【摘要】：作為對環(huán)境影響極大的粉狀固體工業(yè)廢物—粉煤灰,對土地、水質(zhì)、空氣都有不同程度的污染,對人類的生產(chǎn)和生活均十分不利。故探討粉煤灰在鋁硅產(chǎn)品方面的精細(xì)化利用,其中化學(xué)成分提取純化后,按晶型、粒徑、比表面積等分級制備高附加值的產(chǎn)品,不但提高了粉煤灰的市場價(jià)值,而且有利于環(huán)境生態(tài)文明建設(shè)。本文在課題組前人的研究基礎(chǔ)上,實(shí)現(xiàn)粉煤灰的鋁硅產(chǎn)品的精細(xì)化和多元化,甚至功能化。通過實(shí)驗(yàn)的設(shè)計(jì)和研究,工藝條件的優(yōu)化結(jié)果如下:(1)粉煤灰與Na2C03按灰堿比為1:0.9研磨混勻,875 ℃焙燒活化2h,加入濃度為3mol/L 的H2SO4將焙燒物酸浸后過濾,濾渣作制備硅產(chǎn)品備用,濾液經(jīng)結(jié)晶和重結(jié)晶提純,烘干制備Al2(SO4)3產(chǎn)品;利用NH3·H2O與Al2(O4)3產(chǎn)品反應(yīng),過濾后干燥生產(chǎn)Al(OH)3產(chǎn)品。(2)將A12(SO4)3產(chǎn)品與Na2CO3按鋁鈉比1:3.5攪拌混溶均勻,同時(shí)水浴加熱進(jìn)行反應(yīng),制備中間產(chǎn)物勃姆石(即鋁的水合氧化物,化學(xué)式為Al2O3·nH20)。此段反應(yīng)的最佳工藝條件為:水浴反應(yīng)溫度為60℃;反應(yīng)時(shí)間為30min。(3)在A1203前軀體焙燒時(shí),為實(shí)現(xiàn)完全的晶型轉(zhuǎn)化和制備較純的氧化鋁晶型,并制備出合適的納米級產(chǎn)品,選取600℃的焙燒溫度,效果較佳。(4)焙燒活化及酸浸后的濾渣1,再次經(jīng)熱堿浸過濾提純,此時(shí)得濾渣2返回至濾渣1,循環(huán)利用,濾液中加H2SO4制酸溶膠。最佳的工藝為:制酸溶膠的H2SO4濃度為3.0mol/L;此時(shí)產(chǎn)品的比表面積和DBP吸收值均較大;(5)硅酸溶膠制備超細(xì)白炭黑時(shí),為限制晶粒的團(tuán)聚,需加入復(fù)合分散劑,從而制備粒徑更小的白炭黑。最佳工藝參數(shù)為:粉煤灰與復(fù)合分散劑的比值為0.10%,反應(yīng)溫度為60℃,反應(yīng)時(shí)間為35min,制得結(jié)構(gòu)組成中具有輕基結(jié)構(gòu)水的SiO2產(chǎn)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，

本文編號：2399598