木素-二氧化硅纳米复合物制备与表征初步探索

Preliminary Exploration of the Preparation of Lignin-silica Nano Composites and Their Characterization

关键词:  玉米秸秆  纤维素乙醇残渣  木素-二氧化硅纳米复合物

Key Words:corn stalks  cellulosic ethanol residue  lignin-silica nano composites

摘要:以玉米秸秆发酵生产纤维素乙醇得到的残渣为原料,NaOH为溶剂,HCl为酸沉淀剂,利用酸沉淀法制备木素-二氧化硅纳米复合物。采用红外光谱、扫描电镜（SEM）、热重检测（TGA）和粒径测定等手段,研究反应体系pH值和温度对复合物形貌、组成成分及含量的影响,确定制备木素-二氧化硅纳米复合物的最佳工艺条件。结果表明,当反应温度30℃、pH值7时,制备出的复合物中二氧化硅的质量分数为75.05%,且复合物分散性较好,比木素具有更好的热稳定性。通过粒径分布分析,制备的木素-二氧化硅纳米复合物粒径为95 nm的粒子数量占20.2%。

Abstract:The lignin-silica nano composites were prepared by extraction of the silica from the fermentation residues after producing alcohol of corn stalks with NaOH aqueous solution and followed by precipitation with hydrochloric acid. The effects of pH and temperature on morphology and composition of the composites were evaluated through the analysis of FT-IR, SEM, TGA and dynamic light scattering (DLS). The results showed that the nano lignin-silica composites with excellent properties were prepared with a pH of 7.0 and a reaction temperature of 30℃. The weight content of silica in the composites obtained in this condition was 75.05%, and the composites were easily to be dispersed and its thermal stability was better than lignin. The analysis of DLS showed that the number of nanoparticles with the size of 95 nm accounted for 20.2%.