【摘要】 以磷矿石生产磷肥的有害废弃物氟硅酸为基础原料,采用两步氨化法制备了高纯度白炭黑。研究了反应时间、反应温度、氨水质量分数和氨水用量等工艺条件对产品质量的影响,获取了两步氨化技术优化工艺参数。第一步氨化的优化条件:反应温度为45℃,反应时间为10min,氨水的质量分数为13%,氨水用量为理论用量的60%;第二步氨化的优化条件:反应终点pH为9,反应温度为50℃,搅拌转速为260r/min。所得二氧化硅各项性能指标大部分达到HG/T3061—1999标准。该技术工艺流程简单、设备利用率高、消耗低,达到了充分利用矿产资源,降低产品成本的目标。更多还原

【Abstract】 High purity silica was synthesized through two-step ammonification method by using waste fluorosilicic acid,a hazardous waste material,by-produced in the production of phosphate fertilizer from phosphorite as raw material.Effects of process conditions,such as reaction time,reaction temperature,mass fraction and addition amount of ammonia on the product quality,were investigated,and optimized parameters of two-step ammoniation technology were obtained.Optimized conditions of the first ammoniation step were:reaction temperature of 45 ℃,reaction time of 10 min,mass fraction of ammonia of 13%,and addition amount of ammonia was 60% of the theoretical amount.The second step were:reaction terminal pH of 9,reaction temperature of 50 ℃,and stirring speed of 260 r/min.The most of indexes of the prepared silica reached HG/T 3061—1999 standard.The tecnology has simple process flow,better use of equipment and low consumption,and reaches the prospective target of taking full advatage of mine resource and lowing the cost of products.更多还原