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121.
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Khalid Muzaffar 《Drying Technology》2016,34(7):802-809
The potential of maltodextrin (DE 20) and soya protein isolate (SPI) in spray drying of tamarind pulp was compared. Powder recovery was zero when the tamarind pulp was spray dried alone. A greater amount of maltodextrin (MD; 55%) was required for successful spray drying of tamarind pulp, whereas a small amount of SPI (20%) was needed for the same purpose. The study revealed that the mechanism for the increase in product recovery with the addition of MD is due to the increase in overall glass transition temperature of tamarind pulp powder. However, using SPI, preferential migration of the protein to the surface of droplets/particles resulting in the formation of a glassy skin was responsible for a reduction in stickiness between the particles and dryer wall and hence increased the powder recovery. The potential of SPI in reducing powder hygroscopicity was almost comparable to that of MD, confirming its efficiency as a drying aid. Tamarind pulp powders produced with SPI had a larger particle size with a wrinkled particle surface morphology and high flowability compared to powders produced with MD. The study showed the excellent potential of SPI as a drying aid in production of quality tamarind pulp powder. 相似文献
123.
The operating conditions for the autohydrolysis of eucalyptus wood were optimized with a view to maximizing hemicellulose extraction while preserving the integrity of glucan. The influence of the operating conditions used in the soda–anthraquinone pulping of the solid phase resulting from the autohydrolysis process was examined. Autohydrolysis of the raw material at a liquid/solid ratio of 8 kg water/kg material at 180°C for 30 min was found to provide a commercially useful liquid phase containing most of the starting hemicellulose. The autohydrolysis treatment allowed the subsequent production of soda–anthraquinone cellulose pulp and paper with properties as good as or even better than those obtained without the pretreatment. 相似文献
124.
Naveen Kumar Chenna Pablo Piovano Christian Järnefelt Tapani Vuorinen 《木材化学与工艺学杂志》2016,36(5):318-328
An oxygen delignified eucalyptus kraft pulp was bleached by applying a catalytic amount of a tertiary amine, 1,4-diazabicyclo[2,2,2]octane, and hypochlorous acid at varying pH, temperature, and time. The bleaching filtrate was analyzed for chloroform and AOX and the pulp for residual lignin, hexenuronic acid, and OX. In comparison with chlorine dioxide bleaching, the novel catalytic bleaching (pH < 6) generated only traces of chloroform and low contents of AOX and OX. Separate catalytic oxidations of authentic hexenuronic acid showed that it was a major precursor of chloroform. The results demonstrate a practical way to reduce organochlorine formation in pulp bleaching and provide new understanding on the reaction pathways that yield chloroform. 相似文献
125.
英落菱镁矿选矿试验研究 总被引:1,自引:0,他引:1
针对菱镁矿矿石中脉石杂质的赋存特点,采用常规反正浮流程,使用Na2CO3反浮矿浆调浆,六偏磷酸钠加水玻璃抑制白云石和硅酸盐脉石杂质,并结合浮选前脱泥的工艺,达到了镁钙硅有效分离的目的,较常规工艺提高了浮选精矿指标。 相似文献
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Bianca Moreira Barbosa Jorge Luiz Colodette Dalton Longue Júnior Fernando José Borges Gomes Daniela Correia Martino 《木材化学与工艺学杂志》2014,34(3):178-190
This study focused on the production of furfural from agricultural and industrial biomass residues by a hydrodistillation process. Corncobs, sugarcane bagasse, and eucalypt wood were treated with sulfuric, hydrochloric, and phosphoric acids as catalysts, with different acid concentrations (1.5 to 5.2 mol.L ?1). In addition, the eucalypt liquor from the auto-hydrolysis, kraft-dissolving pulp production process was also investigated as a source of furfural, using sulfuric and hydrochloric acids as a catalyst (0.9 and 3.9 mol.L ?1) . Furfural yields of 30.2, 25.8, and 13.9% were achieved for corncob, sugarcane bagasse, and eucalypt wood, respectively, on the basis of biomass dry weight. The efficiency of conversion from pentose to furfural using eucalypt liquor from the auto-hydrolysis kraft process was 71.5% using HCl 3.9 mol.L ?1 . Due to the presence of a high amount of pentose, corncob produced the highest amount of furfural, followed by sugarcane bagasse and then eucalypt wood. 相似文献
128.
The pre-hydrolysis liquor (PHL) of the kraft-based dissolving pulp production process is currently sent to the recovery boiler and incinerated. However, PHL contains about 5–8% lignocelluloses that can be utilized in the production of value-added chemicals. In this study, a process for producing xylitol from hemicelluloses in PHL is developed. This process involves several acidification, neutralization, adsorption (along with reactivation) and evaporation stages. The mass balance indicates that 533 kg/h xylitol (with 99% purity), 187 kg/h lignin, 806 kg/h basic ferric acetate, and 1600 kg/h gypsum can be produced from 41,670 kg/h PHL. The energy balance shows that the evaporators are the largest consumers of energy, while the reactivation kiln, acidification, neutralization, and precipitation processes generate some heat. Overall, 41% conversion of xylose to xylitol is achieved. 相似文献
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130.