Abstract: <SPAN lang=EN-US>A new manufacturing technology of ammonium fluoride white carbon black was studied.Fluosilicic acid is the by-product in production of phosphate fertilizers.With certain temperature,adjusted pH,and controlled reaction time,fluosilicic acid was dissolved in the solution of ammonia liquor,and then runny paste of silica and solution of ammonium fluoride were obtained after seperating the reaction slurry.After washing and drying,white carbon black was obtained from the runny paste.Ammonium fluoride solution was concentrated,crystallined and dehydrated to get ammonium fluoride.Ammonia produced in the production process can be absorbed and recycled.Ammonium fluoride produced by the new technology has many virtues,such as low cost,recycling utilization for fluoride and silicate resources,energy-saving,and environmental benignancy.The quality of products is good which could meet the national standard.<BR></SPAN>