石油炼制与化工 ›› 2015, Vol. 46 ›› Issue (12): 25-30.

• 基础研究 • 上一篇    下一篇

液体介质对固定床钴基催化剂费-托合成性能的影响

徐润   

  1. 中国石化石油化工科学研究院
  • 收稿日期:2015-06-05 修回日期:2015-08-11 出版日期:2015-12-12 发布日期:2015-11-26
  • 通讯作者: 徐润 E-mail:xurun.ripp@sinopec.com
  • 基金资助:

    中国石油化工股份有限公司合同项目

EFFECT OF ADDITION OF LIQUID HYDROCARBONS ON PERFORMANCE OF COBALT-BASED CATALYST IN FIXED-BED FISCHER-TROPSCH SYNTHESIS

  • Received:2015-06-05 Revised:2015-08-11 Online:2015-12-12 Published:2015-11-26

摘要:

为解决固定床费-托合成中因传热限制而产生热点导致反应恶化的问题,将费-托合成产生的轻质油与原料气共同引入反应器,在中型装置上以工业RFT-2钴基固定床费-托合成催化剂为研究对象,考察轻质合成油空速、组成对费-托合成性能、催化剂床层温度分布、产品分布的影响。结果表明:轻质合成油的注入有利于降低CO2的选择性,降低液体产品的烯烃含量;随注油空速的增加,甲烷选择性升高,C5+选择性略有降低,催化剂床层温度分布显著改善,热点消失。将轻质合成油分成不同的馏分段注入反应器,随着注入馏分的变重,甲烷和C5+的选择性均降低,催化剂床层温度分布的均匀性提高。因此,轻质合成油的注入不仅可以改善催化剂床层温度分布、提高费-托合成性能,而且可以通过调整注入的轻质合成油组成来获得不同的产品组成。

关键词: 费-托合成, 固定床, 轻质合成轻油, 循环, 温度分布, 产品分布

Abstract:

In order to avoid thermal instability in the catalytic bed during Fischer-Tropsch synthesis, the light synthetic oil and feed gas were co-fed into the reactor. The effect of light synthetic oil on the performance of cobalt-based catalyst was investigated in a fixed-bed reactor by changing space velocity and light oil compositions. The light synthetic oils are found to have a positive effect on decreasing the selectivity of CO2. Increase of liquid space velocity leads to an increase of methane selectivity and a decrease of C5+ selectivity. The content of olefin decreases significantly. The local hot spots in the bed are no longer present. The temperature distribution of the catalytic bed is improved. As the light oil fed into the bed becomes heavier, the selectivity of methane and C5+ are both decreased, while the temperature distribution of the catalyst bed is further improved. It is concluded that the addition of light synthetic oil can not only improve the temperature gradient and catalyst performance, but also can adjust the F-T product distributions by changing the composition of the light synthetic oils.

Key words: Fisher-Tropsch synthesis, fixed-bed, light synthetic oil, recycle, temperature distribution, product distribution