Reactivity of heteropolytungstate and heteropolymolybdate metal transition salts in the synthesis of dimethyl carbonate from methanol and CO₂.
A series of Keggin-type heteropoly compounds (HPC) having different countercations (Co, Fe) and different addenda atoms (W, Mo) were synthesized and characterized by means of Fourier-Transform Infrared Spectrometer (FT-IR) and X-ray powder diffraction (XRD). The catalytic properties of the prepared catalysts for the dimethyl carbonate (DMC) synthesis from CO(2) and CH(3)OH were investigated. The experimental results showed that the catalytic activity is significantly influenced by the type of the countercation and addenda atoms transition metal. Among the catalysts examined, Co(1.5)PW(12)O(40) is the most active for the DMC synthesis, owing to the synergetic effect between Co and W. Investigating the effect of the support showed that the least acidic one (Al(2)O(3)) enhanced the conversion but decreased the DMC selectivity in favor of that of methyl formate (MF), while that of dimethoxy methane remained stable.
Aouissi
Ahmed
A
Department of Chemistry, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia.
Al-Deyab
Salem S
SS
Al-Owais
Ahmad
A
Al-Amro
Amro
A
D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D005561:Formates / Q000138:chemical synthesis*; D008670:Metals / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry*; D012492:Salts / Q000737:chemistry*; D028561:Transition Elements
D005561:Formates; D008670:Metals; D012492:Salts; D028561:Transition Elements; D002245:Carbon Dioxide; C023025:methyl carbonate; D000432:Methanol