Ni改性Cu/Mn/ZrO_2 催化剂上合成低碳混合醇的研究

Synthesis of Mixed Higher Alcohols by CO hydrogenation over Ni-Modified Cu/Mn/ZrO_2 Catalyst

Ni改性的Cu/Mn/ZrO2 是CO加氢合成低碳混合醇的有效催化剂 ,在较为温和的条件 (T =573K ,p =8 0MPa ,GHSV =50 0 0h- 1 )下 ,醇的时空产率为 0 36g/(ml·h) ,其中C2 +OH的选择性约 30 % .产物由直链C2 +OH和以异丁醇为主的支链醇构成 .温度和压力的提高明显促进了异丁醇的生成 .可以认为 ,Ni的添加对直链醇的生成有决定性作用 ,而异丁醇的生成取决于Zr的作用 .反应过程中甲烷等副产物的生成及水煤气变换反应可控制在合理的范围内 .另外 ,K助剂的加入可进一步促进C2 +OH的生成 .

Cu/Mn/ZrO 2 was prepared by coprecipitation method, and CO hydrogenation was performed in a fixed bed reactor to test the behavior of Ni modified Cu/Mn/ZrO 2 catalyst during the reaction. It was shown that the catalyst was an active one for methanol synthesis. When Ni was added as a promoter, CO hydrogenation products over the catalyst exhibited an obvious change from methanol to C 2+ OH. The alcohol yield of 0 36 g/(ml·h) with a C 2+ OH selectivity of about 30% was obtained under the condition of GHSV= 5?000 h -1 , p =8 0 MPa and T =573 K. The obtained product was a mixture of straight chain alcohols and branched alcohols (mainly i butanol), while the carbon number distribution of linear alcohol species followed the Schulz Flory equation very well. The formation of i butanol was thought to be determined by ZrO 2. The formation of branched alcohols greatly increased with the temperature. The effects of the operating variables was also studied.