廉价铁基催化剂Ｆ-Ｔ合成反应性能初探

以四个廉价的FeSO4工业原料为铁源,采用连续共沉淀法制得含铁浆料,再用喷雾干燥法制得微米级球状Fe-Cu-Ｋ-SiO2催化剂。在Ｈ2/ＣＯ=2、526Ｋ、2 0MPa、2000ｈ-1条件下于固定床反应器上考察了这四个铁基催化剂的Ｆ-Ｔ合成反应活性、选择性和稳定性,结果表明在240ｈ运行时间内,该四个催化剂均表现出良好的反应活性和选择性,而稳定性则有不同程度的下降,其中2#催化剂性能相对较优,初始ＣＯ转化率为77.89%,经历反应诱导期40ｈ时达到89 58%,其后ＣＯ转化率逐渐下降,失活速率为1 33%/ｄ;在整个运行期间ＣＨ4选择性维持在4%左右,Ｃ+5选择性在80%左右。

A PRELIMINARY STUDY ON PERFORMANCE OF INEXPENSIVE IRON-BASED CATALYSTS FOR FISCHER-TROPSCH SYNTHESIS

The micrometer scale spherical Fe-Cu-K-SiO2 catalysts were prepared by means of spray drying technology for precipitate slurry, which was obtained by a continuous precipitation method using four inexpensive industrial by products, FeSO4 as raw material. The reactivity, selectivity and stability of four catalysts for Fischer-Tropsch synthesis were tested in a fixed-bed reactor at 526 K, 2.0 MPa and gas hourly space velocity of 2 000 h－1 with syngas of H2/CO=2 during the period of 240 h. The results indicated that four catalysts showed higher CO conversion and C5+ product selectivity, the CO conversion gradually decreased with differentrates. In terms of the CO conversion and stability, catalyst 2# was the best among the catalysts studied. Its initial CO conversion was 77.89%, and passed through a maximum of 89.58% after an inductive period for about 40 hour, and then gradually decreased with a deactivation rate of 1.33%/d. The selectivity of CH4 and C5+ kept about 4% and 80%, respectively, in the whole run period for catalyst 2#.