scholarly journals Comparative Studies of Pulping of Jute Fiber, Jute Cutting and Jute Caddis

1970 ◽  
Vol 42 (4) ◽  
pp. 425-434 ◽  
Author(s):  
M Sarwar Jahan ◽  
A Al-Maruf ◽  
MA Quaiyyum
Keyword(s):  
Comparative Studies ◽  
Raw Materials ◽  
Lignin Content ◽  
Kappa Number ◽  
Dissolving Pulp ◽  
Jute Fiber ◽  
Pulp Yield ◽  
Pulp Fiber ◽  
Cellulose Content ◽  
Kraft Process

Comparative studies of retted jute fiber, jute cuttings and jute caddis were carried out in producing dissolving and paper grade pulp. Fiber length of jute fiber was longer than jute cutting and caddis. Klason lignin content was lower and α-cellulose content higher in jute fiber than cuttings and caddis. Extractives content in caddis was higher than jute fiber and cuttings. Pulping of these raw materials was done in soda-anthraquinone process. Higher pulp yield and lower kappa number was observed in jute fiber than that of jute cuttings and caddis. Jute fiber pulp showed better papermaking properties than jute cuttings and caddis. The tear index of these raw materials was similar to softwood. The bleachability of jute fiber pulp was also better than that of cuttings and caddis. These three raw materials were also evaluated in producing dissolving pulp by prehydrolysed kraft process. Pulp yield and bleachability was higher and kappa number lower for jute fiber than jute cuttings and caddis, but α-cellulose, S10 and S18 values and viscosity were almost similar in these three raw materials. Keywords: Jute fiber, Jute cuttings, Jute caddis, Paper grade pulp, Dissolving pulp Bangladesh J. Sci. Ind. Res. 42(4), 425-434, 2007

scholarly journals Ethylenediamine in alkaline cooking of jute stick for producing dissolving pulp

2015 ◽  
Vol 50 (1) ◽  
pp. 7-14
Author(s):  
M Sarwar Jahan ◽  
Halima Rahman ◽  
Purabi Rani Samaddar ◽  
Mostafizur Rahman
Keyword(s):  
Kappa Number ◽  
Dissolving Pulp ◽  
Pulp Yield ◽  
Cellulose Content ◽  
The Sacrifice ◽  
Cooking Liquor ◽  
Ecf Bleaching

Jute stick is the woody portion of jute plant. It remains as the leftover after extracting the fibre. The ratio of the stick to fibre is about 2.5:1. For producing dissolving pulp, prehydrolysis is carried out prior to pulping to remove hemicelluloses from the lignocelluloses. In this investigation ethylenediamine (EDA) was used with the cooking liquor to remove hemicelluloses from the jute stick. Increasing EDA charge in soda and kraft liquor decreased pentosans content in the pulp. EDA in kraft liquor showed lower kappa number and pentosans content than in the soda-liquor. Prehydrolysis further improved cellulose content and kappa number of jute stick pulp with the sacrifice of pulp yield. The bleachability of soda-EDA pulp was inferoior to the kraft-EDA and prehydrolysed soda-EDA in ECF bleaching sequences. The final brightness of soda-EDA pulp was 85.1% and kraft-EDA pulp 89.7%. Degraded cellulose (R18-R10) in soda-EDA and kraft-EDA pulps was lower than prehydrolysed pulps. Dissolving pulp can be produced to 93% purity without prehydrolysis by reinforcing EDA in kraft liquor.Bangladesh J. Sci. Ind. Res. 50(1), 7-14, 2015

scholarly journals Potassium hydroxide pulping of four non-woods

2018 ◽  
Vol 53 (1) ◽  
pp. 1-6 ◽  
Author(s):  
S Sutradhar ◽  
M Sarkar ◽  
J Nayeem ◽  
M Sarwar Jahan ◽  
C Tian
Keyword(s):  
Wheat Straw ◽  
Potassium Hydroxide ◽  
Raw Materials ◽  
Kappa Number ◽  
Pulp Yield ◽  
Optimum Conditions ◽  
Corchorus Capsularis ◽  
Sesbania Bispinosa ◽  
Soda Pulping ◽  
Good Substitute

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

scholarly journals Comparative transcriptome analysis of Pteroceltis tatarinowii Maxim., an endemic fiber tree

2019 ◽  
Vol 48 (3) ◽  
pp. 547-557
Author(s):  
Hui-Jin Liu ◽  
Li Zhang ◽  
Yan-Nian Xu ◽  
Xiao-Ping Zhang ◽  
Xiao-Hong Li
Keyword(s):  
Protein Gene ◽  
Raw Materials ◽  
Lignin Content ◽  
Hierarchical Cluster ◽  
Raw Material ◽  
Limiting Factor ◽  
Cellulose Content ◽  
Three Samples ◽  
Phenylpropanoid Biosynthesis ◽  
Significant Expression

The bark of Pteroceltis tatarinowii Maxim., an endemic tree in Ulmaceae, is the main raw material for manufacturing Xuan Paper which is widely used in calligraphy and painting field. The characteristics of P. tatarinowii bark is the main limiting factor for the quality of Xuan Paper specially the content of cellulose and lignin. The molecular basis related to cellulose and lignin synthesis in P. tatarinowii would be helpful to understand and seek higher quality raw materials for Xuan Paper. RNA-seq was utilized to reveal transcriptome differences in P. tatarinowii from three far isolated localities (AL, JX and XA) under different climate environments. A total of 290 million reads were generated for further analysis in three libraries. In total, 2,850, 2,038 and 1,986 DEGs were identified in XA, JX and AL, respectively. Compared with the sample from XA, there were 822 up-regulated and 1706 down-regulated in AL sample. AL sample has 611 up-regulated genes and 647 down-regulated genes in comparison with JX sample. Comparing XA and JX samples, 443 were up-regulated and 1,783 were down-regulated in XA. Three samples had similar GO enrichment patterns. There were 19 and 9 genes identified as CESA and CSL (E-value less than 1.0E-20), respectively. Although no significant expression differences were found in three samples, KOB1, GPI-anchored protein gene and CTL1 were differently expressed, and KOB1 and GPI-anchored protein gene were up-regulated in JX. A number of the unigenes (474) that were involved in ‘phenylpropanoid biosynthesis’, were mostly not differently expressed. Only a few genes annotated as PAL, 4CL, C4H and CAD were significantly different in expression. In AL, 3 CAD and 1 PAL were up-regulated, whereas 6 CAD, 3 4CL and 1 HCT were up-regulated in XA, and 1 PAL, 2 4CL, 2 C4H in JX. JX sample had the highest cellulose content and XA sample had the highest lignin content, which being consistent with the hierarchical cluster analysis of differently expressed genes. Differences in the expression of these genes might influence the cellulose and lignin content.

Dissolving pulp from white press cuttings

TAPPI Journal ◽  
2016 ◽  
Vol 15 (4) ◽  
pp. 277-282 ◽  
Author(s):  
M. SARWAR JAHAN ◽  
RAJESH CHANDRA DEB ◽  
M. MOSTAFIZUR RAHAMAN ◽  
M.A. QUAIYYUM
Keyword(s):  
Acid Treatment ◽  
Ash Content ◽  
Dissolving Pulp ◽  
Pulp Yield ◽  
Cellulose Content ◽  
Alkaline Extraction ◽  
Rayon Production ◽  
Oligomeric Form ◽  
White Press ◽  
Pentose Sugars

Upgrading of white press cuttings into dissolving pulp was carried out by acidification followed by alkaline extraction. Acid treatment decreased ash content of white press cutting pulp from 11.25% to 0.33% at pH 2. The yield after acidification and screening was 87%. Alkaline extraction removed hemicelluloses and increased α-cellulose content to 92% with viscosity value of 4.3 mPa.s. The overall pulp yield after alkaline extraction was 76.6%. Alkaline extracted liquor contains 9.2% total organics, mostly pentose sugars in the oligomeric form. The produced dissolving pulp can be used for rayon production.

Target Kappa Number for AS/AQ Pulping of Wheat Straw

2011 ◽  
Vol 236-238 ◽  
pp. 1431-1436
Author(s):  
Jing Liu ◽  
Katsuya Nagata
Keyword(s):  
Mass Transfer ◽  
Wheat Straw ◽  
Transition Point ◽  
Phase Transfer ◽  
Raw Materials ◽  
Kraft Pulping ◽  
Kappa Number ◽  
Experimental Results ◽  
Raw Material ◽  
Pulp Yield

Alkaline sulfite/anthraquinone (AS/AQ) pulping of wheat straw under different conditions was conducted in this study. A transition point of kappa number at approximately 6.5 was observed based on all experimental results. This transition point can be regarded as the phase transfer point in AS/AQ pulping from bulk to residual delignification. Effective delignification without great lost of pulp yield can be achieved before kappa number was below this transition point during AS/AQ pulping of wheat straw. It is found that the ratio of cooking liquid to solid should not be lower than 6, if good mass transfer of chemicals and lignin dissolving is needed. As the ratio of Na2SO3 to NaOH dosage ranged from 0.4 to 2.4, low proportion of Na2SO3 allows effective delignification while no serious degradation of carbohydrate. Moreover, similar to kraft pulping, addition of AQ in the range of 0.05% to 0.25% is useful to remove lignin and protect the carbohydrate during AS/AQ pulping. Finally, although the transition point of kappa number may be changed while different raw material used for same pulping process or different pulping process for same raw materials, it is of interest and important for mill practice.

Temperature and effective alkali effect on brown pulp kraft cooking

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jaqueline Silveira Comelato Favaro ◽  
Gustavo Ventorim ◽  
Iliane Rodrigues de Oliveira ◽  
Cláudia Rodrigues de Oliveira
Keyword(s):  
Lignin Content ◽  
Removal Rate ◽  
Linear Trend ◽  
Total Yield ◽  
Eucalyptus Grandis ◽  
Kappa Number ◽  
Factor H ◽  
Pulp Yield ◽  
Lignin Removal ◽  
Kraft Cooking

Abstract One way to obtain high quality pulp production is to improve selectivity delignification of step, maximize yield. Brown pulp yield and chemical composition were studied, with variation of temperature and effective alkali in Kraft cooking. Considering that these variables directly affect lignin removal rate and final product quality. Industrial wood chips from Eucalyptus grandis x Eucalyptus urophylla hybrids were used in this study. The cooking was performed to obtain pulps with kappa number 13, 15 and 17 for temperatures 155 °C, 160 °C and 165 °C, using the same Factor H (695). Yields were analyzed according to: total yield, rejects content and screened pulp yield. Klason lignin content, wood and pulp sugars, levels of hexenuronic acids in pulp were also determined. Results indicate that lower cooking temperatures are beneficial in relation to cooking performance, selectivity and preservation of xylans. With a screened pulp yield of 57.1 % for KN 17 at the lowest temperature 155 ºC and 55.3 % at the same KN at 165 ºC. The lowest screened pulp yield obtained, 51 %, was for KN 13 at 165 ºC, with 54.1 % with the same KN at 155 ºC. Evidencing a decreasing linear trend of screened pulp yield with temperature increase and kappa number reduction.

scholarly journals PEMBUATAN NITROSELULOSA DARI BERBAGAI PULP LARUT KOMERSIAL SEBAGAI BAHAN BAKU PROPELAN

2014 ◽  
Vol 4 (02) ◽  
Author(s):  
Frederikus Tunjung Seta ◽  
Susi Sugesty ◽  
Teddy Kardiansyah
Keyword(s):  
Nitrogen Content ◽  
Functional Groups ◽  
Ball Mill ◽  
Dissolving Pulp ◽  
Nitrogen Level ◽  
Cellulose Content ◽  
Formula One ◽  
Kraft Process ◽  
Dissolving Pulps

One effort to overcome the limited cotton is the use of dissolving pulp or rayon pulp with high α-cellulose content. The aim of this research is to study the nitration process of cellulose from various commercial dissolved pulp into nitrocellulose, which is a material for Propellant Nitro Cellulose (PNC). The most important parameter in the preparation of propellant is nitrogen level, which should be higher than 12,75%. The dissolving pulps from softwood sulfite process (A), hardwood kraft process (B), and hardwood sulfite process (C) were pre-treated before nitration process, namely ball mill, willey mill, and blender. Nitrocellulose was made using two types of formulas, which were formula one (HNO3:HNO3 Fumming:H2SO4 = 1:3:12) and formula two  (HNO3:HNO3 Fumming:H2SO4 = 1:1.25:4). The results showed that the preparation of nitrocellulose from dissolving pulp A using blender pretreatment and formula two provided the highest nitrogen level (14.05%). The burn test of nitrocellulose met the smokeless specifications. Furthermore, the functional groups test by FTIR showed the presence of nitro group.Keywords: dissolving pulp, nitrocellulose, propellant, nitrogen content, nitration process  ABSTRAK Salah satu upaya untuk mengatasi ketersediaan kapas yang terbatas adalah dengan menggunakan pulp larut atau pulp rayon yaitu pulp dengan kandungan α-selulosa yang tinggi. Penelitian ini bertujuan untuk mencari formula dan bahan baku yang paling baik untuk pembuatan nitroselulosa sebagai bahan Propellant Nitro Cellulose (PNC) dengan menggunakan berbagai jenis pulp larut komersial. Parameter yang terpenting dalam pembuatan propelan adalah kadar nitrogen harus lebih dari 12,75%. Sebelum proses nitrasi, dilakukan beberapa cara perlakuan awal yaitu menggunakan ballmill, willeymill, dan blender terhadap pulp larut dari jenis kayujarum proses sulfit (A), kayudaun proses kraft (B), dan kayudaun proses sulfit (C). Nitroselulosa dibuat menggunakan dua jenis formula yaitu formula 1 (HNO3:HNO3  Fumming:H2SO4= 1:3:12) dan formula 2 (HNO3:HNO3 Fumming:H2SO4= 1:1,25:4). Hasil penelitian menunjukkan bahwa pembuatan nitroselulosa dari pulp larut A dengan perlakuan awal blender dan menggunakan formula 2 memberikan kadar nitrogen yang paling besar yaitu sekitar 14,05%. Sedangkan uji nyala nitroselulosa memenuhi spesifikasi smokeless dan uji gugus fungsi dengan FTIR menunjukkan adanya gugus nitro.Kata kunci: pulp larut, nitroselulosa, propelan, kadar nitrogen, proses nitrasi

scholarly journals DISSOLVING PULP FROM NON-WOOD PLANTS BY PREHYDROLYSISPOTASSIUM HYDROXIDE PROCESS

2021 ◽  
Vol 55 (1-2) ◽  
pp. 117-124
Author(s):  
AKASH MAMON SARKAR ◽  
JANNATUN NAYEEM ◽  
M. MOSTAFIZUR RAHAMAN ◽  
M. SARWAR JAHAN
Keyword(s):  
Wheat Straw ◽  
Rice Straw ◽  
Potassium Hydroxide ◽  
Dissolving Pulp ◽  
Pulp Yield ◽  
Cellulose Content ◽  
Corn Stalk ◽  
Long Time ◽  
Pulp Production ◽  
Rayon Fiber

The garment industry is the backbone of Bangladesh’s economy, which imports 30000 metric tons of rayon fiber every year. Bangladesh used to have a rayon plant, but it was shut down a long time ago. At present, the establishment of a new rayon plant in Bangladesh has become an objective. As a forest deficient country, non-wood plants need to be explored for rayon grade dissolving pulp production. Therefore, in this paper, prehydrolysis potassium hydroxide (KOH) pulping process has been investigated for dissolving pulp production from rice and wheat straws, corn stalk, dhaincha and jute stick. The lowest prehydrolysis yield was 70.1% obtained for corn stalks and the highest prehydrolysis yield was 92.1% for wheat straw. The KOH cooking of prehydrolysed rice straw, wheat straw and corn stalks with 14% alkali charge produced pulps with kappa numbers of 5.7, 4.5 and 8.8, respectively, while prehydrolysed dhaincha and jute stick needed 18% alkali charge to get a bleachable pulp. Dhaincha showed the highest pulp yield (37.3%) with the highest α-cellulose content (92.24%) and the lowest residual pentosan content (5.37%). Further purification with cold KOH extraction increased purity by 3% for rice straw pulp and by 1% for dhaincha, wheat straw, corn stalks and jute stick pulp. Thus, the dissolving pulp produced in this study by the prehydrolysis KOH process can meet the criteria for rayon grade pulp.

scholarly journals Dissolving Pulp From Eucalyptus Sawdust For Regenerated Cellulose Products

2021 ◽  
Author(s):  
Graciela Viviana Olmos ◽  
María Claudia Taleb ◽  
Fernando Esteban Felissia ◽  
Nanci Vanesa Ehman ◽  
Maria Soledad Peresin ◽  
...  
Keyword(s):  
Raw Materials ◽  
Degree Of Polymerization ◽  
Dissolving Pulp ◽  
Regenerated Cellulose ◽  
Cellulose Content ◽  
Cellulose Carbamate ◽  
Soda Pulping ◽  
Dissolving Pulps ◽  
Regenerated Cellulose Films ◽  
Eucalyptus Sawdust

Abstract This study assesses the possibility of obtaining regenerated cellulose products (beads and films) from eucalyptus sawdust dissolving pulps produced by non-conventional processes, compared with a commercial dissolving pulp as a reference. Eucalyptus sawdust dissolving pulps were obtained by soda pulping followed by two different TCF sequential bleaching processes OOpZ and OOp (where O is oxygen, Op is oxygen reinforced with hydrogen peroxide, and Z is ozone), followed by a cold soda extraction. The characterization of dissolving pulps involved alpha-, beta- and gamma-cellulose content, alkali solubility with 10 wt% (S10), and 18 wt% NaOH (S18) aqueous solutions, and degree of polymerization. Fock´s method was used to measure cellulose reactivity and the alkali solubility in a 9 wt% NaOH aqueous solution at -5 °C to evaluate the pulps dissolving capacity. Dissolving pulps presented high cellulose content (> 93 %, expressed as a-cellulose) and good reactivity (almost 84 %). The dissolving pulps were adequate raw materials for regenerated cellulose products (beads and films) from two cellulose dissolution methods: direct dissolution in NaOH/urea and cellulose carbamate solution. The sequence OOpE (where E is an alkaline extraction) was determined to be a more economically feasible and straightforward process to produce dissolving pulp than OOpZE. The experimental pulps showed the expected characteristics of the dissolving pulp to obtain regenerated cellulose products. However, it is necessary to deepen the study of producing regenerated cellulose films with enhanced mechanical properties from experimental dissolving pulps, solvents, coagulation, and regeneration conditions.

Kraft pulp yields and wood properties of fertilized red spruce

1980 ◽  
Vol 10 (2) ◽  
pp. 183-189
Author(s):  
Robert K. Shepard Jr. ◽  
James E. Shottafer ◽  
Joseph M. Genco
Keyword(s):  
Kraft Pulp ◽  
Lignin Content ◽  
Volume Growth ◽  
Wood Properties ◽  
Kappa Number ◽  
Red Spruce ◽  
Unit Weight ◽  
Pulp Yield ◽  
Average Yield ◽  
Posttreatment Period

Red spruce (Picearubens Sarg.) near Princeton, Maine, U.S.A. fertilized with 168 kg N/h in 1970 increased in volume growth by nearly 50% over pretreatment rates during the 8-year posttreatment period; specific gravity was not affected. Average pulp yield per unit weight of posttreatment wood from fertilized trees was 1.9% greater than average yield from pretreatment wood, but rejects increased by 2.2% and kappa number by 17.7 mL. Average pulp yield per unit weight of posttreatment wood from unfertilized trees was 1.2% less than from pretreatment wood; rejects were 0.4% less and kappa number 2.6 mL higher. Fertilization increased the lignin content of posttreatment wood by about 3% and the resin content by 2%. Ash content also increased after fertilization.

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