Soda-anthraquinone Process Research Articles

Dissolving pulp and furfural production from jute stick

AbstractIn this paper, dissolving pulp is produced from jute stick and jute fiber mixture in pre-hydrolysis soda-anthraquinone process. The overall pulp yield was 30.7 % with kappa number 14.8 at the conditions of 18 % alkali charge for 2 h cooking at 170 °C. The purity of the produced pulp was 94.1 % with residual pentosan content of 4.64 %, which improved to 95.3 % with residual pentosan content of 3.7 % by cold alkali extraction process. The prehydrolysis liquor from the jute stick – jute fiber mixture contained 5.07 % xylose, which was converted to furfural by varying H2SO4concentration, time and temperature. The maximum furfural yield (60.5 %) was obtained at the conditions of 0.1 N H2SO4for 60 min at 170 °C. Further increase of reaction parameter decreased furfural yield.

Effect of prehydrolysis on pulping and bleaching of Acacia auriculiformis A. Cunn. ex Benth.

Prehydrolysis prior to pulping shows a beneficial effect in subsequent delignification and bleaching. Prehydrolysis of Acacia auriculiformis produced higher pulp yield in soda and soda-anthraquinone processes at similar kappa number than non-prehydrolyzed kraft process. In D0EpD1 bleaching sequences, delignification (DoEp kappa) and bleachability were better for prehydrolyzed A. auriculiformis pulp in the pulping processes studied. The lignin from prehydrolyzed wood chips was characterized with lower molecular weight and slightly higher phenolic hydroxyl group. This suggested the depolymerization of lignin in prehydrolysis process.

Variation of Chemical and Morphological Properties of Different Parts of Prunus Amygdalus L. and Their Effects on Pulping

Chemical and morphological of Prunus amygdalus L. characterization (shells and stems) were studied in order to assess their potentiality for chemical pulp. In this work, a simple, rapid and sensitive analytical method for the determination of monosaccharide composition in almond shells and stems polysaccharide was developed and validated. The soda-anthraquinone process was also applied in order to evaluate pulp properties. The effects of delignification and bleaching process were statistically investigated by employing response surface methodology. The isolated fibers were investigated and characterized using several techniques such as gel permeation chromatography, X-ray diffraction, morfi analyzer and scanning electron microscope. The obtained results can be considered as a potential source of cellulose for the production of cellulose derivatives, cellulose pulp for papermaking applications and natural fibres reinforced polymer composite.

Optimization of the soda-ethanol delignification stage for a rice husk biorefinery

The aim of this work was to optimize the delignification of the hemicelluloses-free fraction of rice husk to obtain fractions of lignin, cellulose, and inorganics, which could be valorized in the context of the rice husk biorefinery. The hemicelluloses were pre-extracted from the raw material by dilute sulfuric acid, and a soda-ethanol-water process was used for delignification. Two experimental designs were carried out to evaluate different ranges of the same variables (strong and light conditions), aiming to promote maximal delignification or delignify while protecting carbohydrates. The optimal delignification points were obtained using 13 and 8% of NaOH (%w/w on solid material), in a 50:50 and 54:46 ethanol:water solution. In these conditions, 94.3 and 90.1% of lignin and almost 100 and 40% of inorganics were removed from the solid, respectively. The used soda-ethanol-water process can be defined as a soda process additivated with ethanol, showing significant advantages over soda-anthraquinone process for the fractionation of lignocellulosic materials.

Variation of morphological and chemical properties of three varieties of jute stick

Pulp property of a lignocellulosic material depends upon its morphological characteristics and chemical constituents it. Shabuj Pat (CVL-1) variety from Corchorus capsularis and BJRI Tossa Pat 4 (O-72) and BJRI Tossa Pat 5 (O-795) varieties from Corchorus olitorius of jute are mostly grown in Bangladesh. This study deals on morphological and chemical properties of these three varieties of jute stick to assess their suitability for pulp production. The results were significantly differed among the varieties and within the variety. The ?-cellulose content was almost the same in the variety of CVL-1 and O-795. In the same variety, the middle portion contained the largest amount of alpha-cellulose and the top portion contained the lowest. Klason lignin content varied from 24.2 to 26.8%. Fibre length was significantly same for all the three jute sticks but the width and slenderness ratios were different. Pulp yield in soda anthraquinone process was nearly the same in all these varieties around 44% at kappa number 15.Bangladesh J. Sci. Ind. Res. 51(4), 307-312, 2016

Chemical and Mechanical Properties of Yellow Poplar Pulp Produced by Formic Acid- Hydrogen Peroxide Pulping

TFormic acid-hydrogen peroxide (or performic acid) pulping process needs milder reaction condition than other chemical pulping process. Two-step formic acid-hydrogen peroxide pulping process can produce the chemical pulp with similar pulp yield and lignin content compared with soda-anthraquinone process. Formic acid-hydrogen peroxide pulp can be produced less xylan content than other alkaline pulps, which favor for dissolving pulp production. Formic acid-hydrogen peroxide pulp showed better response beating than soda-anthraquinone(AQ) pulps with reaching target freeness with less beating. Also, formic acid-hydrogen peroxide pulp had better tensile index at similar freeness level compared with soda-AQ pulps.

Paulownia as raw material for solid biofuel and cellulose pulp

Abstract The influence of the process conditions of pulping of a trihybrid clone Paulownia on pulp properties in the soda-anthraquinone process has been investigated. A composite central experimental design and a multiple regression were used to find the relationship between independent process variables and pulp properties. The ash content (8.9 g kg −1 ) is lower and cellulose content (440 g kg −1 ) is higher than those found for other species of Pauwlonia and other energetic crops. The elemental composition has a low content in S and N (2.1 g kg −1 ) in comparation with poplar or willow. With a gross heating value of 20.3 MJ kg −1 . This is somewhat higher than those for hardwood, slightly higher than those for Pinus pinaster and softwood, and much higher than those for residues of food plants and agricultural crops. This supports the use of the genus Paulownia as an energy crop. Fiber length (0.97 mm) is similar to hardwoods and suitable physical characteristics of paper sheets (tensile index) and acceptable chemical characteristics and yield pulping could be obtained by operating at low-intermediate temperature (163–171 °C) and alkali concentration (200 g kg −1 ) and high or medium values for operation time (120–150 min). The pulp obtained at these conditions has suitable chemical (pulp) and physical (paper sheets) characteristics: yield (470 g kg −1 ), ethanol-benzene extractives (22.2 g kg −1 ), holocellulose contents (960 g kg −1 ), α-cellulose contents (758 g kg −1 ), lignin contents (82.8 g kg −1 ), Shopper–Riegler degree (23.2 °SR), and tensile index (36.0 kN m kg −1 ).

Optimization the soda-AQ process for cellulose pulp production and energy content of black liquor from L. leucocephala K360

A commercial variety of Leucaena leucocephala K360 was used for pulp production and papermaking employing the soda-anthraquinone process. Also, the chemical and energy contents of the resultant black liquors were determined to simultaneously optimize: pulp and paper production and energy generation. A process temperature of (185°C), an operating time of (120min) and an active alkali concentration of (21%) provided sheets of paper with good strength (tensile index of 12.12Nm/g, burst index of 0.38kPam2/g, tear index of 1.29mNm2/g and a Kappa number of 20.5) and black liquor with a greater calorific value (14.1MJ/kg) than that obtained with higher active alkali concentrations.However, reducing the active alkali concentration to a level in the low operation range led to less marked degradation of cellulose and allowed paper sheets with good properties to be obtained and energy to be optimally produced from the black liquor.

Effect of pre-extraction on soda-anthraquinone (AQ) pulping of rice straw

The effect of hot-water and alkaline pre-extraction of rice straw on soda-anthraquinone pulping was carried out. The pre-extraction with hot water at 150°C for 1h dissolved 34.7% biomass and the pre-extracted liquor comprised of 16.6% sugars, 6.7% lignin, 6.6% acetic acid and other unknown products. But the pre-extraction with 1% NaOH at 100°C for 1h dissolved 10.2% sugars, 5.1% lignin and 10% acetic acid from rice straw. Pre-extracted rice straw was cooked by soda-anthraquinone process with varying alkali charges. The pulp from pre-extracted rice straw was low in kappa number with reduced pulp yield. The drainage resistance (°SR) improved obviously on pre-extraction of rice straw. Pulp strength properties such as the tensile index and the burst index were found to be lower, but the tear index was higher both with hot-water and alkaline pre-extraction. After bleaching, the gaps of the overall pulp yield and strength properties between pre-extracted and non-extracted rice straw became narrower. The alkaline pre-extraction showed improved yield and properties compared with hot-water pre-extracted rice straw.

Caractéristiques papetières de la pâte de bois de thuya de Berbérie (Algérie) (Tetraclinis articulataVahl) obtenue par un procédé soude-anthraquinone

Characteristics of the pulp and paper of de (Algeria) (Tetraclinis articulata Vahl) obtained by soda-antraquinone process. The coniferous trees of the thuya de Berberie (Tetraclinis articulata Vahl), from the North Africa (Algeria) is commonly grown as a coppice stand. The biomass of thuya, and especially its wood, can be transformed in pulp by the paper and pulp industry throughout the soda cooking process with the help of the anthraquinone (AQ). The young wood (20 years-old) is well delignified in the soda-anthraquinone process, in the usual conditions applied to the resinous species, in the cooking time schedule of 145 min with the level of 165 ◦ C of temperature. The pulp yield of raw material obtained is 43.3% (oven dried wood), with a kappa number of: 33.6. In the same cooking conditions, the mature wood (60 years-old) can be also treated, but with some lower delignification level. thuya / delignification / soda-anthraquinone / pulp yield / Kappa number

5595628 Production of pulp by the soda-anthraquinone process (SAP) with recovery of the cooking chemicals : Gordon Otto W; Plattner Eric; Doppenberg Frank Apples, Switzerland assigned to Grant S A

5595628 Production of pulp by the soda-anthraquinone process (SAP) with recovery of the cooking chemicals : Gordon Otto W; Plattner Eric; Doppenberg Frank Apples, Switzerland assigned to Grant S A

Soda-anthraquinone pulping of Hibiscus sabdariffa (karkadeh) and Calotropis procera from Sudan

Two potential raw materials ( Hibiscus sabdariffa var. sabdariffa — karkadeh — and Calotropis procera — usher) grown in Sudan were examined to determine their suitability for the production of papermaking pulp. Their anatomical, physical, morphological and chemical characteristics and fibre dimensions are reported. Both species were pulped by the soda-anthraquinone process and the usher also by a chemimechanical process (CMP). The soda-anthraquinone pulping of core alone or the whole stem of karkadeh gave good yields (47–49%) of bleachable pulp at a reasonable alkali charge (22% as NaOH) and 0·13% AQ. The mechanical properties of the whole stem were best and it seems pulping to no rejects is most suitable for whole stem pulping. The soda-AQ pulping of usher with the same alkali level gave acceptable yields (43–46%), with mechanical properties at the lower end for tropical pulpwoods. Although the pulps looked well cooked it was difficult to determine their residual lignin due to the presence of unknown phenolics. The CMP gave a high-yield of pulp (73%), with good properties, suitable for paperboard and corrugated medium. The brightening trials, with hydrogen peroxide, of CMP did not much improve the brightness. Addition of guar gum (0·4% on oven-dry pulp) during beating or treatment of refined pulp with the enzyme Lyftase 40 A (0·4% on oven-dry pulp) gave better mechanical properties at a freeness similar to the control.

The thermal stability of some pulping materials

The thermal stabilities of three annual plants (reed, kenaf and Glycyrrihiza glablra L.) are studied. Various types of pulps were prepared from reed stalks by employing the soda, kraft and soda-anthraquinone processes. Their thermal stabilities are reported. It is shown that the thermal stability measured thermogravimetrically depends, to some extent, on the amount of lignin remaining in the raw materials, i.e. the kappa number. The activation energy of the decomposition process and the decomposition temperatures of the pulps are also reported.

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

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