Removal of lignin from corn straw by ionic liquid alkali solution

doi:10.16085/j.issn.1000-6613.2017-1908

Abstract

Abstract: Biomass is a rich source of renewable resources. The saccharification and fermentation efficiency of the biomass can be improved by removing the lignin from the biomass. The temperature,time and solid-liquid ratio were studied by using the 1-allyl-3-methylimidazolium chloride aqueous ionic liquid containing NaOH to treat corn straws. The reaction conditions were optimized by a central composite design. The compositions and structures of the straw before and after the treatment were compared. The experimental results showed that,at the temperature of 86.8℃,time of 1.48h and solid-liquid ratio of 1:9g/mL,the content of cellulose in the straw was 83.69%,the content of lignin was 3.29%,and the removal rate of lignin was 81.73%;the reaction temperature had the most significant effect on the cellulose content. This work provides insights for the utilization of maize straw.

Key words: biomass, ionic liquids, separation, cellulose, delignification, alkali solution

摘要： 生物质是来源丰富的可再生资源，去除生物质中的木质素是提高生物质的糖化发酵效率的关键。本文利用含NaOH的离子液体氯化1-烯丙基-3-甲基咪唑（[Amim]Cl）溶液对玉米秸秆进行处理，从反应温度、反应时间和固液比3个方面研究其脱除木质素的效果，采用单因素实验和Box-Behnken中心组合实验对反应条件进行优化，对比分析处理前后的秸秆的组成和结构变化。结果表明：在反应温度86.8℃，反应时间1.48h，固液比1∶9g/mL时，处理后秸秆中纤维素含量达到83.69%，木质素含量为3.29%，木质素脱除率达81.73%，反应温度对纤维素含量影响最显著。本工作可为玉米秸秆的资源化利用提供参考。

关键词: 生物质, 离子液体, 生物分离, 纤维素, 脱木质素, 碱溶液

CLC Number:

TQ35

LIU Cheng, LIU Zhen, LI Longfei, ZHANG Shiying, XU Airong. Removal of lignin from corn straw by ionic liquid alkali solution[J]. Chemical Industry and Engineering Progress, 2018, 37(05): 1789-1794.

刘程, 刘振, 李龙飞, 张世英, 许爱荣. 离子液体碱溶液脱除秸秆中木质素[J]. 化工进展, 2018, 37(05): 1789-1794.

References

[1] KURIAN J K,NAIR G R,HUSSAIN A,et al. Feedstocks,logistics and pre-treatment processes for sustainable lignocellulosic biorefineries:A comprehensive review[J]. Renewable & Sustainable Energy Reviews,2013,25(5):205-219.
[2] WILDSCHUT J,SMIT A T,REITH J H,et al. Ethanol-based organosolv fractionation of wheat straw for the production of lignin and enzymatically digestible cellulose[J]. Bioresource Technology,2013,135(2):58-66.
[3] LOPES A M D C,JOAO K G,RUBIK D F,et al. Pre-treatment of lignocellulosic biomass using ionic liquids:wheat straw fractionation[J]. Bioresource Technology,2013,142(8):198-208.
[4] BARAKAT A,ROUAU X. Dry fractionation process as an important step in current and future lignocellulose biorefineries:a review[J]. Bioresource Technology,2013,134(4):362-373.
[5] MONLAU F,BARAKAT A,TRABLY E,et al. Lignocellulosic materials into biohydrogen and biomethane:impact of structural features and pretreatment[J]. Critical Reviews in Environmental Science & Technology,2013,43(3):260-322.
[6] HENDRIKS A T W M,ZEEMAN G. Pretreatments to enhance the digestibility of lignocellulosic biomass[J]. Bioresource Technology,2009,100(1):10-18.
[7] YANG D,ZHONG L X,YUAN T Q,et al. Studies on the structural characterization of lignin,hemicelluloses and cellulose fractionated by ionic liquid followed by alkaline extraction from bamboo[J]. Industrial Crops & Products,2013,43(1):141-149.
[8] BI S,PENG L,CHEN K,et al. Enhanced enzymatic saccharification of sugarcane bagasse pretreated by combining O2 and NaOH[J]. Bioresource Technology,2016,214:692-699.
[9] SEOUD O A E,KOSCHELLA A,FIDALE L C,et al. Applications of ionic liquids in carbohydrate chemistry:a window of opportunities[J]. Biomacromolecules,2007,8(9):2629-2647.
[10] ROSEIRO L B. Novel pre-treatment and fractionation method for lignocellulosic biomass using ionic liquids[J]. RSC Advances,2013,3(36):16040-16050.
[11] SWATLOSKI R P,SPEAR S K,HOLBREY J D,et al. Dissolution of cellulose with ionic liquids[J]. Journal of the American Chemical Society,2002,124(18):4974-4975.
[12] 刘振,孙海红,郝静静. 离子液体对玉米秸秆组分的溶解选择性[J]. 可再生能源,2014,32(6):871-875. LIU Z,SUN H H,HAO J J. Selectivity of dissolution for the components of cornstalk with ionic liquids[J]. Renewable Energy Resources,2014,32(6):871-875.
[13] BRANDT A,GRASVIK J,HALLETT J P,et al. Deconstruction of lignocellulosic biomass with ionic liquids[J]. Green Chemistry,2013,15(3):550-583.
[14] 马宁宁. 咪唑类离子液体-水体系对木质素溶解过程的研究[D]. 大连:大连工业大学,2014. MA N N. The study of lignin dissolution in the imidazolium-based ionic liquid-water mixtures[D]. Dalian:Dalian Polytechnic University,2014.
[15] 项婧,李坤兰,魏立纲,等. 离子液体-水体系循环使用对白松木质素提取的影响[J]. 化工学报,2013,64(s1):124-127. XIANG J,LI K L,WEI L G,et al. Effect of recycle of ionic liquid on its performance of white pine lignin extraction[J]. CIESC Journal,2013,64(s1):124-127.
[16] FU D,MAZZA G.. Aqueous ionic liquid pretreatment of straw[J]. Bioresource Technology,2011,102(13):7008-7011.
[17] LI H Y,WANG C Z,CHEN X,et al. Structural elucidation of Eucalyptus lignin and its dynamic changes in the cell walls during an integrated process of ionic liquids and successive alkali treatments[J]. Bioresource Technology,2016,222:175-181.
[18] AN Y X,LI N,ZONG M H,et al. Easily measurable pH as an indicator of aqueous cholinium ionic liquid pretreatment effectiveness of lignocellulose[J]. RSC Advances,2014,4(98):55635-55639.
[19] ZHANG H,WU J,ZHANG J,et al. 1-Allyl-3-methylimidazolium chloride room temperature ionic liquid: a new and powerful nonderivatizing solvent for cellulose[J]. Macromolecules,2005,38(20):8272-8277.
[20] CHANG K L,CHEN X M,WANG X Q,et al. Impact of surfactant type for ionic liquid pretreatment on enhancing delignification of rice straw[J]. Bioresource Technology,2017,227:388-392.
[21] SLUITER A,HAMES B,RUIZ R,et al. Determination of structural carbohydrates and lignin in biomass,NREL/TP -510-42618[R]. Golden:Laboratory Analytical Procedure(LAP),2011.
[22] SLUITER A,HAMES B,RUIZ R,et al. Determination of sugars byproducts and degradation products in liquid fraction process samples,NREL/TP-510-42623[R]. Golden:Laboratory Analytical Procedure(LAP),2008.
[23] 王琳琳,魏立纲,马英冲,等. 1-丁基-3-甲基咪唑氯盐离子液体水溶液对纤维素的作用[J]. 化工学报,2015,66(s1):32-37. WANG L L,WEI L G,MA Y C. et al. Effect of 1-butyl-3-methylimidazolium chloride-water mixtures on cellulose[J]. CIESC Journal,2015,66(s1):32-37.