含油污泥在ZSM-5沸石上催化热解产物特性

采用U型固定床管式炉研究了含油污泥在ZSM-5分子筛催化剂上的热解产物特性。发现在450℃下未使用催化剂热解时，GC-MS和GC测得的油泥热解油产物中的主要成分为烷烃和烯烃，芳烃含量较低；气体产物中主要为短链烃类，氢气产量较少。而在ZSM-5分子筛的催化作用下，热解油中芳香烃产量达到88.4%，气体产物中的氢气产量和短链烃类产量均明显增加。研究了400～550℃之间分子筛对含油污泥的催化效果，发现ZSM-5在500℃时催化效果最佳，油相产率达到65.6%，油相中的沥青质和胶质含量较低，芳香烃产量达到90.9%。通过热重和XPS分析发现分子筛上的积炭主要以多环芳烃焦炭的形式存在。

Products obtained from catalytic pyrolysis of oily sludge over ZSM-5 zeolite

Catalytic pyrolysis of oily sludge over ZSM-5 zeolite was carried out in a U type fixed-bed tubular reactor. Gas chromatography-mass spectrometry and gas chromatography were employed to investigate the properties of the pyrolysis oil and gas product, respectively. When pyrolysis was conducted without ZSM-5, the main components in the oil product were alkanes and alkenes, and the gas product was composed of short-chain hydrocarbons with little H₂. The addition of ZSM-5 significantly increased the aromatics yield (88.4%) in the oil product. Meanwhile, the content of H₂ and short-chain hydrocarbons increased as well. The effects of temperature on the catalytic effects of ZSM-5 were studied under 400-550℃. The results showed that 65.6% of oil can be recovered at 500℃ and the aromatics yield reached up to 90.9%. Moreover, the contents of resins and asphaltenes in the oil products were relatively low at this temperature. It can be deduced that the optimum catalytic temperature with ZSM-5 in this study was 500℃. The coke deposited on the catalyst was detected by thermogravimetric and X-ray photoelectron spectroscopy analysis. It was found that the main type of coke was polyaromatics coke due to the polycondensation reaction over ZSM-5.