorter fibers, it can be seen an increase in its density. Moreover, the effect of the addition of OPF fiber is greater than the secondary fiber pulp ONP versus OCC. ONP is usually made of fibers with bleaching treatment while OCC is made from pulps without bleaching. The bleaching process could affected the fibers more flexible (McDononough, 1977). Thus, the density is higher as shown in Fig.1 in this discussion.
Effect of Mixing Ratio on Tensile Index
Fig. 2 shows the effect of OPF fiber mixing ratio with secondary fibers from OCC and ONP has a very good results due to the increased of tensile index of OCC drastically only with the addition of 20% OPF fiber. Small increase of ONP tensile presumably due to the high quality of secondary fiber source applied. This result indicated that the acetosolv OPF pulp is very influential to be used as a
95 reinforcing material primarily for OCC fibers. This fact might be occurred due to fibers exchanging between inactive secondary fibers with OPF active fibers. Active herein refers to fibers which have more potential to form bonds between fibers (hydrogen bonding). Many researchers also had studied about the activity of this virgin fibers (Billosta et al., 2006; Andreasson et al., 2003; and Tze &
Gardner, 2001).
Fig. 1. Effect of Pulp Mixing Ratio on Density
Fig. 2. Effect of Mixing Pulp Ratio on Tensile Index Effect of Mixing Ratio on Burst Index
Fig. 3 shows the mixing ratio treatment affected on reducing burst index of secondary fibers with the addition of OPF fiber. Burst index is dependent on the fiber length, its strength, and amount of bonding between the fibers. The first two factors are the most influential on burst index. Though OPF fiber is virgin fiber that is able to increase the fibers bonding but less competitive compare with the role of both factors; fiber length and fiber strength. In acetosolv cooking of OPF, fiber length and fiber strength has been reduced as a result of fibers degradation during cooking at temperatures exceeding 140oC (Wanrosli, et al., 2011).
0.40 0.45 0.50 0.55 0.60 0.65
100/0 80/20 60/40 40/60 20/80 0/100 Density (g/cm3)
Ratio, % (Secondary pulp : OPF asetosolv pulp) OCC ONP
25 30 35 40 45 50
100/0 80/20 60/40 40/60 20/80 0/100
Tensile Index (N.m/g)
Ratio, % ( Secondary pulp : Pulp OPF asetosolv) OC
C
96
Fig. 3. Effect of Pulp Mixing Ratio on Burst Index.
Effect of Pulp Mixing Ratio on Brightness
Degree of brightness can be interpreted as a reflection of a set of thick paper at a wavelength of 457 nm (Borch, 2002). Based on Fig. 5 it may be noted that the effect of increasing mixing ratio of OPF pulp fibers to secondary pulp fibers, the ONP degree of brightness is decrease, while for OCC is slightly increase. It has been predicted for ONP secondary fiber is brightly colored, while OCC is slightly dark, compared to OPF pulp fibers. According to Kubelka-Munk equation, the degree of brightness is largely dependent on the absorption coefficient K besides scattering coefficient S. K coefficient is strongly influenced by color, thus, the addition of OPF pulp fiber will reduce the degree of ONP brightness, otherwise increase of the degree of brightness of OCC pulp fibers due to its nature of the OCC is darker than that of OPF pulp fibers.
Fig. 4. Effect of Pulp Mixing Ratio on Brigness.
5.00 5.20 5.40 5.60 5.80 6.00 6.20 6.40 6.60 6.80 7.00
100/0 80/20 60/40 40/60 20/80 0/100 Burst Index (mNm2/g)
Ratio, % (Secondary pulp : Pulp OPF asetosolv) OCC
ONP
10 15 20 25 30 35 40 45 50 55 60
100/0 80/20 60/40 40/60 20/80 0/100
Brigness (%)
Ratio , % (Secondary Pulp : Pulp OPF asetosolv ) OCC ONP
97 Effect of Pulp Mixing Ratio on Opacity
Fig. 5 shows effect of mixing ratio on opacity. The effect of increasing mixing ratio of OPF pulp fibers to secondary pulp fibers, the ONP opacity is increase, while for OCC is slightly decrease. This result can be described by Kubelka Munk equation which opacity also is dependent on the scattering coefficient S and absorption coefficient K. In this case, if OPF pulp fiber is added (high K) then the opacity will increase for ONP secondary pulp fibers. Conversely to the secondary OCC pulp fibers which are basically dark color, then the addition of the OPF pulp fiber will decreasing K OCC higher than that of secondary K.
Fig. 5. Effect of Pulp Mixing Ratio on Opacity
CONCLUSIONS
Based on the results of research that has been done can be concluded as follows:
1. Density of the paper increased for both types of secondary fibers with the addition of OPF pulp fiber.
2. OPF fiber mixing ratio with secondary fibers from OCC and ONP has a very good results due to the increased of tensile index of OCC drastically only with the addition of 20% OPF fiber.
Small increase of ONP tensile presumably due to the high quality of secondary fiber source applied.
3. The mixing ratio treatment affected on reducing burst index of secondary fibers with the addition of OPF fiber.
4. The effect of increasing mixing ratio of OPF pulp fibers to secondary pulp fibers, the ONP degree of brightness is decrease, while for OCC is slightly increase.
5. The effect of increasing mixing ratio of OPF pulp fibers to secondary pulp fibers, the ONP opacity is increase, while for OCC is slightly decrease.
6. OPF pulp fiber mixing ratio with secondary fiber ONP and OCC has shown that the OPF fiber can improve the strength of the secondary paper (tensile) to 26% for OCC and ONP to 20%. It is an advantage for secondary fiber based paper industry which it factories using chemicals to improve paper strength. Otherwise it will change the physical, mechanical and optical properties of its paper products.
if the added fiber OPF had done eating refining the addition is much lower which can result in savings of operating funds making paper from pulp fiber secondary.
94 95 96 97 98 99 100 101
100/0 80/20 60/40 40/60 20/80 0/100
Opacity (%)
Ratio, % (Secondary Fiber: OPF asetosolv Pulp) OCC ONP
98
ACKNOWLEDGMENTS
The author would to thank to Universiti Sains Malaysia for providing its laboratory facilities during this research and PT.Fajar Baizury Brothers, Aceh, Indonesia, for providing Oil Palm Fronds from their plantations
REFERENCES
_______________., 2007, “ Indonesia Pulp and Paper Industry Directory”, Indonesia Pulp and Paper Association, Printed by Gramedia.
Allison, R. (1992). Bleaching Alkaline Pulp from Pinus Radiata, N.Z.J. Forestry Sci.21 (1) 107-114.
Billosta, V., Brandstroom , J., Coachaux, A., Joseau, J-P., & Ruel, K. (2006). Utrastructura Organizion of the Wood Cell Wall can Explain Mondifions Cauded in Fibers During the Pupling Process. Celluse Chem. Technol., 40.223-229.
Borch, J. (2002). Otical and Appearance Properties, in Handbook of Physica Testing of Paper, 2 Ed., J. Borch, M.B.Lyne.R.E. Max, and C.C. Haberger, jr. (eds). Vol.1.
Erwinsyah. Susi Sugesty dan Taufan Hidayah., 2011. “ Pembuatan pulp mekanis tanda kosong Sawit untuk kertas Lainer dan Medium” Prosiding Seminar Teknologi Pulp dan Kertas, Balai Besar Pulp dan kertas 2011.
TAPPI. (1994). Test Methods 1994-1995. Tappi Press. Atlanta USA
McDonough, T.J. (1997). Simultaneous Brightening and Strengthening of Groundwood.
Thermomechmenical Pulp and High Yield Bisulfite. Pulp Paper Can.78,63-68.
Page. D.H. (1994) Note on The Mechanism of Tearing Strength. Tappi J. 77 (3), 201-203.
Tze, W.T. & D.J. Gardner. (2001). Swelling of Recycled Wood Pulp Fiber Science 33 (3) 364-376.
Wan Rosli, W.D., Zainuddin.Z.. & Roslan,S ( 2005). Upgrading of Recycled Paper Using Palm Fiber Soda Pulp Industrial Crops and Productsa, 21, 325-329.
WanRosli, W.D., Mazlan, I., Law, K.N, & R. Nasrullah (2011). Influnces of Opening Variables of Acetosolv Pulping on Pulp Properties from Oil Palm Fronds Maderas Ciencia tecnologia 13, 193-202.
© 2017 The Authors. Published by Center for Pulp and Paper, Ministry of Industry, Indonesia