Soda pulping of Miscanthus sinensis. Effects of operational variables on pulp yield and lignin solubilization

1996 ◽  
Vol 58 (1) ◽  
pp. 17-23 ◽  
Author(s):  
G Iglesias ◽  
M Bao ◽  
J Lamas ◽  
A Vega
2018 ◽  
Vol 53 (1) ◽  
pp. 1-6 ◽  
Author(s):  
S Sutradhar ◽  
M Sarkar ◽  
J Nayeem ◽  
M Sarwar Jahan ◽  
C Tian

Four non-woods such as, dhaincha (Sesbania bispinosa), jute stick (Corchorus capsularis), wheat straw (Triticum aestivum) and corn stalks (Zea mays) were cooked by potassium hydroxide (KOH) at the optimum conditions of soda pulping. Dhaincha, wheat straw and corn stalks were delignified to kappa number 19.4, 13.6 and 19, respectively, while jute stick was not delignified sufficiently (kappa number 32.5). All these four raw materials maintained good yield in KOH process. Dhaincha produced the highest pulp yield (50.5%) and wheat straw had the lowest pulp yield (44.7). All pulps were bleached by D0EpD1 bleaching sequences in identical bleaching conditions. Final pulp brightness reached to above 80% ISO except jute stick pulp. Jute stick pulp reached to 74.9% brightness only after the consumption of 30 kg ClO2/ ton of pulp. The overall bleaching yields were 92.6%, 88.4%, 90.1 and 90.8% for dhaincha, jute stick, wheat straw and corn stalks pulps, respectively. The oSR of these four non-wood bleached pulps was above 20, consequently improved papermaking in the unrefined state. Beating rapidly increased papermaking properties, as for example, the tensile index of dhaincha pulps increased from 49 N.m/g in the unrefined pulp to 90 N.m/g in the beaten 50 oSR. It can be seen that KOH is a good substitute to soda process for non-wood.Bangladesh J. Sci. Ind. Res.53(1), 1-6, 2018


2008 ◽  
Vol 5 (1) ◽  
pp. 81-85 ◽  
Author(s):  
A. U. Israel ◽  
I. B. Obot ◽  
S. A. Umoren ◽  
V. Mkpenie ◽  
J. E. Asuquo

Cellulosic polymers namely cellulose, di-and triacetate were produced from fourteen agricultural wastes; Branch and fiber after oil extraction from oil palm(Elais guineensis), raffia, piassava, bamboo pulp, bamboo bark from raphia palm(Raphia hookeri), stem and cob of maize plant(Zea mays), fruit fiber from coconut fruit(Cocos nucifera), sawdusts from cotton tree(Cossypium hirsutum), pear wood(Manilkara obovata), stem of Southern gamba green (Andropogon tectorus), sugarcane baggase(Saccharium officinarum)and plantain stem (Musa paradisiaca). They were subjected to soda pulping and hypochlorite bleaching system. Results obtained show that pulp yield from these materials were: 70.00, 39.59, 55.40, 86.00, 84.60, 80.00, 40.84, 81.67, 35.70, 69.11, 4.54, 47.19, 31.70 and 52.44% respectively. The pulps were acetylated with acetic anhydride in ethanoic acid catalyzed by conc. H2SO4 to obtain cellulose derivatives (Cellulose diacetate and triacetate). The cellulose diacetate yields were 41.20, 17.85, 23.13, 20.80, 20.23, 20.00, 39.00, 44.00, 18.80, 20.75, 20.03, 41.20, 44.00, and 39.00% respectively while the results obtained as average of four determinations for cellulose triacetate yields were: 52.00, 51.00, 43.10, 46.60, 49.00, 35.00, 40.60, 54.00, 57.50, 62.52, 35.70. 52.00, 53.00 and 38.70% respectively for all the agricultural wastes utilized. The presence of these cellulose derivatives was confirmed by a solubility test in acetone and chloroform.


BioResources ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 103-120
Author(s):  
Harjeet Kaur ◽  
Dharm Dutt ◽  
C. H. Tyagi

Sofia (Cymbopogon martini), and lemon (Cymbopogon flexuosus) grasses, are exclusively cultivated for extraction of important lemongrass and palma rosa oils. Lignocellulosic residue (LCR) of sofia and lemon grasses left after steam distillation can successfully be used for the production of chemical grade pulp. Steam distillation mitigates the problem of mass transfer, and facilitates the faster penetration of cooking liquor by leaching out a part of extraneous components. Sofia grass produces a pulp yield of 43.7% of kappa number 20 at an active alkali dose of 14% (as Na2O), maximum cooking temperature of 160 oC and cooking time 90 min. Likewise, lemon grass produces a pulp yield of 41.4% of kappa number 12.5 under the same conditions except temperature (150 oC) by a soda pulping process. Addition of 0.1% AQ at optimum cooking conditions reduces kappa number by 26 and 8% for sofia and lemon grasses with insignificant increase in pulp yield i.e. 0.2 and 0.4% for sofia and lemon grasses, respectively. The mechanical strength properties of lemon grass soda-AQ pulp are better than sofia grass. Bauer-McNett fiber classification further validates that +20 fractions are more (62.63%) in lemon grass than in sofia grass (42.72%).


Holzforschung ◽  
2000 ◽  
Vol 54 (5) ◽  
pp. 544-552 ◽  
Author(s):  
S. Abad ◽  
V. Santos ◽  
J. C. Parajó

Summary Populus tremula* Populus tremuloides wood samples were subjected to three-stage pulping in formic acid media with hydrogen peroxide addition, according to the Milox process. By means of three incomplete, second-order, centered, factorial designs, the effects of selected operational variables on the composition and technical properties of pulps were assessed for optimization purposes. Under the best conditions assayed, a pulp with 2.30% lignin, 87.0 % cellulose and 3.25% xylan was obtained at 53.2% pulp yield. Good SCAN viscosity (826 ml/g), reduced Kappa number (9.0) and satisfactory alkaline resistance (R-10 = 89.0; R-18 = 91.0) proved the potentiality of the selected pulp for dissolving pulp production.


2021 ◽  
Vol 12 (1) ◽  
pp. 230-242
Author(s):  
Henry Okwudili Chibudike ◽  
Nelly Acha Ndukwe ◽  
Eunice Chinedum Chibudike ◽  
Nkemdilim Ifeanyi Obi ◽  
Olubamike Adetutu Adeyoju

Pulping trials were carried out using MEA and the soda process comparing their pulping potentials. The operating conditions such as the concentration of the cooking liquor (50%, 75%, 100%) for MEA and (10%, 15%, 20%) for NaOH, the maximum cooking temperature (150oC, 160oC, 170oC) and cooking time (60, 90, 120minutes) for both processes were investigated systematically to establish optimal pulping conditions. The agro-biomass used in this investigation is Sugarcane Bagasse viewed as alternative raw material for pulp and paper production. The lignin content of Bagasse (19.5%) was low; indicating that Bagasse should be easier to pulp. The optimum cooking conditions (independent variables) for MEA pulping were 75% MEA concentration, 150oC cooking temperature and 90 minutes cooking time. Excel 2013 was used to analyze the effect of independent variables on yield of bagasse pulp and properties of furnished paper from MEA process in comparison with the Soda process which include tear index, tensile index, burst index and folding endurance with errors less than 15% in all cases. The Kappa number range (12.7-16.9), viscosity (270-870 ml/g) and brightness (62.1-93.2%) of bagasse pulp are appropriate for high-brightness printing and writing papers. The physical properties of furnished paper, tear index (13.4 mN.m2/g), tensile index (71Nm/g), Burst index (4.8 KN/g) and folding endurance (82) recommend the cellulosic pulp from Sugarcane Bagasse obtained from the MEA process for strengthening the virgin fiber in recycled papers and also for developing certain types of printing and packaging papers. Due to the awareness towards the negative impact of kraft mill’s effluent to the environment recently, soda pulping started to regain its popularity among the pulp mills especially non-wood based pulp mills. MEA process is more economically attractive given its high pulp yield, despite the significant increase in chemical demand for bleaching. MEA pulping is a good alternative to soda pulping furnishing high pulp yield with less cooking temperature, i.e. 150oC, thereby saving a considerable amount of energy with less odoriferous pollutants and pollution load associated with the soda process.


2017 ◽  
Vol 37 (1) ◽  
pp. 1-8
Author(s):  
B. O. Ogunsile ◽  
M. A. Omotoso

Organosolv pulping processes have been developed as a substitute to the conventional process because of its little or no emission into the environment. Plantain stalk was subjected to acetosolv pulping at atmospheric conditions under the influence of three operating parameters, namely, concentration of acetic acid, H2SO4 – catalyst and time. The influence of the operationalvariables on the pulp yield was evaluated using a second - order factorial design. The results showed that the highest pulp yield was 64.14 % which was obtained at the lowest value of the operational variables. The greatest influence on the pulp yield was caused by the concentration of acetic acid while the H2SO4 – catalyst had the least. The polynomial equation derived predicted the pulp yields with errors less than 6 %.Keywords: Acetosolv, pulp yield, operational variables, factorial design


2020 ◽  
Vol 3 (2) ◽  
pp. 170
Author(s):  
Maria Ulfa ◽  
Koriatul Isnaini

Abstract The potential use of coir fiber for pulping and papermaking has been investigated. This research aimed to study effects of pulping processing variables (temperature, pulping time, and alkali charge/solvent pulping) on the properties of pulp (residual lignin, alpha cellulose, kappa number and pulp yield) from coir fiber. For this purpose, the coir fibers were cooked using alkali charge (10 to 20% oven dried, as NaOH), pulping time from 60 to 120 min and temperature from 65 to 180oC. Results indicated that alkali charge and pulping time gave more impact on the properties of pulp than temperature. Pulping at high temperature, long pulping time, and high alkali charge resulted in decreasing of lignin, pulp yield, and kappa number but instead on alpha cellulose content. Keywords: coir, soda pulping, lignin


2016 ◽  
Vol 22 (5) ◽  
pp. 1084-1097 ◽  
Author(s):  
Hilda M. Hernández-Hernández ◽  
Jorge J. Chanona-Pérez ◽  
Alberto Vega ◽  
Pablo Ligero ◽  
Reynold R. Farrera-Rebollo ◽  
...  

AbstractThe peroxyformic process is based on the action of a carboxylic acid (mainly formic acid) and the corresponding peroxyacid. The influences of processing time (60–180 min), formic acid concentration (80–95%), temperature (60–80°C), and hydrogen peroxide concentration (2–4%) on peroxyformic pulping of agave leaves were studied by surface response methodology using a face-centered factorial design. Empirical models were obtained for the prediction of yield,κnumber (KN) and pulp viscosity as functions of the aforementioned variables. Mathematical optimization enabled us to select a set of operational variables that produced the best fractionation of the material with the following results: pulp yield (26.9%), KN (3.6), and pulp viscosity (777 mL/g). Furthermore, this work allowed the description and evaluation of changes to the agave fibers during the fractionation process using different microscopic and spectroscopic techniques, and provided a comprehensive and qualitative view of the phenomena occurring in the delignification of agave fibers. The use of confocal and scanning electron microscopy provided a detailed understanding of the microstructural changes to the lignin and cellulose in the fibers throughout the process, whereas Raman spectroscopy and X-ray diffraction analysis indicated that cellulose in the pulp after treatment was mainly of type I.


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