氨肟化工艺失活HTS分子筛酸性质对其催化氧化性能的影响  

Effect of Acidity of Industrial Deactivated HTS Zeolite on Its Catalytic Oxidation Performance

作　　者：夏长久[1] 郑爱国[1] 朱斌[1] 向彦娟[1] 忻睦迪[1] 林民[1] 徐广通[1] 舒兴田[1] 

机构地区：[1]中国石化石油化工科学研究院石油化工催化材料与反应工程国家重点实验室,北京100083

出　　处：《石油学报（石油加工）》2014年第5期779-784,共6页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家重点基础研究发展计划"973"项目(2006CB202500.7-22)基金资助

摘　　要：采用NH3-TPD和吸附吡啶红外光谱对工业失活HTS分子筛的酸性质进行了表征,并采用苯酚羟基化活性评价和H2O2分解实验结果探析HTS分子筛的失活原因。结果表明,失活HTS分子筛中出现大量Brnsted酸,且Lewis酸量显著增加,呈现出弱酸、中强酸和强酸3种强度分布。根据田部浩三规则分析,可以确定Brnsted和Lewis酸来源于失活HTS分子筛颗粒表面的无定型TiO2-SiO2二元氧化物团簇。骨架四配位Ti物种催化氧化有机物的反应与无定型含Ti团簇催化H2O2分解反应互为竞争反应,骨架Ti含量下降和无定型含Ti物种增加是引起HTS分子筛失活的主要原因。The acid characteristics of deactivated HTS zeolite were investigated by NH3-TPD and Py-IR spectrum.The phenol hydroxylation and H2O2 decomposition catalyzed by fresh and deactivated HTS zeolites and Anatase TiO2 crystal were carried out to analyze the deactivation reason of HTS zeolite.It was found that there were amount of Brnsted and Lewis acid sites in deactivated HTS zeolite,containing weak acid,mediate strong acid and strong acid.According to the Tanabe hypothesis regarding the surface acidity,these types of Brnsted and Lewis acid were originated from the amorphous TiO2-SiO2 binary oxides clusters in the surface of deactivated HTS zeolite,which was attributed to the H2O2 decomposition.There was a competitive relationship between the catalytic oxidation and the decomposition of oxidant,and the real deactivation reason of HTS zeolite was the decrease of its tetrahedral framework Ti species and the increase of amorphous TiO2-SiO2 binary clusters causing H2O2 decomposition.

关 键 词：空心钛硅分子筛 氨肟化 NH3-TPD 吡啶吸附红外光谱 酸性 失活 

分 类 号：TQ426[化学工程]