In order to lay a foundation for effective regeneration of P W heteropoly acid catalyst supported on SiO 2 aged in the alkylation of isobutane with butene, the molecular structure and physicochemical properties of cok...In order to lay a foundation for effective regeneration of P W heteropoly acid catalyst supported on SiO 2 aged in the alkylation of isobutane with butene, the molecular structure and physicochemical properties of coke precursor deposited on the surface of solid acid alkylation catalyst are clearly recognized and identified by means of various characterization approaches, including IR, NMR, GC MS and GC. According to the characterization results, the coke precursors are mainly made up of long chain saturated hydrocarbons and small amount of polynucleo aromatics. The coke precursors deposit on the catalysts do not block the pores of the catalysts, but deposited on the acid centres of catalyst. It causes that the acid strength of active centres of the catalyst descends, and selectivity for alkylation becomes worse. It is found that the species of coke precursor consist of C 13 ～C 21 paraffin. The results obtained in the project are different entirely from that other researchers gained before. It will be of benefit to investigate and find out new regeneration methods of solid acid alkylation catalyst.展开更多
Tungstophosphoric acid pillar double hydroxides with composition of M2Al-PW12[M=Zn2+,Co2+,Ni2+,Mg2+] have been synthesized and their catalytic activities for isobutane-butene alkylation were studied. The results showe...Tungstophosphoric acid pillar double hydroxides with composition of M2Al-PW12[M=Zn2+,Co2+,Ni2+,Mg2+] have been synthesized and their catalytic activities for isobutane-butene alkylation were studied. The results showed that M2Al-PW12 had higher initial activity and selectivity of product, but lower deactivation rate than parent H3PW12and the activity of the catalysts and selectivity in alkylation appeared in relation with the kinds of elements in double hydroxide.展开更多
分别在液相和超临界两种反应条件下进行了固体酸烷基化催化剂的烷基化反应,并以超临界异丁烷流体对失活催化剂进行了再生。考察了流体相态、再生温度、压力、物料空速和时间对再生效果的影响。结果表明,对于液相反应24 h 的催化剂,在18...分别在液相和超临界两种反应条件下进行了固体酸烷基化催化剂的烷基化反应,并以超临界异丁烷流体对失活催化剂进行了再生。考察了流体相态、再生温度、压力、物料空速和时间对再生效果的影响。结果表明,对于液相反应24 h 的催化剂,在180℃条件下经超临界异丁烷流体再生,反应转化率由90%恢复至100%;C_8烷烃选择性由40%恢复至69.13%,达到新鲜剂的92.8%。对于超临界反应36 h 的催化剂,再生后 C_8烷烃选择性可恢复至新鲜剂的82.4%;200℃再生后,碳含量由4.55%降至1.79%,脱除率为60.7%。展开更多
文摘In order to lay a foundation for effective regeneration of P W heteropoly acid catalyst supported on SiO 2 aged in the alkylation of isobutane with butene, the molecular structure and physicochemical properties of coke precursor deposited on the surface of solid acid alkylation catalyst are clearly recognized and identified by means of various characterization approaches, including IR, NMR, GC MS and GC. According to the characterization results, the coke precursors are mainly made up of long chain saturated hydrocarbons and small amount of polynucleo aromatics. The coke precursors deposit on the catalysts do not block the pores of the catalysts, but deposited on the acid centres of catalyst. It causes that the acid strength of active centres of the catalyst descends, and selectivity for alkylation becomes worse. It is found that the species of coke precursor consist of C 13 ～C 21 paraffin. The results obtained in the project are different entirely from that other researchers gained before. It will be of benefit to investigate and find out new regeneration methods of solid acid alkylation catalyst.
文摘Tungstophosphoric acid pillar double hydroxides with composition of M2Al-PW12[M=Zn2+,Co2+,Ni2+,Mg2+] have been synthesized and their catalytic activities for isobutane-butene alkylation were studied. The results showed that M2Al-PW12 had higher initial activity and selectivity of product, but lower deactivation rate than parent H3PW12and the activity of the catalysts and selectivity in alkylation appeared in relation with the kinds of elements in double hydroxide.
文摘分别在液相和超临界两种反应条件下进行了固体酸烷基化催化剂的烷基化反应,并以超临界异丁烷流体对失活催化剂进行了再生。考察了流体相态、再生温度、压力、物料空速和时间对再生效果的影响。结果表明,对于液相反应24 h 的催化剂,在180℃条件下经超临界异丁烷流体再生,反应转化率由90%恢复至100%;C_8烷烃选择性由40%恢复至69.13%,达到新鲜剂的92.8%。对于超临界反应36 h 的催化剂,再生后 C_8烷烃选择性可恢复至新鲜剂的82.4%;200℃再生后,碳含量由4.55%降至1.79%,脱除率为60.7%。
