Alumina hydrate composition containing ZSM-12 type molecular sieve, catalyst, preparation method and hydroisomerization method

Abstract

The invention discloses a hydrated alumina composition containing a ZSM-12 molecular sieve and a preparation method thereof and a molded body and a preparation method and application thereof. The composition contains hydrated alumina, the ZSM-12 molecular sieve and a compound with at least two proton acceptor sites and with the value of phi of 5 or less. The present invention also discloses a hydroisomerization catalyst using the molded body prepared from the hydrated alumina composition as a carrier, a preparation method and a hydroisomerization method. The molded body with higher strength isprepared from hydrated alumina wet gel as a starting material, the step of drying of the hydrated alumina wet gel is omitted, the overall process flow is simplified, the overall operation energy consumption is reduced, dust pollution caused by use of pseudoboehmite dry powder as a raw material is avoided, and the working environment is greatly improved. The catalyst shows a higher catalytic activity in the hydroisomerization reaction.

Description

technical field [0001] The present invention relates to the technical field of alumina molding, in particular, the present invention relates to a hydrated alumina composition containing ZSM-12 molecular sieve and its preparation method, and the present invention also relates to the hydrated alumina formed from the hydrated alumina composition. Aluminum molded body and alumina molded body, the present invention further relates to a hydroisomerization catalyst using the molded body formed from the hydrated alumina composition as a carrier, a preparation method thereof, and a hydroisomerization process using the catalyst method. Background technique [0002] ZSM-12 molecular sieve was synthesized for the first time in 1974 by Rosinski et al., Mobil Company of the United States. ZSM-12 has a one-dimensional linear non-intersecting channel composed of twelve-membered rings, with a pore diameter of ZSM-12 belongs to the monoclinic crystal system (C2 / m), the structure type is MT...

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Problems solved by technology

[0015] (1) Pseudo-boehmite that has not been completely dried has strong viscosity, is difficult to transfer, and easily causes secondary dust pollution;

[0016] (2) Drying starts from the surface. The drying of the wet solid product separated from the mixture obtained from the gelling reaction is incomplete drying, so there is a sandwich biscuit phenomenon, that is, the surface of part of the pseudo-boehmite is dried (that is, the surface that is dried does not contain free water), while the interior remains wet (that is, for the interior that has not been dried, the content of free water basically remains at the level before drying), since the surface is dried, Therefore, hard particles are formed. When peptizing agent and / or binder are added to this incompletely dried pseudo-boehmite and kneaded, the hard particles formed during the drying process are in the process of extrusion. It is easy to cause blockage and affect production efficiency;

[0017] (3) It is difficult to stably control the dry base of pseudo-boehmite. The instability of the dry base will cause great interference to the molding process, making the molding process very unstable, resulting in an increase in the amount of unqualified products and low production efficiency;

[0018] (4) CN103769118A adopts a conventional molding process during molding, but because the dry basis (35%-50%) of the pseudo-boehmite it uses is far lower than the conventional dry basis content (about 70%), that is The water content is high, and there is basically no extrusion pressure during the extrusion molding process. Therefore, the carrier obtained after the extrudate is dried and roasted has basically no mechanical strength. As long as a little external force is applied, it will be pulverized and has no possibility of industrial application. sex, which is the biggest problem facing the technology

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