摘要
研究了气相环氧丙烷（PO）异构化制烯丙醇反应中碱性Li3PO4催化剂的失活及再生.实验结果表明,在280℃下反应54 h后,因催化剂表面覆盖大量含氢碳物种引起失活,采用煅烧法、水蒸气洗涤法去除催化剂上的积碳,可使催化剂得到再生.通过XRD、FTIR、原位DRIFT、BET、TG、MAS NMR等手段对催化剂进行表征发现,失活Li3PO4催化剂的比表面及孔体积均下降,但催化剂晶型未发生改变,也无新物相生成.积碳分解温度为300～500℃,在350℃下积碳分解所需时间为40～ 50 min.煅烧法再生的Li3PO4催化剂上PO转化率为90.7％,烯丙醇选择性为89.8％,与新鲜Li3PO4催化剂的活性相近.
The deactivation and regeneration of basic lithium phosphate catalyst used in the isomeri- zation of propylene oxide to allyl alcohol were studied. The results showed that the basic lithium phosphate catalyst deactivated after the reaction at 280℃ for 54 h, which was due to carbon deposition con- taining H element. The carbon deposition could be removed by washing with steam or calcining. The fresh, deactivated and regenerated catalysts were characterized by means of XRD, FTIR, in-situ DRIFT, BET, TG and MAS NMR. The specific surface area and pore volume of the deactivated catalyst decreased without the formation of new phase. The decomposition temperature of the carbon deposition was in the range of 300 - 500℃ and, at 350℃ the decomposition needed 40 - 50 min. The conversion of propylene oxide and the selectivity to allyl alcohol on the catalyst regenerated by the cal- cining reached 90.7 % and 89.8 %, respectively, similar to those on the fresh catalyst.
出处
《石油化工》
CAS
CSCD
北大核心
2015年第4期453-458,共6页
Petrochemical Technology
基金
国家自然科学基金项目(21276127
51106076)
关键词
环氧丙烷
异构化
烯丙醇
磷酸锂催化剂
积碳
失活
再生
propylene oxide
isomerization
allyl alcohol
lithium phosphate catalyst
carbon deposition
deactivation
regeneration
