The invention relates to a preparation method of aluminum hydroxide, particularly a preparation method of high-dispersity superfine aluminum hydroxide. The method is characterized by comprising the following steps: carrying out two-stage seed decomposition by using nano active aluminum hydroxide prepared by the reaction between a sodium aluminate solution and an aluminum sulfate solution as a seed, carrying out solid-liquid separation and washing on the obtained decomposition pulp, and carrying out mechanical stirring and grinding to prepare the superfine aluminum hydroxide. The superfine aluminum hydroxide prepared by the method has complete crystal form, effectively solves the problem of aggregation of the superfine aluminum hydroxide, and solves the problem of secondary granularity caused by aggregation; and the method enhances the dispersity of the superfine aluminum hydroxide, and lowers the oil absorption number of the superfine aluminum hydroxide to 28-32ml/100g.

Preparation method of aluminum hydroxide

The invention discloses a micro-powder aluminum hydroxide preparation method and device and micro-powder aluminum hydroxide. The preparation method comprises the steps of adding aluminum hydroxide seed crystals obtained through carbonation decomposition of a sodium aluminate solution into the sodium aluminate solution to perform variable-temperature seed decomposition to obtain decomposition slurry; removing iron in the decomposition slurry to obtain a first intermediate product; washing the first intermediate product to depolymerize the first intermediate product to obtain a second intermediate product; removing water in the second intermediate product to obtain a third intermediate product; scattering and grading the third intermediate product to obtain micro-powder aluminum hydroxide. The preparation device comprises a decomposition tank, an iron removing device, a first washing device, a depolymerization device, a water removing device, and a scattering and grading device. The micro-powder aluminum hydroxide is prepared by using the preparation device according to the preparation method, such that the grain distribution of the micro-powder aluminum hydroxide product with a median particle diameter of 1mu m is even, the oil absorption is reduced to 30mL/100g to 35mL/100g, the impurity content of the obtained product is low, the whiteness is high and the product quality is stable.

Micro-powder aluminum hydroxide preparation method and device and micro-powder aluminum hydroxide

The invention provides a method for preparing aluminum hydroxide micro-powder with a low oil absorption rate, which comprises the following steps of: taking a sodium aluminate solution as a raw material, adding a ground active seed crystal to the raw material, sorting and decomposing ultrathin aluminum hydroxide pulp, continuously heating the ultrathin aluminum hydroxide pulp for aging and decomposition, and then drying to obtain the aluminum hydroxide micro-powder with a low oil absorption rate. Sequential decomposition and aging are increased on the basis of the original technical processes for preparing the aluminum hydroxide micro-powder with the sodium aluminate solution, and the prepared aluminum hydroxide micro-powder has a low oil absorption rate and a high extrusion speed. The operation process is simple and feasible, and the product quality is obviously improved.

Method for preparing aluminum hydroxide micro-powder with low oil absorption rate

The invention relates to a preparation method for micropowder aluminum hydroxide. Wherein, adding aluminum hydroxide as crystal seed into the material of sodium aluminate solution; liquid-solid separating the slurry, clearing and baking the solid; then using gas flow grinder for depolymerisation and stepped treatment to obtain the final product. Compared with prior art, this invention improves product quality and purity obviously, and reduces oil suction quantity and conductivity and sodium oxide content in product greatly.

Method for preparing aluminium hydroxide micropowder

The invention provides a method for manufacturing superfine aluminum hydroxide micropowder and relates to a method for manufacturing superfine aluminum hydroxide by using Bayer lotion. The method is characterized by utilizing Bayer red mud lotion to manufacture the superfine aluminum hydroxide micropowder by seed crystal decomposition. The domestic production of the superfine aluminum hydroxide micropowder in prior arts adopts sintering process refined liquid; however, only few factories at home manufacture aluminum hydroxide by a sintering process and the capacity is less than 5% of that of aluminum oxide at home and the production cost is high, so that the method for manufacturing the superfine aluminum hydroxide micropowder by using the Bayer lotion has the advantages of wide source of raw materials and low cost. The method for manufacturing the superfine aluminum hydroxide micropowder of the invention is characterized by utilizing the Bayer red mud lotion to manufacture the superfine aluminum hydroxide micropowder by the seed crystal decomposition; after the decomposition, slurry is filtered, washed and dried to obtain a superfine aluminum hydroxide product with the diameter of D50=0.8-2 microns, whiteness more than 95 and oil absorption value of 35-39ml/100g. According to the method provided by the invention, the difficulties that the supply amount of the sintering process refined liquid is small and the cost is high are overcome, and a high-quality production way capable of meeting the supply need of the superfine aluminum hydroxide micropowder is provided.

Method for manufacturing superfine aluminum hydroxide micropowder

A process for preparing superfine aluminium hydroxide powder with low electric conductivity includes such steps as desiliconizing the solution of sodium aluminate, adding crystal seeds, decomposing, filtering, washing the filtered cake, refiltering, and baking

Zhu Dexue

Papers

Preparation method low electric conductiving super fine aluminium hydroxide micro powder