scholarly journals Effect of bleaching using sodium hydroxide on pulp derived from Sesbania grandiflora

2021 ◽  
Vol 6 (1) ◽  
pp. 1-3
Author(s):  
Tan Shioa Wei ◽  
Boon Jia Geng ◽  
Low Hui Qi ◽  
Goh Kent Tiong ◽  
Kuek Sook Chi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Sodium Hydroxide ◽  
Kraft Pulp ◽  
Bleached Pulp ◽  
Bleached Kraft Pulp ◽  
Short Rotation ◽  
Sesbania Grandiflora ◽  
World Demand ◽  
Optical And Mechanical Properties ◽  
Unbleached Pulp

World demand for paper is increasing. Short rotation pulpwood is needed. Sesbania grandiflora also known as Turi, is a fast growing and straight log species. The scholarly information of Turi as pulpwood are still limited. This paper aims to provide information of sodium hydroxide effect on the paper made from pulp derived from Turi. Sodium hydroxide is a common chemical using as part of full stage chemical bleaching in pulp industrial. Kraft pulp that produced using Turi, was bleached with sodium hydroxide at 3%, 6% and 9% based on pulp weight, respectively. Unbleached pulp was served as blank test. The optical and mechanical properties of handsheet paper made from bleached kraft pulp were evaluated according to TAPPI standard. The brightness and opacity of handsheet made from bleached pulp were improved with increasing the concentration of sodium hydroxide. The mechanical properties of handsheet were improved with using 3% sodium hydroxide and gradually decreased after 3% sodium hydroxide. In conclusion, sodium hydroxide is potential to improve optical properties of Turi pulp and improve the mechanical properties of paper made from Turi pulp at certain level. Excessive usage of sodium hydroxide brings adverse effect to mechanical properties of paper made from Turi pulp.

scholarly journals Nanostructured Films Produced from the Bleached Pinus sp. Kraft Pulp

2019 ◽  
Vol 26 (4) ◽  
Author(s):  
Lívia Cássia Viana ◽  
Graciela Ines Bolzon de Muñiz ◽  
Washington Luiz Esteves Magalhães ◽  
Alan Sulato de Andrade ◽  
Silvana Nisgoski ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Kraft Pulp ◽  
Physical And Mechanical Properties ◽  
Compact Structure ◽  
Nanostructured Films ◽  
Bleached Kraft Pulp ◽  
Lower Porosity ◽  
Density Values ◽  
Number Of Passes

ABSTRACT This study investigates the physical and mechanical properties of nanostructured films produced from Pinus sp. kraft pulp. To obtain the nanocellulose, the bleached kraft pulp was submitted to six different grinding regimes: two, five, ten, 20, 30, and 40 passes through the grinder. The influence of the number of passes was evaluated through the films’ physical and mechanical properties. The results show that the nanofibers reduced the thickness and considerably increased the density values of the fabricated films. The tensile strength increased more than 300% and the burst index was ten times higher in relation to normal papers. The more compact structure and lower porosity caused by the larger contact surface between nanofibers in the nanostructured films resulted in higher values of density, tensile strength, and burst resistance.

scholarly journals Canadian Pulp and Paper in World Trade

1978 ◽  
Vol 54 (3) ◽  
pp. 147-151
Author(s):  
D. B. Cooke
Keyword(s):  
Kraft Pulp ◽  
Paper Industry ◽  
Pulp And Paper ◽  
Forest Resource ◽  
Pulp Industry ◽  
Bleached Kraft Pulp ◽  
Self Sufficiency ◽  
Excellent Growth ◽  
World Demand ◽  
Pulp Fibres

Canada still commands a major position in two key world pulp and paper products which come from our softwood forest resource — newsprint and woodpulp. In 1977 Canada produced 40% of the newsprint and 30% of the softwood bleached kraft used in the free world. Fine papers, linerboard and tissue grades of paper are made chiefly for the domestic market and are all tariff protected.After 30 years of excellent growth, the future prospects for the Canadian pulp and paper industry are clouded by: slower world demand for paper and board, increased self-sufficiency for newsprint and pulp in many of Canada's key markets, continuing trends to substitution of cheaper pulp fibres for the more expensive softwood bleached kraft pulp, the cornerstone of Canada's pulp industry.

Polyhydric Alcohol Pulping at Atmospheric Pressure: An Effective Method for Organosolv Pulping of Softwoods

Holzforschung ◽  
1999 ◽  
Vol 53 (4) ◽  
pp. 411-415 ◽  
Author(s):  
Yasumitsu Uraki ◽  
Yoshihiro Sano
Keyword(s):  
Mechanical Properties ◽  
Atmospheric Pressure ◽  
Kraft Pulp ◽  
Kappa Number ◽  
Polyhydric Alcohol ◽  
Sodium Chlorite ◽  
Cellulose Content ◽  
Residual Lignin ◽  
Bleached Pulp ◽  
Very High

Summary Polyhydric alcohol pulping was developed to separate components of low-quality softwoods that are produced by thinning and improvement cutting as well as to establish a self-supporting pulping system. Propylene glycol (PG) was superior to ethylene glycol (EG) as solvent for polyhydric alcohol pulping at atmospheric pressure. PG pulping of fir, larch and cedar, with sulfuric acid as a catalyst, gave satisfactory pulps with few rejects and a very low level of residual lignin as compared with EG pulping. The PG pulps were readily bleached to approximately Kappa number 1 and 80% brightness by one treatment with sodium chlorite. The yield of bleached pulp from fir was 44.7% based on chips. The bleached pulps had very high α-cellulose content and crystallinity, and their mechanical properties were similar to those of kraft pulp. Therefore, polyhydric alcohol pulping appears to be promising for pulping of softwoods by an organosolv method.

Pulp delignification with oxygen and copper(II)-polyimine complexes

Holzforschung ◽  
2014 ◽  
Vol 68 (4) ◽  
pp. 377-384 ◽  
Author(s):  
Basile Gueneau ◽  
Nathalie Marlin ◽  
Alain Deronzier ◽  
Dominique Lachenal
Keyword(s):  
Redox Potential ◽  
Kraft Pulp ◽  
Oxygen Activation ◽  
Kraft Lignin ◽  
Kraft Pulps ◽  
Oxygen Delignification ◽  
Mechanical Pulp ◽  
Bleached Pulp ◽  
Carbohydrate Degradation ◽  
Unbleached Pulp

Abstract Ten Cu(II)-polyimine complexes were tested as potential catalysts in oxygen delignification of softwood kraft pulps. The ligands were chosen from the terpyridine and the phenanthroline families, including several neocuproines. One diamine-phenanthrene (daphen) was also investigated. The main purpose was to examine whether the presence of methyl or phenyl substituents would direct the oxidation toward lignin. As a catalyst for comparison, unsubstituted 1,10-phenanthroline was selected, which is known to activate both delignification and carbohydrate degradation during oxygen bleaching of kraft pulp. The variation of ligands was aiming at the complex solubility and redox potential of the parameters. The experiments were performed on a mixture of mechanical pulp and fully bleached kraft pulps, a fully bleached pulp alone, and an industrial unbleached pulp. Concerning the oxygen activation in delignification of kraft pulp, 4,7-diphenyl-1,10-phenanthroline was as good as 1,10-phenanthroline, but appeared to be more selective, which resulted in a higher DPv of cellulose after treatment. This was interpreted by the structural similarities between the ligand and the kraft lignin and by a better stability of the intermediate complex with lignin. Two Cu(II)-phenanthroline derivatives complexes (4,7- and 5,6-dimethyl-1,10-phenanthroline) were also identified as effective oxygen activators for the removal of native lignin.

Characterization of Physical and Mechanical Properties of Bleaching Paper from Rice Straw

2019 ◽  
Vol 891 ◽  
pp. 3-8 ◽  
Author(s):  
Udomdeja Polyium ◽  
Thanapan Boonyaratakalin ◽  
Songsiri Wichiranon
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Rice Straw ◽  
Physical And Mechanical Properties ◽  
Optimal Conditions ◽  
Tear Strength ◽  
Burst Strength ◽  
Bleached Pulp ◽  
Unbleached Pulp

This paper aimed to determine the characteristics of physical and mechanical properties of rice straw hand sheet and investigated the optimal conditions for making rice straw paper. The chemical composition of rice straw determined with the TAPPI standards. The conditions of making paper hand sheet composed of pulping time: 2 hours, 4 hours, pulping temperature: 100°C, 130°C, pulping solvent: 2 wt% NaOH, 4 wt% NaOH and bleaching: unbleached pulp, bleached pulp with 2% H2O2. The paper hand sheet was tested based on TAPPI methods, basic weight TAPPI- T410-om-93, thickness TAPPI- T411-om-89, moisture content TAPPI- T412-om-93, brightness TAPPI T452 om-92, opacity TAPPI standard T 425 om-91, burst strength TAPPI T403 om-97, tensile strength TAPPI T494 om-01, and tear strength TAPPI-T414-om-88. The results showed that the optimal conditions of rice straw hand sheet including pulping time: 2 hours, pulping temperature: 100°C, pulping solvent: 2 wt% NaOH, and bleaching: unbleached pulp gave the highest the physical and mechanical properties form other conditions. This conditions showed as the basic weight 62.27 g/m2, thickness 259.30 µ, opacity 93.34 ISO%, burst strength 64.75 kPa.m2/g, tensile strength 95.33 N.m/g, and tear strength 473.55mN.m2/g. In this condition, the paper hand sheet used at the lowest concentration of pulping solvent and non-bleached, which reduces environmental pollution.

Desorption of Cationic Polyacrylamide from Bleached Kraft Pulp Fibers

1987 ◽  
Vol 19 (5-6) ◽  
pp. 939-951 ◽  
Author(s):  
Clifton F. Warren ◽  
R. Gehr
Keyword(s):  
Adsorption Isotherm ◽  
Total Nitrogen ◽  
Kraft Pulp ◽  
Detection System ◽  
Cationic Polyelectrolyte ◽  
Chemiluminescence Detection ◽  
Pulp Fibers ◽  
Paper Manufacturing ◽  
Bleached Kraft Pulp ◽  
Receiving Water

The adsorption and desorption behaviour of a cationic polyelectrolyte contacted with wood pulp fibers was determined by total nitrogen analysis using a pyrolysis/chemiluminescence detection system. Dialysed polymer generated an adsorption isotherm of higher affinity than did non-dialysed polymer. Capacity adsorption was maximized at pH 7, but decreased in the presence of alum depending on the dosage. Desorption of non-dialysed polymer was caused by changes in pH above or below 7.0 as well as by addition of alum. However for the alum doses typically encountered in paper manufacturing, significant desorption is unlikely. Nevertheless, the contaminants in non-dialysed polymers do hinder adsorption, and effluents from those processes using both alum and polymer may contain quantities of unadsorbed or desorbed polyelectrolytes which could be damaging to receiving water bodies.

Characterization of odorous compounds from bleached kraft pulp mill effluent

1995 ◽  
Vol 31 (11) ◽  
pp. 35-40 ◽  
Author(s):  
B. G. Brownlee ◽  
S. L. Kenefick ◽  
G. A. MacInnis ◽  
S. E. Hrudey
Keyword(s):  
Gas Chromatography ◽  
Kraft Pulp ◽  
Pulp Mill ◽  
Dimethyl Disulfide ◽  
Gas Chromatography Mass Spectrometry ◽  
Pulp Mill Effluent ◽  
Kraft Pulp Mill ◽  
Bleached Kraft Pulp ◽  
Methyl Phenyl Sulfide ◽  
Library Spectrum

Odour compounds in extracts of bleached kraft pulp mill effluent (BKME) have been characterized by olfactory gas chromatography (OGC) and gas chromatography-mass spectrometry. A variety of sulfury odours was detected by OGC in addition to woody and pulp mill-like odours. Three sulfur compounds were identified by comparison of retention times and partial mass spectra with authentic standards: dimethyl disulfide, 3-methylthiophene and thioanisole (methyl phenyl sulfide). Typical concentrations in BKME were 1, 0.05, and 0.5 μg/l, respectively. Their odour intensity is relatively low and they were not detected by OGC. Dimethyl trisulfide was tentatively identified by comparison of its partial mass spectrum with a literature (library) spectrum. Its concentration in BKME was estimated at 0.5-2 μg/l. It corresponded to a skunky odour in the OGC profiles. Efforts to identify another odour peak, eluting just after 3-methylthiophene, with a pronounced alkyl sulfide odour were unsuccessful.

Growth responses of periphyton and chironomids exposed to biologically treated bleached kraft pulp mill effluent

1997 ◽  
Vol 35 (2-3) ◽  
pp. 339-345 ◽  
Author(s):  
M. G. Dubé ◽  
J. M. Culp
Keyword(s):  
Kraft Pulp ◽  
Pulp Mill ◽  
Pulp Mill Effluent ◽  
Growth Responses ◽  
High Concentration ◽  
Wood Extractives ◽  
Kraft Pulp Mill ◽  
Bleached Kraft Pulp ◽  
Low Levels ◽  
High Concentrations

Experiments were conducted in artificial streams to determine the effects of increasing concentrations of biologically treated bleached kraft pulp mill effluent (BKPME) on periphyton and chironomid growth in the Thompson River, British Columbia. Periphyton growth, as determined by increases in chlorophyll a, was significantly stimulated at all effluent concentrations tested (0.25%, 0.5%, 1.0%, 5.0% and, 10.0%). Chironomid growth (individual weight) was also significantly stimulated at low effluent concentrations (≤1.0%). At higher concentrations (5.0% and 10.0%), chironomid growth was inhibited relative to the 1.0% treatment streams. Increases in growth were attributed to the effects of nutrient and organic enrichment from BKPME. The effluent contained high concentrations of phosphorus and appears to be an important source of carbon for benthic insects grazing on the biofilm. In high concentration effluent streams, chironomid growth decreased despite low levels of typical pulp mill contaminants. This suggests that other compounds in the effluent, such as wood extractives, may be inhibiting chironomid growth. These results support findings of field monitoring studies conducted in the Thompson River where changes in periphyton and chironomid abundance occurred downstream of the bleached kraft pulp mill.

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