SSZ-13和 SAPO-34对乙醇脱水制乙烯反应的对比研究

摘要

SSZ-13 catalyst was synthetised with N, N, N -trimethyl alkyl ammonium hydroxide as template. SAPO -34 molecular sieve was synthetised with triethylamine (TEA) . The the catalysts were characterized by XRD, SEM, low-temperature N2 adsorption. Then studied the catalytic properties of ethanol dehydration reactions at different conditions for the catalyst prepared in a fixed bed reactor were studied. The results indicate that the prepared SSZ-13 molecular sieve belongs to chabazite structure, in the process of ethanol dehydration to ethylene, the average conversion of ethanol and average selectivity of ethylene is 98.8% and 99.2% at 350 ℃ . In the same conditions, the average conversion of ethanol and average selectivity of ethylene is 78.2% and 53.5% when using SAPO-34 molecular sieve as a catalyst of ethanol dehydration to ethylene.%以 N，N，N-三甲基-1-金刚烷基氢氧化铵为模板剂合成了 SSZ-13分子筛催化剂，并以三乙胺（TEA）为模板剂合成了 SAPO-34分子筛催化剂.采用 X 射线衍射、扫描电镜、低温氮吸附等方法对催化剂进行了表征.在固定床反应器中考察了这2种催化剂在不同条件下对乙醇脱水反应的催化活性.结果表明：所制备的 SSZ-13分子筛具有典型的 CHA 型结构，当反应温度为350℃时，乙醇平均转化率和乙烯平均选择性分别为98.8%和99.2%，而在相同条件下，以 SAPO-34为催化剂时乙醇平均转化率和乙烯平均选择性分别仅为78.2%和53.5%.