Preparation Process of Magnesium Hydroxide by Dunite

摘要

The preparation process of magnesium hydroxide, which was prepared by acid leaching method using dunite as material, was introduced. Dunite was firstly calcined for 4 h at 700°C and treated by 4.0 mol/L of H_2SO_4 solution at 100°C for 2 h. Secondly, the leaching solution was oxidized by H_2O_2, and ammonia was added in the solution to adjust its pH to 7.0-8.0. After the impurities were leached, the leaching solution was treated by 4.0 mol/L of NaOH and 2% of C_(11)H_(23)COONa, reacting for 1 h, ageing for 2 h. Then to obtain dried magnesium hydroxide, the insoluble compounds were dried by heat and magnesium hydroxide would be produced. The leaching rate of Mg~(2+) is 84.01%. XRD and SEM indicated that the shape of particles was platelet with a diameter of 150 nm. The product can reach the requirements of HG/T3607-2007 industrial product standard.