玉米秸秆的催化微波裂解及生物油成分

近年来，生物质热化学裂解已引起了越来越广泛的兴趣。但常规的生物质热裂解技术（如流化床等）要求细小的生物质原材料，因此粉碎能耗大。而且裂解所得的生物油和合成气产物易受生物质粉末污染。微波裂解虽然能帮助解决这些问题，但目前的微波裂解所得的生物油成分和其他热裂解技术一样，仍然过于复杂，因此尽管生物质热解获取生物油的成本低于生物质发酵所获得的燃料，生物质热解技术也仍未在工业上得到推广应用。该研究旨在帮助解决这一难题。利用玉米秸秆颗粒为原料，采用了4%的硫酸或磷酸的预处理，或者采用氯化物等催化剂直接混入原料，然后利用微波进行催化裂解，并获得气态、固态和液态生物油3种产物。利用气质联用设备（GC-MS），对所得到的液态产物（生物油，Bio-oil）进行成分分析。在大量的试验基础上，该文筛选出的酸预处理，MgCl2、ZnCl2、及AlCl3直接催化是可以使所得的生物油成分简化的实用技术。

Microwave assisted pyrolysis of corn stover pellets with catalysts for bio-oil production and its component

Biomass pyrolysis has attracted significant interest in recent years. However, traditional pyrolysis technologies such as fluidized bed type of pyrolysis technique require biomass to be ground into fine particles which adds a lot of energy input and cost. In addition, bio-oil and syngas products produced are often contaminated by the incomplete reacted biomass materials. Microwave pyrolysis helps solve those problems, however, just like other pyrolysis technologies, the bio-oil products from current pyrolysis technologies including microwave are still very complex in composition, acidic, and not stable, which prevent the commercialization of the pyrolysis technology, even though the cost of bio-oil production from pyrolysis is much less than that of biological approach. The study intends to help solve this exact problem. Corn stover was used as feedstock, and the effects of catalysts on the product selectivity of microwave assisted pyrolysis were investigated. Many kinds of acids, alkali, metal oxides, and salts were tested as catalysts for pyrolysis. The bio-oil compositions were analyzed with GC-MS. It was found that when corn stover pellets were pre-mixed with some kinds of acids, and/or chloride salts prior to microwave assisted pyrolysis, the components of the liquid bio-oil products were very simple. At 8 g catalysts per 100 g corn stover, the GC-MS total ion chromatograms of the bio-oils show only one major furfural peak accounting for about 80% of the area under the spectrum.