稀土助剂对Zn—Cr氧化物催化剂上低碳醇合成的影响

Effect of rare earth oxide promoters on higher alcohols synthesis over Zn-Cr oxide catalyst

用共沉淀法制备了5种ZnCrREK氧化物催化剂,10MPa、360～420℃、5000h^(-1)反应条件下,低碳醇合成反应结果表明,REO助剂能提高合成气转化率和催化剂生成醇活性,对甲烷化可能有抑制作用,其中Dy_2O_3、Tb_4O_7、Pr_6O_(11)能促进链增长,提高异丁醇收率,在一定浓度范围内,以Dy_2O_3效果最佳。

Zn-Cr oxide catalysts promoted with rare earth oxide (REO) were prepared by a coprecipitation procedure and the effects of REO (Nd_2O_3, LaCeO, Pr_6O_(11), Tb_4O_7 Dy_2O_3) promoters on higher alcohols synthesis were investigated. The results indicate that the introduction of RE leads to the enhancement of syngas conversion and possible suppression of methanation, which are favourable to the increase of activity for alcohols. Moreover, the introduction of Dy_2O_3,Tb_4O_7,Pr_6O_(11) can promote the chain growth and raise STY of i-butanol in varying degrees, and within a certain Dy concentration, Dy_2O_3 acts best among them.