Preparation method of wear-resistant microspheroidal silica carrier

Abstract

The invention provides a preparation method of a wear-resistant microspheroidal silica carrier. The preparation method comprises roasting precipitation silica powder or white carbon black with a specific surface area of 250-600m<2>/g at a temperature of 730-760 DEG C so that a specific surface area is reduced to 100-220m<2>/g, adding water into the roasting product, carrying out uniform mixing, carrying out grinding dispersing to obtain microparticles with the average diameter of 2-5 microns, adding acetic acid and ammonium acetate into the microparticles, carrying out crystallization treatment at a temperature of 150-180 DEG C, adding a white carbon black emulsion into the treated microparticles, carrying out uniform mixing, carrying out spray granulation and roasting the granule powder to obtain microspheroidal carriers with the average diameter of 50-250 microns, a specific surface area of 80-200m<2>/g, a pore volume of 0.5-0.7ml/g and the average pore diameter of 20-40nm. The wear-resistant microspheroidal silica carrier has high mechanical strength, wear resistance and impact resistance, is suitable for further loading with active components and can be used for preparation of a fluidized bed catalyst.

Description

technical field [0001] The invention belongs to the field of catalysts, and relates to a method for preparing a microspherical silica carrier, in particular to a method for preparing a wear-resistant and impact-resistant microspherical silica carrier. Background technique [0002] In addition to having a suitable pore structure, the catalyst should also have high mechanical strength and wear resistance, especially in the fluidized bed, between catalyst particles, between catalyst particles and the inner wall of the reactor, between catalyst particles and the solid phase in the fluidized bed There will be frequent friction and collision between the reaction raw materials or products, and the formed broken particles will expand the fluidized bed layer, and the formed finer powder, such as the part below 10-15um, is easy to blow off the fluidized bed, basically Scrapped. [0003] Preparing the carrier first, and then impregnating the active component is the most commonly used ...

AI Technical Summary

Problems solved by technology

[0004] However, preparing a microspherical silica carrier with suitable pore structure, mechanical strength and wear resistance is a technical problem in this field, because silica raw materials such as precipitated silica and fumed silica are usually sintered The performance is poor; using silica sol as a binder can improve the mechanical strength and wear resistance of the silica carrier, but the effect is limited. Even after recrystallization treatment such as hydrothermal treatment, the wear resistance of the carrier cannot be greatly improved

Using alumina, calcium oxide, kaolin, etc. as a binder can also improve the mechanical strength and wear resistance, but under acidic conditions, the acid-resistant components contained in the binder will be eroded, making the mechanical strength and wear resistance of the carrier Abrasiveness will gradually decrease

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