.co / Co <sub> 2 </ Sub> Total Hydrogenated Synthetic Methanol Copper-based Catalyst Modified Research

Synthesis methanol from CO and CO2hydrogenation can not only improve the condition of environment, but also realize the effective utilization of resources. In this paper, methanol synthesis from CO and CO2hydrogenation over industrial catalysts CZA301and CZA207and its catalytic performance were investigated and compared. Methanol synthesis from CO and CO2co-hydrogenation over catalysts CZA301and CZA301-Zr2%based on modified CZA301catalyst were also investigated. A further study on methanol synthesis from CO and CO2co-hydrogenation over copper-based catalysts, modified copper-based catalysts and doped modifiers of different content was conducted. Catalytic properties of the catalysts were systemically investigated, using the technologies of X-ray diffraction(XRD), hydrogen temperature programmed reduction(H2-TPR), carbon dioxide temperature programmed desorption(CO2-TPD), nitrogen adsorption-desorption(BET), activity evaluation was conducted in a micro fixed-bed reactor. After analysis, some important results and conclusions were as follows.(1) The catalytic properties of industrial catalyst CZA301was better than CZA207, and the industrial methanol synthesis catalyst CZA301doped CeO2, ZrO2, La2O3, MnO2, Pr2O3, SrO,V2O5by impregnating, the result showed that the ZrO2-doped CZA301has enthanced CO2conversion by about5percentage points, methanol selectivity by about8percentage points.(2) By the study on modification of catalyst CZA301with different contents of ZrO2, it was found that the conversion of CO, CO2was increased and the yields of methanol were21.26%and17.13%when the contents of ZrO2was2.0%and1.5%, respectively. Compared CZA301with CZA301-Zr2%catalyst for methanol synthesis from CO and CO2co-hydrogenation, the results showed that yield of methanol from CO and CO2co-hydrogenation was larger than CO or CO2hydrogenation under the same reaction conditions.(3) Various mole compositions of Cu/Zn/Al catalysts were prepared by concurrent coprecipitation. Compared the catalytic properties of CO and CO2co-hydrogenation to methanol, the results showed that catalyst behaved better catalytic performance when the mole ratio of Cu/Zn/Al was6.0/3.2/0.8, and the yield of methanol was28.04%, the conversion of CO and the conversion of CO2reached to56.47%and20.12%respectively.(4) A series of modified copper-based catalysts with different promoters included ZrO2, SiO2, MgO, CaO, Fe2O3, K2O were prepared by parallel co-precipitation method or incipient wet impregnation method, the results showed that the catalyst which was modified by ZrO2, MgO, CaO promoters promoted the activation of methanol synthesis by CO and CO2co-hydrogenation. Compared to the CZA catalyst, CZAZr catalyst showed higher conversion of total carbon, and CZAMg catalyst showed higher methanol selectivity.(5) By the study on the catalytic properties of catalysts with different modified promoters and contents for methanol synthesis from CO and CO2co-hydrgenation, the results showed that when the modified mol contents4%ZrO2and2%MgO were both adjusted for Cu/Zn/Al catalyst, the yield of methanol was up to31.43%and28.16%respectively, and0.6%content(mass fraction) ZrO2MgO was adjusted for Cu/Zn/Al catalyst, the conversion of total carbon was42.07%, the yield of methanol was33.0%.Based on the above study, it can be concluded that the CZAZrMg0.6%catalyst has better catalytic activity to the methanol synthesis from CO and CO2co-hydrogenation, the best composition of (CuZnAl):(ZrMg) was99.4%:0.6%(mass ratio), Cu:Zn:Al was6.0:3.2:0.8(mol ratio), Zr:Mg was2:1(mol ratio), and in this case, the conversion of CO and the conversion of CO2were56.45%and28.75%, respectively, the selectivity of methanol was78.43%.