木质纤维全组分微球的制备及其性能调控研究

According to the National Guideline on Medium- and Long-Term Program for Science and Technology Development (2006-2020), the comprehensive utilization of lignocellulose is one of the national key development areas. The production of biofuels, biochemicals, and biocomposites from renewable lignocellulose is attracting much attention around all over the world due to the increasing concerns on resources, fuels, and environment. In this project, magnetic lignocellulose microsphere will be prepared directly from lignocellulose in novel solvents ionic liquids, dimethyl sulfoxide (DMSO) /N-methylimidazole (NMI), or DMSO/lithium chloride (LiCl). The preparation routes for the microsphere will be established. The microspheres will be comparatively prepared from lignocellulose and its isolated components cellulose, hemicelluloses, and lignin to elucidate the behavior of the components during the preparation. The adsorption of heavy metal ions, oil or organic contaminants onto the magneticmicrosphere will be evaluated. The enhancement of the microsphere will be also explored by chemical modification and the introduction of macromolecular chitosan. This research will establish the procedure to produce the magnetic lignocellulose microsphere with many advantages including easily recycling and high adsorption capacity. This research will allow the direct utilization of lignocellulose without fractionation, which reduces environmental pollution and enhances resource savings. It is very important and significant to improve the utilization efficiency of renewable bioresources, establish the scientific basis for the alternative to fossil fuels, and enhance the economic and social benefits.

农林生物质综合开发利用是国家重点发展领域——农业中的优先发展主题之一(2006-2020)，由可再生木质纤维资源转化获得功能材料、生物能源和平台化学品成为研究热点。本项目以国家重大需求为导向，以木质纤维全组分利用为切入点，选用离子液体、二甲基亚砜/1-甲基咪唑、二甲基亚砜/氯化锂等新型溶剂体系为介质，以Fe3O4纳米粒子为磁性载体，构建木质纤维磁性微球的制备途径；通过木质纤维全组分与分离组分纤维素、半纤维素和木质素的对比研究，阐明各组分在微球成型过程中的变化和行为，探讨各组分对成球途径、形貌和微球性能的影响，揭示成球机制；对磁性微球吸附重金属离子性能进行探索性应用研究；通过化学改性和高分子掺杂对微球进行其成球和应用性能调控，揭示微球性能调控机理，提高微球性能。这一研究将为农林生物质综合开发利用提供理论依据和科学导向，具有一定的科学意义和价值。

本项目围绕木质纤维利用展开研究，以木质纤维及其分离组分为原料，以离子液体、二甲基亚砜/1-甲基咪唑、二甲基亚砜/氯化锂、碱/尿素水溶液等新型溶剂体系为介质，对比研究生物质微球的制备路径，阐明了各组分在微球构建过程中的差异化表现，揭示了各组分的作用机制，以Fe3O4纳米粒子为磁性载体建立了木质纤维磁性微球的制备方法。以聚乙烯亚胺、吡啶三氧化硫加合物、苯三酸酐、聚醚酰胺等为改性剂，阐明了衍生化机理，探讨了先成球再衍生化、先衍生化再成球等两种路径对微球性能的影响，建立了木质纤维衍生化对微球的性能调控途径，揭示了调控机理，制备了可重复利用、易于再生、强重金属离子吸附能力的木质纤维微球。以木聚糖、壳聚糖、海藻酸钠等为掺杂物，建立了生物质掺杂共混制备生物质复合微球的方法，探讨了微球性能调控途径，研究了生物质复合微球对多种金属离子的吸附性能和吸附动力学。以海藻酸钠、聚乙烯亚胺、丙烯酰胺、聚丙烯酰胺、壳聚糖等为改性剂或掺杂剂，研究了木质纤维及其分离产物等生物质制备化学/物理复合水凝胶的制备途径，制备了系列生物质水凝胶，探讨了水凝胶对重金属离子的吸附性能，阐明了吸附模型和吸附机理。研究结果为生物质高值化利用提供了理论依据和科学导向。.. 通过四年的努力探索，研究成果已发表学术论文14篇，其中在国内期刊发表2篇，SCI收录论文12篇（均发表在一区期刊Q1上），培养研究生9名。.