Catalyst used for alkylation of methanol, C10 aromatic hydrocarbons and 2-methylnaphthalene for synthesizing 2,6-dimethylnaphthalene

Abstract

The invention relates to a catalyst used for alkylation of methanol, C10 aromatic hydrocarbons and 2-methylnaphthalene for synthesizing 2,6-dimethylnaphthalene, and mainly solves the problems of low conversion rate of the 2-methylnaphthalene, low selectivity of the 2,6-dimethylnaphthalene and low stability of the catalyst in the conventional synthesis process technology. In the technical scheme of the invention, the catalyst comprises the following components in part by weight: 50 to 95 parts of one or a mixture of any two of hydrogen-type silicon-aluminum zeolites, 5 to 50 parts of binder and 1.0 to 15 parts of metal oxide of at least one of transition metal, rare-earth metal and alkaline-earth metal; and the reaction conditions for synthesizing the 2,6-dimethylnaphthalene are that: temperature is between 360 and 500 DEG C, pressure is between 0 and 7.5MPa, the molar ratio of the methanol to the 2-methylnaphthalene is between 1.0 and 3.0, the weight ratio of the C10 aromatic hydrocarbons to the 2-methylnaphthalene is between 1.0 and 6.0, and air speed is between 0.1 and 3.5 hour<-1>. The catalytic reaction ensures relatively high synthesis yield of the 2,6-dimethylnaphthalene, and the problems in the prior art are well solved.

Description

technical field [0001] The invention relates to a catalyst for synthesizing 2,6-dimethylnaphthalene by alkylation of methanol, carbon ten aromatic hydrocarbons and 2-methylnaphthalene. Background technique [0002] 2,6-dimethylnaphthalene (2,6-DMN) is considered to be the most ideal raw material for the production of high-performance polyester material-polyethylene naphthalate (PEN). At present, only the BP-Amoco process of 2,6-dimethylnaphthalene industrialized production method has low yield, many steps, and serious pollution of by-products (Asian Chemical News, Nov.16, 1998; Chemical Market Reporter, Aug.2, 1999). Therefore, the new 2,6-dimethylnaphthalene synthesis process has attracted more and more attention. The direct synthesis of 2,6-dimethylnaphthalene by alkylation of methylnaphthalene and methanol is simple and efficient, but the reaction yield is low and the catalyst is easily deactivated, which limits its industrial application. US4795847 (J weitkamp et al.)...

AI Technical Summary

Problems solved by technology

The direct synthesis of 2,6-dimethylnaphthalene by alkylation of methylnaphthalene and methanol is simple and efficient, but the reaction yield is low and the catalyst is easily deactivated, which limits the industrial application of this technology

US4795847 (J weitkamp et al.) reported that methylnaphthalene and methyl alcohol carried out alkylation reaction on ZSM-5, after reacting for 0.5 hours, the selectivity of 2,6-dimethylnaphthalene product was 32%, but methyl The conversion rate of naphthalene is only 7%; as the reaction time prolongs, the conversion rate of methylnaphthalene is basically unchanged, but the selectivity of 2,6-dimethylnaphthalene will decrease

CN1151107C (Bai Xuefeng, Liu Wenbin, Xia Yuanliang, etc.) reported that Mg 2+ The exchanged ZSM-5 molecular sieve catalyzed the alkylation reaction of naphthalene or methylnaphthalene with methanol. The results showed that the selectivity of 2,6-dimethylnaphthalene was close to 36%, but the conversion rate of methylnaphthalene was less than 10%.

In addition, WO02060581 (Lillwita et al.) reported that FeF 3 and NH 4 HF 2 The alkylation reaction of methylnaphthalene and methanol on the modified HZSM-5 molecular sieve can obtain 2,6-dimethylnaphthalene selectivity of 60%, and the ratio of 2,6- / 2,7-dimethylnaphthalene It can also reach 1.8-2.2, but the conversion rate of methylnaphthalene is very low

[0003] In conclusion, at present, the catalyst and reaction process for the synthesis of 2,6-dimethylnaphthalene by the alkylation reaction of methylnaphthalene and methanol have the serious shortcomings of low product yield and easy deactivation of the catalyst, which limits the process of its industrial application

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