以硫酸浸出粉煤灰中的铝、铁离子,以碱为沉淀剂,根据铝、铁离子水解pH差异沉淀出氢氧化铁前驱物,经煅烧制备氧化铁颜料,并探究酸浸温度、pH区间以及煅烧温度对氧化铁颜料提取率的影响。利用X射线衍射(XRD)等表征手段对其物相组成进行表征。结果表明,在酸浸温度为150℃、时间为4 h的优化工艺条件下,酸浸铝铁的效果最佳;在pH为5时沉淀效果最佳,沉淀率可达98%;煅烧温度为550℃、时间为4 h时,其氧化铁产率可达98%。在优化条件下,氧化铁颜料产率可达98%,纯度可达97%。

Through the reduction and separation methods,aluminum and iron ions are leached from fly ash by sulfuric acid.Taking alkali as precipitant,the precursor of ferric hydroxide is precipitated according to the pH difference of aluminum and iron ions hydrolysis.Iron oxide pigment is prepared through the calcination of the precursor.The influence of acid leaching temperature,pH range and calcination temperature on the extraction rate of iron oxide pigment is explored.The phase composition of samples is characterized by means of X-ray diffraction (XRD),etc.It is shown that leaching aluminum and iron by acid achieves the best effect under the optimum conditions that the temperature and time of acid leaching is 150℃ and 4 h,respectively.At a pH of 5,the precipitation effect is the best,and the precipitation rate can reach 98%.The yield of ferric oxide can reach 98% when the calcination temperature is 550℃ and the calcination time is 4 h.Under the optimized conditions,the yield and purity of ferric oxide pigment can reach 98% and 97%,respectively.

齐雅楠(1997-),女,硕士研究生,主要从事无机膜分离技术及应用研究,458031702@qq.com