Titanium silicalite (TS-1) without and with extra-framework titanium have been prepared and TiO_2 is also prepared under the same conditions.All the samples are characterized with XRD,FT-IR,and UV–Vis.The effects of ...Titanium silicalite (TS-1) without and with extra-framework titanium have been prepared and TiO_2 is also prepared under the same conditions.All the samples are characterized with XRD,FT-IR,and UV–Vis.The effects of extra-framework titanium in TS-1 on the ammoximation of cyclohexanone have been studied in a continuous slurry reactor.The characterization results reveal that the extra-framework titanium exists as anatase.The catalytic evaluation results show that the anatase has a positive effect on the ammoximation of cyclohexanone by extending the catalytic life because it also exhibits some activity,while the conversion of cyclohexanone and the selectivity to cyclohexanone oxime are not influenced.The anatase TiO_2 does not catalyze H_2O_2 decomposition appreciably compared with TS-1 without extra-framework titanium.The results are very useful in guiding the TS-1 production.展开更多
基金was supported by the National Basic Research Program of China(‘‘973’’Program,No.G2000048005)the National Natural Science Foundation of China(No.21276183)
文摘Titanium silicalite (TS-1) without and with extra-framework titanium have been prepared and TiO_2 is also prepared under the same conditions.All the samples are characterized with XRD,FT-IR,and UV–Vis.The effects of extra-framework titanium in TS-1 on the ammoximation of cyclohexanone have been studied in a continuous slurry reactor.The characterization results reveal that the extra-framework titanium exists as anatase.The catalytic evaluation results show that the anatase has a positive effect on the ammoximation of cyclohexanone by extending the catalytic life because it also exhibits some activity,while the conversion of cyclohexanone and the selectivity to cyclohexanone oxime are not influenced.The anatase TiO_2 does not catalyze H_2O_2 decomposition appreciably compared with TS-1 without extra-framework titanium.The results are very useful in guiding the TS-1 production.