钛渣硫酸铵焙烧法提钛渣提硅试验研究

Experimental Research on Extracting Silicon from the Residue of Roasting the Titania Slag by(NH_4)_2SO_4

采用硫酸铵焙烧法从钛渣中提钛后得到大量的滤渣,主要含有二氧化硅和氧化钙。将滤渣和氢氧化钠溶液混合均匀加热搅拌,抽滤后得到硅酸钠溶液,最佳工艺条件:NaOH与滤渣质量比3.5︰1、反应温度210℃、液固比5:1、反应时间80 min;将硅酸钠溶液加入氧化钙加热搅拌,在110℃时反应60 min过滤分离,得到硅酸钙沉淀,同时得到氢氧化钠溶液。

A large number of the residue was obtained after extracting titanium by（NH_4）_2SO_4 roasting from the titania slag. The residue consisted mainly of silicon dioxide and calcium oxide. The residue and sodium hydroxide solution were mixed uniform and stirred under the constant temperature and then filtrated to obtain the sodium silicate solution. The optimum operating conditions were obtained as mass ratio of sodium hydroxide to the residue of 3.5：1, reaction temperature of 210℃, liquid-solid ratio of 5：1 and reaction time of 80 min. The sodium silicate solution and calcium oxide were mixed and stirred under the conditions of the temperature of 110 ℃ and reaction time of 60 min. CaSiO_3 and NaOH solutionh were obtained through filtration.