Modulating C5+selectivity for Fischer-Tropsch synthesis by tuning pyrolysis temperature of MOFs derived Fe-based catalyst

Effect of Pyrolysis Conditions on the MOFs-Derived Zinc-Based Catalysts in Acetylene Acetoxylation

The preparation method and calcination temperature of metal-organic framework (MOFs)-derived materials are critical factors affecting catalytic performance. In this work, the preparation conditions of MOFS precursors were optimized, and zinc-based catalysts with different activities (MOF5-700, MOF5-750, and MOF5-800) were obtained by pyrolysis of MOFS precursors under nitrogen, which were then applied to an acetylene acetoxylation reaction system. According to the results, the conversion rate of acetic acid under catalysis was significantly different. (MOF5-700 (48%), MOF5-750 (62%), and MOF5-800 (22%)). Comparing the activity of the catalyst with the industrial catalyst Zn(OAc)2/AC (20%), MOF5-750 showed higher activity, and the acetic acid conversion rate remained around 60% after 50 h of stability testing. By characterization analysis, MOFs-derived materials were obtained after proper temperature pyrolysis. They have high mesoporous content, defects, and oxygen-containing functional groups and can maintain a good crystal structure, greatly reducing the loss of active components. This is the main reason for the good performance of the MOF5-750 catalyst in acetylene acetoxylation. Thus, the preparation conditions and favorable pyrolysis temperature of MOF derivative catalysts play a key role in the catalytic performance of acetylene acetoxylation.

A novel carbonized derivative of Fe-Cu bimetallic organic framework (Fe-Cu-MOF@C): preparation and optimization

A carbon derivative with Fe-Cu bimetallic organic framework (Fe-Cu-MOF@C) was prepared by microwave synthesis and pyrolysis. Using potassium persulfate (PS) as oxidant and 2,4-dichlorophenol (2,4-DCP) as target pollutant, the optimal preparation conditions of Fe-Cu-MOF@C were studied. The factors affecting the synthesis of Fe-Cu-MOF include microwave power, microwave time, microwave temperature, the molar ratio of metal ions to organic ligands, the molar ratio of iron and copper, etc. In addition, the influence of pyrolysis temperature on the performance of Fe-Cu-MOF@C cannot be ignored. The results show that Fe-Cu-MOF@C has the best catalytic performance when the microwave time is 30 min, the microwave power is 600 W, the microwave temperature is 150 °C, the molar ratio of (Fe²⁺ + Cu²⁺)/H₂BDC is 10:3, the molar ratio of Fe²⁺/Cu²⁺ is 10:1, and the pyrolysis temperature is 700 °C. After 90 min of reaction, 2,4-DCP was completely removed. Repeatable experiments show that Fe-Cu-MOF@C has good stability and its service life can be restored by heat treatment. In this study, a heterogeneous catalyst with strong catalytic capacity, high stability and easy recovery was prepared by a simple and efficient process, which is conducive to the development of advanced oxidation technology and the progress of water environmental protection.