Two acidic carbon materials （H-PRC and HS-C） were used as catalysts for the condensation reaction of methanol with formaldehyde to produce dimethoxymethane （DMM） in aqueous solution （hydrophilic system） and for ...Two acidic carbon materials （H-PRC and HS-C） were used as catalysts for the condensation reaction of methanol with formaldehyde to produce dimethoxymethane （DMM） in aqueous solution （hydrophilic system） and for the etherification of isopentene with methanol to produce tert amyl methyl ether （TAME） in toluene solution （lipophilic system）. Microcalorimetric adsorptions of water and benzene showed that the HS-C was highly hydrophilic without the lipophilicity, while the H-PRC exhibited both the hydrophilicity and lipophilicity. Thus, the HS-C was well dispersed in aqueous solution and difficult to separate from it. On the other hand, the H-PRC was highly active, more active than the acidic resin （D008） and sulfuric acid, for the synthesis of DMM in aqueous solution. The H-PRC was also highly active, more active than the HS-C, for the etherification of isopentene with methanol to produce TAME in toluene solution, probably owing to its amphiphilic surface property as well as its strong surface acidity as measured by the microcalorirnetric adsorption of NH3.展开更多
A mechanochemical method was employed to prepare modified iron molybdate catalysts with various metal salts as precursors.The physicochemical properties of the iron molybdate catalysts were characterized,and their per...A mechanochemical method was employed to prepare modified iron molybdate catalysts with various metal salts as precursors.The physicochemical properties of the iron molybdate catalysts were characterized,and their performances in catalyzing the reaction from methanol to formaldehyde(HCHO)were evaluated.Iron molybdate catalysts doped with Co(NO_(3))_(2)·6H_(2)Oand Al(NO_(3))_(3)·9H_(2)O resulted in high HCHO yields.Compared with a commercial catalyst,the HCHO yields in the reaction with the modified catalyst at an optimal Co/Mo molar ratio reached 97.37%.According to chemical state analysis,the formation of CoO and the efficient decrease in the MoO_(3)sublimation rate could be important factors enhancing the HCHO yield in reactions catalyzed with iron molybdate doped with different Co/Mo mole ratios.展开更多
文摘Two acidic carbon materials （H-PRC and HS-C） were used as catalysts for the condensation reaction of methanol with formaldehyde to produce dimethoxymethane （DMM） in aqueous solution （hydrophilic system） and for the etherification of isopentene with methanol to produce tert amyl methyl ether （TAME） in toluene solution （lipophilic system）. Microcalorimetric adsorptions of water and benzene showed that the HS-C was highly hydrophilic without the lipophilicity, while the H-PRC exhibited both the hydrophilicity and lipophilicity. Thus, the HS-C was well dispersed in aqueous solution and difficult to separate from it. On the other hand, the H-PRC was highly active, more active than the acidic resin （D008） and sulfuric acid, for the synthesis of DMM in aqueous solution. The H-PRC was also highly active, more active than the HS-C, for the etherification of isopentene with methanol to produce TAME in toluene solution, probably owing to its amphiphilic surface property as well as its strong surface acidity as measured by the microcalorirnetric adsorption of NH3.
基金the Natural Science Foundation Project of Xinjiang Uygur Autonomous(Grant No.2019D01C084)for financial support.
文摘A mechanochemical method was employed to prepare modified iron molybdate catalysts with various metal salts as precursors.The physicochemical properties of the iron molybdate catalysts were characterized,and their performances in catalyzing the reaction from methanol to formaldehyde(HCHO)were evaluated.Iron molybdate catalysts doped with Co(NO_(3))_(2)·6H_(2)Oand Al(NO_(3))_(3)·9H_(2)O resulted in high HCHO yields.Compared with a commercial catalyst,the HCHO yields in the reaction with the modified catalyst at an optimal Co/Mo molar ratio reached 97.37%.According to chemical state analysis,the formation of CoO and the efficient decrease in the MoO_(3)sublimation rate could be important factors enhancing the HCHO yield in reactions catalyzed with iron molybdate doped with different Co/Mo mole ratios.
