| Silica powder is the most common in nature, one of the most common siliceous mineral raw materials. Because it has good temperature resistance, acid and alkali corrosion resistance, high insulation, low thermal expansion, stable chemical performance, high hardness, such as excellent physical and chemical properties, are widely used in chemical industry, electronics, integrated circuit (IC), electrical appliances, plastics, coating, senior paint, rubber, defense and other industries areas, is a kind of inorganic nonmetallic materials are very versatile. With high and new technology and the rapid development of electronic information technology, silica powder will enter a new historical development period in the coming years, its application is more and more broad, and at the same time of silica powder quality put forward higher request.The siliceous raw material resources of our country is rich, if we can carry on the reasonable purification processing, to meet growing market demand, is of great significance to promote the development of new energy. This thesis defense in Puge, Sichuan vein quartz processing quartz silica powder as the research object, mainly from the pickling formula and silica powder quality relationship,the process parameters research of vein quartz preparation for quartz silica powder, vein quartz processing quartz silica powder optimization process and application. Using inductively coupled plasma emission spectrometer (ICP-OES) of PE companies in the United States production, IC1010ion chromatograpH, DDS-11A conductivity meter, pHS-3+acidity meter for chemical composition analysis, the water extracted liquid analysis (mainly Na+, Cl-, conductivity, pH). Comprehensive comparative study and choose optimal formula from the satisfy3N quartz silica powder quality indicators, and to research further the main factors influencing the effect of acid leaching are pickling time, pickling temperature, solid-liquid ratio, acid concentration, particle size, respectively analysis the data of chemical composition and the water extract, from meet the3N quartz silica powder quality indicator parameters to identify the optimize process conditions, finally applies the process respectively to TNA01-01B/TNA01-02B vein quartz for getting corresponding quartz silicon powder. The research results obtained in this paper and the experiment progress is as follows:1. Acid formula relationship with quartz silica powder qualityUsing ICP-OES, ion chromatograph, conductivity meter, pH meter to analyze undressed ore and by acid leaching processing TNA01-01B sample. Analyzing of the chemical composition and the water extract liquid showed that under the condition of acid leaching time4h,pickling temperature90℃, solid liquid ratio1:2, sample granularity of-40meshes, the6#acid formula (20%H2SO4+5%HF) is best pickling effect, according to this formula processed sample chemical composition and the water extract liquid of Na+, Cl-, electrical conductivity, pH can achieve the ideal effect.2. The process parameters research of vein quartz preparation quartz silica powder(1) Acid immersion time relationship with quartz silica powder quality:from the point of chemical composition analysis, acid leaching2h,4h,5h can satisfy the production level of3N quartz silica powder chemical composition requirements; from the point of water extracted liquid analysis, five kinds of acid leaching time scheme can satisfy the test requirements. Based on the analysis of chemical composition analysis and the water extract liquid of results and improve the efficiency of production factors, such as saving time, finally choosing the optimization parameter is pickling time2h.(2) Pickling temperature relationship with quartz silica powder quality:from the chemical composition analysis and the water extract liquid analysis, five kinds of acid leaching temperature scheme all can satisfy the production level of3N quartz silica powder chemical composition and water extract liquid requirements. Comprehensive test results and the production cost and so on various aspects factors, finally choosing the optimized parameter is pickling temperature70℃.(3) Solid-liquid ratio and quartz silica powder quality relationships:from the point of chemical composition analysis, solid liquid ratio of1:1,1:3,1:5all can satisfy the production level of3N quartz silica powder chemical composition requirements; The analysis water extract liquid, five kinds of solid-liquid ratio scheme both can satisfy the production level of3N quartz silica powder water extract liquid requirements. Comprehensive factors such as test results and save acid to reduce the production cost, finally selecting the optimization parameter is solid-liquid ratio1:1.(4) Acid concentration and quartz silica powder quality relations:from the point of chemical composition analysis, in addition to the acid concentration is0%HF+10%H2SO4both can satisfy the production level of3N quartz silica powder chemical composition requirements; From the analysis of water extract liquid, in addition to the10%HF+15%H2SO4to the rest of the all can satisfy the production level of3N quartz silica powder water extract liquid requirements. Due to the acid concentration is too high, on the one hand, would increase the cost of washing times and waste liquid treatment; on the other hand equipment corrosion would intensify, it’s obviously undesirable. Comprehensive experimental results and the factors, and ultimately choosing the optimization parameter is acid concentration2.5%HF+10%H2SO4.(5) Sample granularity and quartz silica powder quality relations:from the chemical composition analysis and the analysis of water extract liquid, three kinds of sample granularity scheme all can satisfy the production level of3N quartz silica powder chemical composition and water extract liquid requirements. Comprehensive test results and the production cost of graded sieving and so on various aspects factors, finally choosing the optimized parameter is sample size-40meshes.(6) To sum up, optimize the process conditions is:pickling time2h, pickling temperature70℃, solid liquid ratio1:1, acid concentration2.5%HF+10%H2SO4, sample granularity-40meshes.3. Vein quartz processing quartz silica powder optimization technology and application(1) Electronic grade quartz silica powder processing technology:Using ICP-OES, ion chromatograph, conductivity meter, pH meter to analyze sample TNA01-02BG, which by the optimization of process condition dealing with. Analyzing of the chemical composition and the water extract liquid showed that under the condition of acid leaching time2h, pickling temperature70℃, solid liquid ratiol:1, acid concentration10%H2SO4+2.5%HF,sample granularity-40meshes, after processing the sample of the chemical composition and the water extract liquid of Na+, Cl-, electrical conductivity, pH can satisfy electronic grade quartz silica powder quality requirements.(2) High-purity quartz silica powder processing technology:Using ICP-OES, ion chromatograph, conductivity meter, pH meter to analyze sample TNA01-01BG, which by the optimization of process condition dealing with. Analyzing of the chemical composition and the water extract liquid showed that under the condition of acid leaching time2h,pickling temperature70℃, solid liquid ratiol:1, acid concentration10%H2SO4+2.5%HF,sample granularity-40meshes, after processing the sample of the chemical composition and the water extract liquid of Na+, Cl-, electrical conductivity, pH can meet the high-purity quartz silica powder quality requirements.(3) From what has been discussed above, the optimized technological conditions suitable for electronic grade quartz silica powder and high-purity quartz silica powder production. |
