以Ce-SBA-15为载体,硝酸镁为活性组分前驱体,通过浸渍法制备了Mg/Ce-SBA-15催化剂.利用XRD、N2吸附-脱附、SEM、EDS、NH3-TPD、Py-FTIR和TG-DTA手段对催化剂进行表征.结果表明,Mg掺杂并未破坏载体结构,催化剂表面弱酸含量有所增加,L酸增加明显.在固定床反应器中评价了Mg/Ce-SBA-15分子筛催化苯酚甲醇烷基化的反应性能.结果表明,Mg负载量为7%、焙烧温度为550℃、焙烧时间为4.5h制备的Mg/Ce-SBA-15催化剂催化效果最佳.在反应温度460℃,n(苯酚):n(甲醇)为1:4,质量空速为3.0h-1,常压的条件下,苯酚转化率为80.1%,邻甲酚选择性为86.4%.%Mg/Ce-SBA-15 mesoporous molecular sieves were synthesized by using Ce-SBA-15 as support and magnesium nitrate as precursor through impregnation method.The samples were characterized by XRD,N2 adsorption-desorption,BET,SEM,NH3-TPD,Py-FTIR and TG-DTA techniques.The results indicate that the original crystal structures of SBA-15 remain unchanged after modification with Mg,but the number of weak acids were increased especially L acids.The performances of catalysts in phenol alkylation with methanol were studied in a fixed bed reactor.The results showed that the catalyst showed the highest catalytic activity under the conditions of Mg content =7%,calcination temperature =550℃ and calcination time =4.5h.At 460℃,n(phenol):n(methanol) =1:4,WHSV =3.0h-1 and atmospheric pressure,the conversion of phenol was 80.1% and the selectivity to o-cresol was 86.4%.
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