基于次氯酸钙的高铁酸钾制备与表征

Preparation and characterization of potassium ferrate based on calcium hypochlorite

为提高化学氧化法制备高铁酸钾的安全性,以次氯酸钙和碳酸钾反应制备碱性饱和次氯酸钾,继而氧化九水硝酸铁制备高铁酸钾。对制备条件进行了优化,结果表明次氯酸钾浓度1.15mol/L,反应时间60min,重结晶碱浓度15.48mol/L,正戊烷和无水乙醇交替洗涤除杂条件下所制备的高铁酸钾纯度较高。采用傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)以及紫外-可见吸收光度法对样品进行定性分析,证实所制备样品为高铁酸钾。采用邻菲罗呤分光光度法定量测定样品纯度,高铁酸钾含量大于97%。

To improve the security of chemical oxidation process of preparing potassium ferrate, alkaline potassium hypochlorite obtained by a reaction of calcium hypochlorite and potassium carbonate was used to oxidize the ferric nitrate to prepare potassium ferrate. The results indicated that the optimal conditions of ferrate preparation were given as below：the concentration of potassium hy- pochlorite at l. 15 molfL, reaction time at 60 min, reerystallization solution of alkali concentration at 15.48 mol/L, and n-pentane and absolute ethyl alcohol alternating washing. Fourier Transform Infrared（FT-IR） ,X-ray diffraction（XRD） and Ultraviolet and visible spectrophotometry were used to analysis ferrate samples and confirmed that these samples were potassium ferrate. The phenanthroline spectrophotometric method was used to determine the purity of samples, and the results showed that the purity of potassium ferrate was greater than 97%.