Conversion of industrial solid wastes into functional materials has attracted considerable interest,as it can reduce environmental pollution and facilitate the sustainable development of relevant processes.Herein,spen...Conversion of industrial solid wastes into functional materials has attracted considerable interest,as it can reduce environmental pollution and facilitate the sustainable development of relevant processes.Herein,spent methanol-to-olefins(MTO)industrial catalyst was explored for the synthesis of DNL-6 molecular sieve,a promising SAPO-type adsorbent for CO_(2) capture.It was demonstrated that DNL-6 with high purity and crystallinity,and various silica contents can be readily synthesized.Na-exchanged DNL-6 was further prepared using the as-synthesized DNL-6 as the precursor,and its structure was investigated by Rietveld refinement,revealing that Na cations were mainly located in the single 8-rings(S8Rs).Na-DNL-6 with varied silica contents and Na contents were investigated for adsorption studies.Na-DNL-6 with a high Na exchange degree exhibited comparable CO_(2) uptake with H-DNL-6(298 K and 101 kPa);but superior separation selectivity for CO_(2)/CH4(as high as 1369,50/50 kPa);CO_(2)/N_(2)(∞,15/85 kPa)owing to the“trapdoor”effect associated with the Na cations sited in the S8Rs.This work provides an eco-friendly approach for the synthesis of efficient silicoaluminophosphate adsorbent for CO_(2) capture.展开更多
PASCA, ESR and Microreactor, have been used to study the states and properties of coking deposits on catalyst. The results indicate that the C exists as three types of states on catalyst surface. The first and second ...PASCA, ESR and Microreactor, have been used to study the states and properties of coking deposits on catalyst. The results indicate that the C exists as three types of states on catalyst surface. The first and second types of carbon are the main reason of the catalyst deactivation, but the third type has a promoting role in n-C_7 hydrocracking reaction. The S_s-C interacts strongly with catalyst, forming metal-carbon-support interaction (MCSI).展开更多
A fundamental step in the production of an industrial catalyst is its crushing strength assessment. Limited literature exists in which the strength reliability of supported catalysts is investigated from production to...A fundamental step in the production of an industrial catalyst is its crushing strength assessment. Limited literature exists in which the strength reliability of supported catalysts is investigated from production to their application in a reactor. In this work, cylindrical supports were prepared by pelletizing high poros- ity γ-alumina powder, and Cu-Znf/γ-Al2O3 catalysts were prepared by impregnation of the pelletized γ-alumina supports with an aqueous solution of copper and zinc nitrates. The support-forming variables, such as binder concentration, compaction pressure, calcination temperature, and drying procedure were investigated. The Weibull method was used to analyze the crushing strength data of the supports, and the fresh and used catalysts before and after the low-temperature water gas shift reaction. Support formation at a 50 wt% binder concentration, 1148 MPa compaction pressure, 500 ℃ calcination temperature, and rapid drying （100 ℃, 8 h） led to the maximum support mechanical reliability. The most reliable catalyst with respect to simultaneous appropriate catalytic performance and mechanical strength was prepared from a support with the lowest mean crushing strength （26.25 MPa）. This work illustrates the impor- tance of the Weibull modulus as a useful mechanical reliability index in manufacturing a supported solid catalyst.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21991090,21991091,22171259,22272173)the AI S&T Program of Yulin Branch,Dalian National Laboratory for Clean Energy,CAS(No.DNL-YL A202206)The authors thank to the funding from the Sino-French IRN(International Research Network).
文摘Conversion of industrial solid wastes into functional materials has attracted considerable interest,as it can reduce environmental pollution and facilitate the sustainable development of relevant processes.Herein,spent methanol-to-olefins(MTO)industrial catalyst was explored for the synthesis of DNL-6 molecular sieve,a promising SAPO-type adsorbent for CO_(2) capture.It was demonstrated that DNL-6 with high purity and crystallinity,and various silica contents can be readily synthesized.Na-exchanged DNL-6 was further prepared using the as-synthesized DNL-6 as the precursor,and its structure was investigated by Rietveld refinement,revealing that Na cations were mainly located in the single 8-rings(S8Rs).Na-DNL-6 with varied silica contents and Na contents were investigated for adsorption studies.Na-DNL-6 with a high Na exchange degree exhibited comparable CO_(2) uptake with H-DNL-6(298 K and 101 kPa);but superior separation selectivity for CO_(2)/CH4(as high as 1369,50/50 kPa);CO_(2)/N_(2)(∞,15/85 kPa)owing to the“trapdoor”effect associated with the Na cations sited in the S8Rs.This work provides an eco-friendly approach for the synthesis of efficient silicoaluminophosphate adsorbent for CO_(2) capture.
文摘PASCA, ESR and Microreactor, have been used to study the states and properties of coking deposits on catalyst. The results indicate that the C exists as three types of states on catalyst surface. The first and second types of carbon are the main reason of the catalyst deactivation, but the third type has a promoting role in n-C_7 hydrocracking reaction. The S_s-C interacts strongly with catalyst, forming metal-carbon-support interaction (MCSI).
文摘A fundamental step in the production of an industrial catalyst is its crushing strength assessment. Limited literature exists in which the strength reliability of supported catalysts is investigated from production to their application in a reactor. In this work, cylindrical supports were prepared by pelletizing high poros- ity γ-alumina powder, and Cu-Znf/γ-Al2O3 catalysts were prepared by impregnation of the pelletized γ-alumina supports with an aqueous solution of copper and zinc nitrates. The support-forming variables, such as binder concentration, compaction pressure, calcination temperature, and drying procedure were investigated. The Weibull method was used to analyze the crushing strength data of the supports, and the fresh and used catalysts before and after the low-temperature water gas shift reaction. Support formation at a 50 wt% binder concentration, 1148 MPa compaction pressure, 500 ℃ calcination temperature, and rapid drying （100 ℃, 8 h） led to the maximum support mechanical reliability. The most reliable catalyst with respect to simultaneous appropriate catalytic performance and mechanical strength was prepared from a support with the lowest mean crushing strength （26.25 MPa）. This work illustrates the impor- tance of the Weibull modulus as a useful mechanical reliability index in manufacturing a supported solid catalyst.
