La改性MCM-41在线催化提质生物油研究

选取油菜秸秆为试验原料,采用浸渍法对MCM-41分子筛进行不同负载量的La改性,利用La/MCM-41分子筛在两段式反应器上进行生物质真空热解在线催化提质制备生物油的试验研究。通过XRD、SEM、Py-IR等方法对MCM-41分子筛进行了表征分析,研究了金属La的引入对生物油有机相理化特性的影响。结果表明,经La改性后的MCM-41保持了载体高度有序的六方型结构,且La/MCM-41表面B酸和L酸的酸量进一步增强;La/MCM-41分子筛能有效降低生物油有机相中酸、醛、酮类等物质的含量,提高烃类物质的含量;当La负载量为5%时,生物油有机相产率增加到18.83%,p H值显著提高并趋向中性,有机相热值高达33.69 MJ/kg,有机相中烃类物质相对峰面积达到34.59%,且以单环芳香烃为主。

In-suit Catalytic Online Upgrading of Bio-oil over La/MCM-41

The rape straw was chosen as experiment materials, and different concentrations of La/MCM-41 were prepared by the impregnation method, then online upgrading of rape straw pyrolysis vapors was performed over La/MCM-41. The modified catalysts were characterized by XRD, SEM and Py-IR, respectively. The influence of the introduction of La on the physical and chemical characteristics of organic phase of bio-oil was analyzed. The results showed that La/MCM-41 had the standard MCM-41 structure and typically hexagonal ordered structure, the surface of La/MCM-41 had more acid of Bronsted acid sites and Lewis acid sites. The organic phase included a variety of organic compounds, such as acid, aldehyde, ketone, alcohols, hydrocarbons and others. The modified MCM-41 catalyst can effectively remove the acid, aldehyde and ketone contained in the bio oil organic phase. At the same time, when the La was loaded up to 5%, the bio oil organic phase achieved a high yield rate to 18.83% and better physciochemical properties. The heating value of organic phase was up to 33.69MJ/kg and the content of hydrocarbon was increased significantly to 34.59% and mainly with monocylic aromatics hydrocarbons, which reduced the content of oxygen in oxygenated compounds. The research result would provide the reliable theoretical basis and experimental basis for the efficient utilization of biomass and the further modification of MCM-41 molecular seive.