粉煤灰精细化制备氧化铝和白炭黑
发布时间：2019-01-03 16:09
【摘要】：作为对环境影响极大的粉状固体工业废物—粉煤灰,对土地、水质、空气都有不同程度的污染,对人类的生产和生活均十分不利。故探讨粉煤灰在铝硅产品方面的精细化利用,其中化学成分提取纯化后,按晶型、粒径、比表面积等分级制备高附加值的产品,不但提高了粉煤灰的市场价值,而且有利于环境生态文明建设。本文在课题组前人的研究基础上,实现粉煤灰的铝硅产品的精细化和多元化,甚至功能化。通过实验的设计和研究,工艺条件的优化结果如下:(1)粉煤灰与Na2C03按灰碱比为1:0.9研磨混匀,875 ℃焙烧活化2h,加入浓度为3mol/L 的H2SO4将焙烧物酸浸后过滤,滤渣作制备硅产品备用,滤液经结晶和重结晶提纯,烘干制备Al2(SO4)3产品;利用NH3·H2O与Al2(O4)3产品反应,过滤后干燥生产Al(OH)3产品。(2)将A12(SO4)3产品与Na2CO3按铝钠比1:3.5搅拌混溶均匀,同时水浴加热进行反应,制备中间产物勃姆石(即铝的水合氧化物,化学式为Al2O3·nH20)。此段反应的最佳工艺条件为:水浴反应温度为60℃;反应时间为30min。(3)在A1203前躯体焙烧时,为实现完全的晶型转化和制备较纯的氧化铝晶型,并制备出合适的纳米级产品,选取600℃的焙烧温度,效果较佳。(4)焙烧活化及酸浸后的滤渣1,再次经热碱浸过滤提纯,此时得滤渣2返回至滤渣1,循环利用,滤液中加H2SO4制酸溶胶。最佳的工艺为:制酸溶胶的H2SO4浓度为3.0mol/L;此时产品的比表面积和DBP吸收值均较大;(5)硅酸溶胶制备超细白炭黑时,为限制晶粒的团聚,需加入复合分散剂,从而制备粒径更小的白炭黑。最佳工艺参数为:粉煤灰与复合分散剂的比值为0.10%,反应温度为60℃,反应时间为35min,制得结构组成中具有轻基结构水的SiO2产品。
[Abstract]:Fly ash, a powdered solid industrial waste, which has a great impact on the environment, pollutes the land, water quality and air to varying degrees, and is unfavorable to the production and life of human beings. Therefore, the fine utilization of fly ash in Al-Si products is discussed. After extracting and purifying the chemical components, the high value-added products are prepared according to the gradation of crystal form, particle size and specific surface area, which not only improve the market value of fly ash, but also improve the market value of fly ash. And is advantageous to the environment ecology civilization construction. In this paper, based on the previous research, the aluminum and silicon products of fly ash are refined and diversified, even functionalized. Through the design and study of the experiment, the optimized technological conditions are as follows: (1) the fly ash and Na2C03 are mixed at 1: 0.9 ratio of ash to alkali, roasted at 875 鈩，
本文编号：2399598
[Abstract]:Fly ash, a powdered solid industrial waste, which has a great impact on the environment, pollutes the land, water quality and air to varying degrees, and is unfavorable to the production and life of human beings. Therefore, the fine utilization of fly ash in Al-Si products is discussed. After extracting and purifying the chemical components, the high value-added products are prepared according to the gradation of crystal form, particle size and specific surface area, which not only improve the market value of fly ash, but also improve the market value of fly ash. And is advantageous to the environment ecology civilization construction. In this paper, based on the previous research, the aluminum and silicon products of fly ash are refined and diversified, even functionalized. Through the design and study of the experiment, the optimized technological conditions are as follows: (1) the fly ash and Na2C03 are mixed at 1: 0.9 ratio of ash to alkali, roasted at 875 鈩，
本文编号：2399598
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