Bifunctional catalyst containing multi-stage pore EUO molecular sieve and preparation method thereof

Abstract

The invention discloses a bifunctional catalyst containing a multi-stage pore EUO molecular sieve and a preparation method thereof. The catalyst comprises 10 to 90wt% of an H-type multi-stage pore structure EUO molecular sieve, 9.9 to 89.9wt% of a matrix and 0.01 to 2.0wt% of a metal active component. The preparation method comprises: mixing multi-stage pore EUO molecular sieve raw powder, the matrix and a pore-expanding agent, adding an acid solution into the mixture, carrying out mixing kneading shaping, carrying out drying and roasting to remove the pore-expanding agent so that a carrier isformed, and dipping the carrier in a mixed solution containing a metal salt for activation to obtain a shaped catalyst. The multi-stage pore EUO molecular sieve is synthesized by crystallization of along-chain silane compound as a crystallization aid and a double-quaternary ammonium salt as an organic template with a double six-membered heterocyclic group substituted alkane structure. The catalyst exhibits good activity and selectivity in the hydroisomerization reaction of a C8 aromatic hydrocarbon and has a good industrial application prospect and economic value.

Description

technical field [0001] The invention relates to a bifunctional catalyst containing multi-level porous EUO molecular sieves and a preparation method thereof, belonging to the field of preparation of inorganic catalytic materials. Background technique [0002] C 8 Aromatics are a mixture of p-, m-, ortho-xylene and ethylbenzene, which can be obtained from catalytic reforming, petroleum cracking and other processes, among which p-xylene (PX) and o-xylene (OX) are important chemical raw materials , such as the basic raw material for polyester and phthalic anhydride. With the development of these industries, the demand for PX and OX is increasing rapidly. At present, the process technology for increasing the production of PX and OX is mainly xylene isomerization, which is an important means to convert m-xylene and ethylbenzene with low utilization value into PX and OX. Since the boiling points of ethylbenzene and xylene are very close, the separation is difficult, resulting in...

AI Technical Summary

Problems solved by technology

While catalysts based on ZSM-5 zeolite, which can be used alone or in combination with other zeolites such as mordenite, do not provide the best performance

[0006] CN1901991A discloses a kind of C 8 Aromatics isomerization catalyst, using MTW type zeolite or low silica ZSM-12 as the acidic component, platinum and germanium as active metal components, when the above catalyst is applied to the isomerization of C8 aromatics, although the conversion rate of ethylbenzene is relatively low High, but the loss rate of xylene is high, indicating that there are many side reactions, the selectivity of the catalyst is poor, and the p-xylene in the product stream has not reached the equilibrium quantity

[0010] The EUO structure molecular sieve preparation methods disclosed in the above documents mainly include traditional hydrothermal method and solid-phase in-situ method, but the molecular sieve structure is basically the same, its particle size is generally large, all in the micron level, and miscellaneous crystals are prone to appear. The lifespan is severely limited, and the product yield needs to be improved

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