By using the platinum group metals rhodium and indium as main component and α-Al2O3 as carrier to make bimetallic heterogeneous catalyst, the optimal catalyst preparation conditions and the catalytic effect were investigated. The rhodium nitrate and indium nitrate were used as catalyst precursor. Rhodium was impregnated and calcinated firstly, and then indium. A group of catalysts with different Rh and Ir mass fractions were prepared. The mass fraction of the metals in catalyst support was characterized by ICP-AES method. The experimental results show that Rh-Ir bimetallic heterogeneous catalyst with high activity and stability can be prepared when the mass fraction of Rh and Ir is 0.5% and 0.3% , respectively, calcination temperature is 450 ℃ for Rh and 550℃ for Ir, and calcinations time is 2 h. The new bimetallic catalysts were investigated in an autoclave to produce acetic acid. The space-time yield of acetic acid (STY) is near 18 mol/(L ? H), the methanol conversion is 60.1% and the selectivity of acetic acid is 99.2 % under the optimum reaction conditions of reaction temperature 180℃, reaction pressure 4.0 Mpa, reaction time 30 min, n(MeOH) :n(AcOH) :n(MeOAC) :n(MeI) =1:1:0.3:0.2, total volume 200 mL.%采用贵金属铑和铱作为催化剂主成分,以α形态的三氧化二铝为载体,组成双金属非均相催化剂,考察该催化剂的最佳制备条件及催化效果.选用硝酸铑和硝酸铱分别作为铑和铱的前躯体,采用先浸渍焙烧铑再浸渍焙烧铱的制备方法,分别制备了不同铑铱质量分数的双金属催化剂,催化剂中的金属质量分数通过ICP-AES法来测定.该双金属催化剂在450℃焙烧铑和550℃焙烧铱,各2h的焙烧条件下,铑铱质量分数分别为0.5％铑-0.3％铱下制得高活性高稳定的铑-铱双金属非均相催化剂.该催化剂在反应温度180℃,反应压力4.0 MPa,反应时间30 min,反应液摩尔比n(MeOH)∶n(AcOH)∶n(MeOAC)∶n(MeI)=1∶1∶0.3∶0.2,总体积200mL的条件下,醋酸的时空收率为18 mol/(L·h),产物以甲醇计其转化率为60.1％,醋酸的选择性为99.2％.
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