卷烟滤嘴棒填充纸及嘴棒性能的研究

以卷烟厂废滤嘴棒为原料,对其进行打浆处理,并与植物纤维配抄卷烟滤嘴棒填充纸(CAP纸).实验结果表明,废滤嘴棒经过处理后可以作为CAP纸的原料,并且抄造的CAP纸可使滤嘴棒既具有纸质填充材料吸附性好的优点,又具有醋酸纤维良好弹性和吸味的特点.应用试验结果表明,在吸阻相同的情况下,CAP纸可使滤嘴棒具有较好的降低卷烟焦油性能.     

木质生物质精炼预处理技术研究进展

木质生物质不仅可应用于制浆造纸工业,也可替代有限的石化资源用于生产化学品、合成材料和再生能源等,然而其结构的复杂性限制了其高效转化.预处理技术作为生物质精炼高效转化的关键步骤,已成为世界各国的研究热点.文章对物理法、化学法、物理-化学法和生物法预处理木质生物质技术的国内外研究进展进行了综述,对相应技术的处理效果进行了分析和总结,对预处理技术的发展及其基于制浆造纸工业相结合的前景进行了展望并提出了建议.     

桉木热水预水解过程中木糖反应动力学的研究

研究了桉木热水预水解生成木糖水解液的反应动力学,分别测定了不同热水预水解条件下木糖质量浓度及其降解产物糠醛的质量浓度。研究表明,以木糖质量浓度及糠醛的质量浓度为指标,确定桉木最佳热水预水解条件为:液比1∶8,水解温度170℃,保温时间105 min。此条件下,预水解液中木糖和糠醛质量浓度分别为7. 97 g/L、1. 74 g/L,桉木热水预水解生成木糖的反应活化能为72. 62 kJ/mol。     

N,O-羧甲基壳聚糖的制备及其结构表征

壳聚糖和氯乙酸反应,在低碱浓的条件下合成了水溶性较好的总取代度高、N位取代度低的N,O-羧甲基壳聚糖,并采用单因素实验优化了制备条件,结果表明:当反应温度为90℃,壳聚糖与氯乙酸质量比为1:4时,制备的N,O-羧甲基壳聚糖的取代度为1.567。用红外光谱(FTIR)和热重分析(TGA)对N,O-羧甲基壳聚糖进行了结构表征,发现N,O-羧甲基壳聚糖的N位和O位均引入了羧甲基,但改性后N,O-羧甲基壳聚糖的热稳定性比壳聚糖差,热分解温度比壳聚糖低。     

我国制浆造纸装备科学技术的发展

简要地讨论了制浆造纸装备及其制造业和学科建设的现状和在我国造纸工业发展中的地位和作用,着重探讨了近年来我国制浆造纸装备科学技术取得的进展,同时也讨论了国际先进制浆造纸装备科学技术在我国的应用现状;从科技研发、制造业状况和学科建设等方面对国内外制浆造纸装备科学技术现状进行了比较分析;提出了今后我国制浆造纸装备科学技术发展展望与对策建议.     

Preparation of high crystallinity cellulose nanocrystals (CNCs) by ionic liquid solvolysis

High crystallinity cellulose nanocrystals (CNCs) were successfully prepared from microcrystalline cellulose (MCC) by utilization of 1-butyl-3-methylimidazolium hydrogen sulfate (BmimHSO₄) as both catalyst and solvent. Interestingly, it was found that crystallinity of CNCs was improved with increase in temperature which attributed to selective removal of the amorphous phase of cellulose performed at a higher rate with higher temperature. The successful conversion of MCC to CNCs was supported by HRTEM in which the uniform rod-like shape of CNCs was obtained. CNCs with diameter range from 15 to 20 nm and length range from 70 to 80 nm were successfully produced at 90 °C with BmimHSO₄. In the present work, CNCs synthesized at different temperatures from 70 °C to 100 °C were investigated. The application of BmimHSO₄ as both catalyst and solvent introduced a green chemistry approach as it does not produce any hazardous waste products and is an economical process because the recovery of ionic liquid is high (>90%).     

高效合成树脂在造纸中的应用研究进展

就常用的新型高效合成树脂在造纸工业中的应用和研究进展做了简要的介绍。     

造纸法低定量烟草薄片增强助剂的性能评价

以造纸法制备了低定量烟草薄片,测定了壳聚糖、羧甲基纤维素、羟乙基纤维素和聚乙烯醇的增强性能,及其对烟草浆料和填料留着,以及烟草基片物理性能的影响。研究结果表明,加入壳聚糖的系统助留效果最好,填料留着率提高7.3%;加入羧甲基纤维素和聚乙烯醇的烟草基片具有较好的松厚度和吸液性;加入羟乙基纤维素和壳聚糖的烟草基片分别具有较好的抗干、湿强度。     

Recent developments of hydrogen production from sewage sludge by biological and thermochemical process

Hydrogen is a kind of clean effective resource. Sewage sludge is regarded as a promising material for hydrogen production because it owns a wide range of sources and the methods are consistent with the goal of sustainable development. This work reviews existing hydrogen production technologies from sewage sludge, including photo-fermentation, dark-fermentation, sequential dark- and photo-fermentation, pyrolysis, gasification, and supercritical water gasification (SCWG). Overall comparison for the involving approaches is conducted based on their inherent features and current development status along with the technical and environmental aspect. Results show that sequential dark- and photo-fermentation and pyrolysis have improved hydrogen yields, but the emissions of carbon dioxide are also remarkable. Biological processes have an advantage in cost, but the reaction rates are inferior to those of thermochemical method. Enhancing methods and improvements are proposed to guide future research on hydrogen production from sewage sludge and promote the effectiveness both technically and economically.     

Effect of nutrient supplementation on ethanol production in different strategies of saccharification and fermentation from acid pretreated rice straw

The effect of nutrient supplementation on ethanol production by recently selected thermotolerant yeast (Kluyveromyces marxianus NRRL Y-6860) was investigated in different strategies of saccharification and fermentation employing rice straw pretreated by dilute acid. Among the evaluated strategies, similar ethanol yields (Y_P/S ∼ 0.23 g g⁻¹) were obtained with or without nutrient addition. However, considering the whole process time, the strategy based on simultaneous saccharification and fermentation (SSF), without pre-hydrolysis, was assigned as the most suitable configuration due to the highest ethanol volumetric productivity (1.4 g L⁻¹ h⁻¹), about 2-fold higher in relation to the others. The impact of enzymatic preparation employed in this study was also evaluated on glucose fermentation in semi-synthetic medium. The enzymatic preparation affected both glucose consumption and ethanol production by K. marxianus NRRL Y-6860, but just in the absence of nutrients. Therefore, the enzyme type and loading should be carefully defined, not only by the capital costs involved, but also by the possibility of increasing the fermentation inhibitors.