收集甲醇制烯烃(methanol to olefins,MTO)工业装置上产生的细粉类废催化剂作为原料,经高温焙烧和离子交换等手段预处理脱除催化剂表面积碳和碱金属,恢复部分活性位。将预处理后的废催化剂与一定量的固体硅源进行物理混合并在蒸汽相转移...收集甲醇制烯烃(methanol to olefins,MTO)工业装置上产生的细粉类废催化剂作为原料,经高温焙烧和离子交换等手段预处理脱除催化剂表面积碳和碱金属,恢复部分活性位。将预处理后的废催化剂与一定量的固体硅源进行物理混合并在蒸汽相转移(vapor-phase transport,VPT)条件下再次晶化5 h即可恢复全部活性。通过XRD,NH_(3)-TPD和BET等手段分析表明,VPT二次晶化后废催化剂的结晶度明显提高,强酸酸量和比表面积均达到新鲜催化剂的标准。将恢复活性的废催化剂与黏结剂在水中打浆,浆液经研磨分散后喷雾干燥成微球催化剂。MTO评价结果显示:100%的废催化剂成型剂(XJ-100)与100%的自制新鲜催化剂成型剂(XJ-0)相比,反应寿命延长了13.8%,双烯选择性提高了1%,但其磨耗较差,催化剂表面有明显的裂纹。最后,通过将废催化剂浆液与新鲜催化剂浆液按比例混合的喷雾成型方式,最终可得到物理性质和催化活性均满足工业应用的MTO催化剂。本研究提出的VPT法修复废催化剂活性和混合喷雾再生相结合的方式是一条绿色的废催化剂再生途径,也为蒸汽相转移法的工业化应用提供了一种新思路。展开更多
ZnO particles were prepared by Au-catalyzed vapor phase transport method on silicon substrate. Scanning electron microscopy（SEM） images show many ZnO particles were formed on the sample surface. They grew up layer b...ZnO particles were prepared by Au-catalyzed vapor phase transport method on silicon substrate. Scanning electron microscopy（SEM） images show many ZnO particles were formed on the sample surface. They grew up layer by layer along the c-axis, which was confirmed by the results of X-ray diffraction（XRD）. The morphology of ZnO particles is close to hemisphere and its formation process could be seen from the SEM image. The room temperature photoluminescence（PL） measurement revealed a narrow UV emission peak at 3.27 eV and a broad green emission peak at 2.45 eV, which was caused by the near-band-edge and deep-level emissions.展开更多
MnSAPO-34 molecular sieves were synthesized by vapor-phase transport （VPT） method using triethylamine （Et3N） as a structure directing agent （SDA）, and were characterized by XRD, BET, SEM, UV-Vis, FT-IR, and TG a...MnSAPO-34 molecular sieves were synthesized by vapor-phase transport （VPT） method using triethylamine （Et3N） as a structure directing agent （SDA）, and were characterized by XRD, BET, SEM, UV-Vis, FT-IR, and TG analy- ses. The influence of the zeolite crystallization conditions and the dry-gel composition were investigated. The results showed that the synthesis conditions had an effect on the crystalline phase. Pure MnSAPO-34 had been obtained when it was crystallized at 140 C for 18 hours. The ratio of MnO/A1203 in the starting gel ranging from 0.1 to 0.2 resulted in pure MnSAPO-34 with a CHA topology. Beyond this scope, MnSAPO-5 with an AFI topology structure was obtained as an impurity substance. UV-Vis spectroscopy and FT-IR spectroscopy study indicated that manganese was incorporated into the framework of the molecular sieve. The catalytic performance of MnSAPO-34 molecular sieve was tested by ketalization reaction of l, 2-propanediol with cyclohexanone. High yield of cyclohexanone-1, 2-propanediol ketal was obtained.展开更多
文摘收集甲醇制烯烃(methanol to olefins,MTO)工业装置上产生的细粉类废催化剂作为原料,经高温焙烧和离子交换等手段预处理脱除催化剂表面积碳和碱金属,恢复部分活性位。将预处理后的废催化剂与一定量的固体硅源进行物理混合并在蒸汽相转移(vapor-phase transport,VPT)条件下再次晶化5 h即可恢复全部活性。通过XRD,NH_(3)-TPD和BET等手段分析表明,VPT二次晶化后废催化剂的结晶度明显提高,强酸酸量和比表面积均达到新鲜催化剂的标准。将恢复活性的废催化剂与黏结剂在水中打浆,浆液经研磨分散后喷雾干燥成微球催化剂。MTO评价结果显示:100%的废催化剂成型剂(XJ-100)与100%的自制新鲜催化剂成型剂(XJ-0)相比,反应寿命延长了13.8%,双烯选择性提高了1%,但其磨耗较差,催化剂表面有明显的裂纹。最后,通过将废催化剂浆液与新鲜催化剂浆液按比例混合的喷雾成型方式,最终可得到物理性质和催化活性均满足工业应用的MTO催化剂。本研究提出的VPT法修复废催化剂活性和混合喷雾再生相结合的方式是一条绿色的废催化剂再生途径,也为蒸汽相转移法的工业化应用提供了一种新思路。
基金Supported by the National Natural Science Foundation of China(Nos.20631010 and 90922034)the Graduate Innovation Fund of "985" Program of Jilin University, China
文摘ZnO particles were prepared by Au-catalyzed vapor phase transport method on silicon substrate. Scanning electron microscopy（SEM） images show many ZnO particles were formed on the sample surface. They grew up layer by layer along the c-axis, which was confirmed by the results of X-ray diffraction（XRD）. The morphology of ZnO particles is close to hemisphere and its formation process could be seen from the SEM image. The room temperature photoluminescence（PL） measurement revealed a narrow UV emission peak at 3.27 eV and a broad green emission peak at 2.45 eV, which was caused by the near-band-edge and deep-level emissions.
基金supported by the Key Laboratory of Fine Chemicals,Jiangsu Provincefinancially supported by the Jiangsu Province Science and Technology Support Program (BE2011651)the Key University Science Research Project of Jiangsu Province (11KJA610002)
文摘MnSAPO-34 molecular sieves were synthesized by vapor-phase transport （VPT） method using triethylamine （Et3N） as a structure directing agent （SDA）, and were characterized by XRD, BET, SEM, UV-Vis, FT-IR, and TG analy- ses. The influence of the zeolite crystallization conditions and the dry-gel composition were investigated. The results showed that the synthesis conditions had an effect on the crystalline phase. Pure MnSAPO-34 had been obtained when it was crystallized at 140 C for 18 hours. The ratio of MnO/A1203 in the starting gel ranging from 0.1 to 0.2 resulted in pure MnSAPO-34 with a CHA topology. Beyond this scope, MnSAPO-5 with an AFI topology structure was obtained as an impurity substance. UV-Vis spectroscopy and FT-IR spectroscopy study indicated that manganese was incorporated into the framework of the molecular sieve. The catalytic performance of MnSAPO-34 molecular sieve was tested by ketalization reaction of l, 2-propanediol with cyclohexanone. High yield of cyclohexanone-1, 2-propanediol ketal was obtained.
