不同钛源改性HZSM-5耦合低温等离子体放电催化生物油提质反应的性能

以不同Ti源(金红石型TiO2、锐钛型TiO2、中间价态钛氧化物及常规TiO2)对HZSM-5分子筛进行改性，并采用XRD、BET、Py-IR、FT-IR、TG-DTG和TEM方法对改性催化剂进行表征；利用改性催化剂耦合低温等离子体放电(Cold Plasma Discharge, CPD)进行在线催化生物油提质反应，以光学发射光谱(Optical Emission Spectroscopy, OES)在线监测反应中产生的活性自由基，分析催化剂改性对精制生物油产率、燃料品位和化学组成的影响。结果表明：在CPD诱导下，锐钛型TiO2和中间价态钛氧化物改性催化剂性能较高，产生更多活性自由基，生物油产率和高位热值提高，产物中烃质量分数提高，结焦率降低；金红石型TiO2改性催化剂性能变差；常规TiO2改性催化剂酸性增强，但与CPD无协同作用，催化剂性能变化不明显。

Catalytic Upgrading of Bio-oily by Different Ti Sources Modified HZSM-5 Coupled With Cold Plasma Discharge

HZSM-5 zeolites were modified with different Ti sources by impregnation method. Rutile TiO2, anatase TiO2, medium valent titanium oxide and conventional TiO2 were loaded, correspondingly. The modified catalysts were characterized with different methods including XRD, BET, Py-IR, FT-IR, TG-DTG and TEM. Online catalytic upgrading of bio-oils was studied by using different modified catalysts coupled with Cold Plasma Discharge (CPD). Active free radicals produced in the reaction process were monitored by Optical Emission Spectroscopy (OES). Effects of modification on the yield, fuel grade and chemical composition of refined bio-oils were investigated. Experimental results show that, under the induction of CPD, anatase TiO2 and medium valent titanium oxide have better catalytic performance. They can produce more active radicals, improve the yield of bio-oils and generate more bio-oils with high heating capacity, increase hydrocarbon content in the products, and reduce coke yield. Modification with rutile TiO2 results in poor catalyst conversion performance. The acidity of catalyst can be enhanced with conventional TiO2 modification, however, the modified catalyst has no synergistic effect with CPD, and thus cannot improve its catalytic performance.