硫酸盐黑液直接苛化循环试验研究

Direct Causticization between Recycled Titanates and Black Liquor

采用管式炉在820～850℃的温度范围内对硫酸盐黑液在水蒸气气化条件下进行了若干次直接苛化循环试验,反应所得钛酸盐在100℃的条件下水解20min,用化学方法分析水解溶液成分,用X射线衍射仪(XRD)和电感耦合等离子体发射光谱仪(ICP)分别分析所得一系列钛酸盐的晶形和Ti/Na2比。结果表明:高温反应得到以4Na2O.5TiO2为主的钛酸盐,水解得到Na2O.3TiO2和Na2O.6TiO2。总体碳酸钠转化率最后达75%以上;气化后残留10%左右的硫酸盐。

The direct causticizing reaction between recycled titanates and black liquor was carried out under 820 -850℃ in tubular furnace with steam gasification. The gasified titanates were hydrolyzed in 100℃ boiling water. Solution composition was analyzed in chemistry way and all the titanates in solids were analyzed in X -ray diffraction （XRD） and Inductive Coupled Plasma Emission Spectrometer （ICP） to identify the crystal form and the Ti/Na2 mole ratio. The results show that the gasified titanates are mainly made up of 4Na2O . 5TiO2 and the hydrolyzed titanates contain Na2O. 3TiO2 and Na2O - 6TiO2. The NaOH form hydrolyzation increases with the recycle number. The conversion of sodium carbonate finally reached over 75%. About 10% sulphate remained in the gasified solids.