烷基苯生产中β沸石催化剂的失活和再生机理

MECHANISMS OF DEACTIVATION AND REGENERATION OF BETA ZEOLITE CATALYST IN PRODUCTION OF LINEAR ALKYLBENZENES

研究了用于直链烷基苯生产的β沸石催化剂的失活机理和再生机理。结果表明,β沸石的失活是由于生成的直链烷基苯本身逐渐堵塞孔道导致反应物分子不能接近活性中心引起的。热苯洗涤对失活催化剂进行再生时,伴随着堵塞孔道的直链烷基苯的向外扩散,有裂解、环化等反应发生,并形成了低碳芳烃、萘和茚、联苯、稠环芳烃、不饱和物等新物种。

The mechanisms of the deactivation and regeneration of beta zeolite catalyst in production of linear alkybenzenes were investigated. It was revealed that the deactivation of the catalyst was caused by the product linear alkylbenzenes, which gradually blocked the zeohte channels and prevented the accession of reactants toward the active sites. When the deactivated catalyst were regenerated by hot benzene washing, accompanied with alkybenzenes diffused from the pores, cracking and cyclization occun'ed and some new species, such as Iow-carbon aromatics, naphthalene, indane, biphenyl, condensed aromatics and some unsaturated compounds were formed.