Clean synthesis method of iron oxide red pigment with low oil absorption

Abstract

The invention provides a clean synthesis method of an iron oxide red pigment with low oil absorption. The method comprises the following steps: 1, preparation: adding 30-50 parts of FeSO4.7H2O into an auxiliary agent, and dissolving to prepare a solution A; 2, primary crystallization: mixing the solution A obtained in the step 1 with a NaOH solution B, and then precipitating and uniformly oxidizing to prepare gamma-FeOOH primary seed crystal; 3, secondary crystallization: adding the gamma-FeOOH primary seed crystal suspension prepared in the step 2 into the solution A in the step 1, stirring and oxidizing, and adding a NaOH solution B to prepare gamma-FeOOH secondary seed crystal; 4, tertiary crystallization: adding the gamma-FeOOH secondary seed crystal obtained in the step 3 into the solution A obtained in the step 1, adding a NaOH solution B at the same time, and stirring and oxidizing to obtain gamma-FeOOH tertiary seed crystal; and 5, preparation of a finished product of iron oxide red: preparing a FeSO4.7H2O solution, heating the gamma-FeOOH tertiary seed crystal suspension obtained in the step 4, then adding the FeSO4.7H2O solution, heating, and carrying out suction filtration, washing, drying and grinding to obtain the finished product of iron oxide red.

Description

technical field

[0001] The invention relates to a clean synthesis method of iron oxide red pigment with low oil absorption. Background technique

[0002] In recent years, my country's inorganic pigment industry has developed rapidly. Among all kinds of pigments, iron oxide pigments have become the largest color inorganic pigments. The amount of waste water in the production process of iron oxide products is large, especially the mixed acid method (nitric acid-sulfuric acid) is used in the production process of iron red pigments, which will produce high-concentration ammonia nitrogen waste water. The waste water volume fluctuates greatly, the concentration of NH3-N is high, and the treatment is difficult It is one of the factors leading to the eutrophication of closed water bodies and one of the pollutants strictly controlled by the state. According to statistics, 20 tons of water is used for each ton of iron red pigment products, and the concentration of ammonia nitrogen in...