Hebei Messi Biology Co., Ltd. stated that it initially selected anionic surfactant sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, sodium dodecyl sulfonate, nonionic surfactant alkylphenol polyoxyethylene ether (OP-10), pentahydrate sodium metasilicate, and polyepoxysuccinic acid as additives to prepare slurry magnesium hydroxide with good stability and fluidity, but the dosage is large and the cost is high. Therefore, the three were compounded for orthogonal experiments.
When the addition amount of sodium metasilicate is 0.3%, the addition amount of OP-10 is 2.4%, and the addition amount of polyepoxysuccinic acid is 0.7%, the stability percentage of the slurry is the highest, and the stability percentage of the obtained slurry is 91.78%, the initial viscosity is 580mPaos, and the viscosity is 620mPaos after one week of placement. There is no stratification phenomenon, which meets the requirements of stability slurry.
Hebei Messi Biology Co., Ltd. uses brine as raw material and ammonia water as precipitant to prepare slurry magnesium hydroxide. Through the analysis of the influencing factors in the synthesis process of magnesium hydroxide and the analysis of the influencing factors in the synthesis process of slurry magnesium hydroxide, the following conclusions can be drawn:
(1) Taking into account the magnesium precipitation efficiency and sedimentation time of magnesium hydroxide prepared by the brine ammonia method, the optimal conditions for preparing magnesium hydroxide are: the addition method is to add ammonia water and brine at the same time, the brine concentration is 4.2 mol/L, the pH value of ammonia water is 12.2, the reaction temperature is 55℃, and the brine addition rate is 3.0m1/min. The magnesium precipitation efficiency of magnesium hydroxide prepared under this experimental condition is about 74.8% and the sedimentation time is about 18.9 hours.
(2) The dispersibility of polyepoxysuccinic acid prepared at a polymerization temperature of 86℃ and an initiator addition amount of 2.5% is the highest.
(3) A single dispersant cannot make the slurry meet the requirements of stable slurry. Among the composite dispersants, the dispersant made of sodium metasilicate + 0P-10 + polycyclohydrosuccinic acid has the best effect. When the addition amount of sodium metasilicate is 0.3%, the addition amount of OP-10 is 2.4%, and the addition amount of polyepoxysuccinic acid is 0.7%, the stability percentage of the slurry after one week is as high as 91.78%, the initial viscosity is 580mPa s, and the viscosity is 620mPa s after one week. There is no stratification after three weeks, and it still has good fluidity and meets the requirements of stability slurry.