Multiphase catalytic reactors for methanol-to-olefins

doi:10.3969/j.issn.0438-1157.2014.07.009

Abstract

Abstract: The methanol-to-olefins (MTO) and methanol-to-propylene (MTP) processes are important ways to convert coal to chemicals. Successfully commercialized processes in recent years include the DMTO, s-MTO, MTO+OCP and MTP technologies developed respectively by Dalian Institute of Chemical Physics, SINOPEC, UOP and Lurgi. This paper analyzes the characteristics of the heterogeneous catalytic reactions in the MTO process, and on this basis discusses various multiphase catalytic reactors used for converting methanol to olefins. Key features and specifications of different technologies, and the similarity and difference between the MTO and fluidized catalytic cracking processes are compared. The MTO reactions occur by hydrocarbon pool reaction mechanism, which has autocatalytic and coking deactivation behavior that makes it important to control the working state of the catalyst and limit back-mixing in the reactor to achieve good activity and olefin selectivity. The use of a hierarchical zeolite catalyst and a fluidized bed reactor with little back-mixing or a reactors-in-series assembly is suggested as potential improvement for the process.

Key words: methanol to olefins, catalysis, reaction mechanism, reactor, deactivation and regeneration

摘要： 甲醇制低碳烯烃（MTO、MTP）是煤化工的关键环节，近年来相关技术已经在我国成功工业化，包括中国科学院大连化学物理研究所的DMTO技术、中石化的s-MTO技术、UOP的MTO+OCP技术以及Lurgi的MTP技术。从非均相催化反应角度分析甲醇制烯烃的过程特点，剖析了各类典型的非均相催化反应器用于该过程的优劣，对比了国内外各主流技术的关键指标，评述了甲醇制烯烃和催化裂化的异同。分子筛催化的甲醇制烯烃过程遵循烃池机理，呈现自催化和积炭失活特性，控制催化剂的工作状态和限制返混对提高催化活性及烯烃产物选择性尤为重要。具有多级结构的分子筛催化剂及低返混流化床反应器或反应器串联组合是未来的发展方向。

关键词: 甲醇制烯烃, 催化, 反应机理, 反应器, 失活与再生

CLC Number:

TQ028.8

WANG Yao, DI Zuoxing, LI Yuxin, WANG Dezheng, WEI Fei. Multiphase catalytic reactors for methanol-to-olefins[J]. CIESC Journal, 2014, 65(7): 2474-2484.

王垚, 狄佐星, 李玉新, 王德峥, 魏飞. 用于甲醇制烯烃的非均相催化反应器评述[J]. 化工学报, 2014, 65(7): 2474-2484.

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