间接碘量法测定高铁酸钾

提出了间接碘量法测定高铁酸钾样品中常量、高含量高铁酸钾的方法。用碱性碘化钾溶液(pH 11～12)溶解高铁酸钾试样,调节溶液的pH值为1,反应40min后,以硫代硫酸钠标准溶液作为滴定剂进行滴定。方法用于高铁酸钾样品的分析,测定结果与亚铬酸盐法测定值相符。     

相转移催化下复合高铁酸钾氧化甲苯的研究

制备了高稳定性的复合高铁酸钾氧化剂,并进行了表征.研究了高铁酸钾溶液的pH值和浓度对高铁酸钾稳定性的影响,并确定了高铁酸钾稳定存在的溶液环境.以复合高铁酸钾为氧化剂,采用相转移催化氧化甲苯法合成苯甲酸.考察了相转移催化剂种类、催化剂用量、反应时间以及反应温度等因素对苯甲酸收率的影响.结果表明,以十六烷基三甲基溴化铵作相...     

基于次氯酸钙的高铁酸钾制备与表征

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%。     

高铁酸钾的合成与电化学性能研究

本文主要研究了锂离子电池正极材料高铁酸钾的合成,表征和电化学性质.用次氯酸钾与硝酸铁于碱性介质中反应得到高铁酸钾粗品,重结晶后成纯度大于97%的产品,用XRD和FTIR等方法对高铁酸钾进行表征和分析.初步研究了K2FeO4/Li电池的充放电性能.     

高铁酸钾的制备及其在废水治理中的应用进展

高铁酸钾是一种集氧化、絮凝、吸附、杀菌、消毒、除臭功能于一体的新型绿色高效水处理药剂,在废水处理领域具有重要的理论研究和实际应用价值。本文对近年来高铁酸钾的制备方法及其在废水治理中的应用进行综述,重点分析了各制备方法的优缺点,并结合当前最新研究成果对高铁酸钾的工业制备及在废水治理中的应用前景进行了展望。     

用绿色氧化剂高铁酸钾相转移催化氧化苯甲醇

采用改进的次氯酸盐氧化法合成了高铁酸钾氧化剂,并进行了表征。研究了相转移溶剂存在下高铁酸钾氧化苯甲醇合成苯甲醛的反应,考察了有机溶剂及相转移溶剂对反应选择性和产率的影响。环己烷和pH=11·5的氢氧化钠水溶液作溶剂,在苄基三甲基氯化铵相转移溶剂存在下,室温(18℃)反应7min时,高铁酸钾氧化苯甲醇制苯甲醛反应的选择性及产率分别为97·2%和89·1%。     

高铁酸钾与饮用水处理

介绍了高铁酸钾的制备、性质以及在饮用水处理方面的应用。     

重要更正

本刊今年第2期发表的高铁酸钾去除微污染水源中氰化物的试验研究一文出现严重错误,其中第181页的图5与图6在排版时发生错排,现予更正为:     

高铁酸钾热分解的研究

本文采用差热热重仪、穆斯堡尔谱仪、X射线光电子能谱仪和X射线衍射仪等分析仪器,研究了高铁酸钾的热分解过程,提出热分解产物可能形成固熔体的看法。     

高铁酸钾电化学性能研究

主要研究正极材料高铁酸钾的合成以及用它作为正极活性物质在一次性碱性电池中 ,于不同浓度电解质溶液和不同放电电流下的放电性能 .发现其在 9mol/L- 1KOH溶液中放电容量最高 ,并表现出良好的放电平台特性 .0 .4C时 ,放电容量可达 5 2 1 .3mAh/ g .XRD分析表明 ,放电后产物为Fe3O4 ,由此提出相关可能的放电反应机理     

Studies on the Electrochemical Characteristics of K2FeO4 Electrode

Discharge performance of K2FeO4 electrode under different conditions was studied by the constant electric current discharge method. The electrochemical characteristics of K2FeO4 electrode were investigated for the first time by means of cyclic voltammetry. The results show that the K2FeO4 electrode made at moderate pressure (20MPa) and discharged at lower current has better discharge performance. It is also found that K2FeO4 electrode is significantly rechargeable.     

电解法制备K_2FeO_4过程添加剂的筛选

应用电解法,并于阳极电解液中分别加入KIO4等不同种类添加剂制备K2FeO4,考察添加剂对电流效率以及FeO42-稳定性的影响规律,产品K2FeO4的结构形貌由XRD、SEM表征.结果表明,KIO4是比较理想的添加剂,在阳极液中添加质量比为0.02%的KIO4,电解1h后,电流效率可提高31.6%,K2FeO4产品的纯度相应提高了3.85%.     

K2FeO4-Zn碱性固态电解质电池电化学性能研究

应用溶液铸膜法制备出了交联聚乙烯醇(PVA)/聚丙烯酸(PAA)-KOH-H2O复合碱性固态电解质膜, 其厚度为150 µm左右, SEM测试结果表明其表面呈均相的非晶态结构, 交流阻抗(EIS)测试表明室温离子电导率可达3.5×10－2 S• cm－1, 循环伏安(CV)测试表明其电化学稳定窗口为3.5 V左右, 将其应用于一次碱性K2FeO4-Zn电池, 通过研究固态电解质膜在不同浓度KOH碱液中预处理和其在不同放电倍率下的放电性能, 结果表明, 9 mol•L－1为最佳固态电解质膜预处理碱液浓度, 0.4 C为最佳放电倍率, 1.0 V以上容量最高可达222.6 mAh•g－1, 并表现出良好的放电平台特性.     

Sorption of selenite ions on hematite

The sorption of selenite from aqueous solutions onto hematite was investigated as a function of pH (2-12), ionic strength (0.01-0.1 M), and concentration of selenium (10(-7)-10(-2) M). The sorption may proceed according to two processes: surface complexation, followed by the precipitation of ferric selenite starting at approximate [Se] = 4 x 10(-4) M (surface coverage>ca. 2 at nm(-2)). The sorption isotherms have been fitted by a Tempkin equation. A surface complexation model (2-pK/Constant Capacitance Model) was used to fit the sorption data. The nature of the surface species of selenite cannot be determined by modeling since monodentate >FeOSe(O)O- or >FeOSe(O)OH and bidentate (>FeO)2SeO surface complexes are both able to fit the experimental data. The reversibility and kinetics of sorption were also studied. The affinity of selenite ions toward hematite, expressed as the distribution coefficient with respect to the surface area (K(D) in L m(-2)), was compared with results published for other ferric oxides (goethite and amorphous ferric oxide). It was found that the reactivity toward selenite is similar, contrary to acid-base properties which depend on the nature of the oxide and its level of purity.     

四水二异烟酸锌(Ⅱ)的合成及其晶体结构

在水热条件下,吡啶-4-甲醛与Zn(ClO4)·6H2O反应合成了标题化合物[Zn(C6H4O2N)2(H2O)4].在193 K,用单晶X-射线衍射法对该化合物重新进行了结构表征,得到更高精确度的数据.该化合物分子是中心对称.     

Mössbauer characterization and in situ monitoring of thermal decomposition of potassium ferrate(VI), K2FeO4 in static air conditions

Solid orthorhombic crystals of potassium ferrate(VI) (K(2)FeO(4)) of a high-chemical purity (>99.0%) were characterized by low-temperature (1.5-5 K), high-temperature (463-863 K), and in-field (1.5 K/3 T) M?ssbauer spectroscopy. Potassium ferrate(VI) reveals a Néel magnetic transition temperature (TN) of approximately 3.8 K and a saturation hyperfine magnetic field of 13.8 T at 1.5 K. Spectral line intensities recorded below TN in an external magnetic field of 3 T manifest a perfect antiferromagnetic ordering. For the in situ monitoring of the thermal behavior of K(2)FeO(4), high-temperature M?ssbauer data were combined with those obtained from thermogravimetry, differential scanning calorimetry, and variable-temperature X-ray diffraction measurements. Such in situ approach allowed the identification of the reaction products and intermediates and yielded the first experimental evidence for the participation of CO2 in the decomposition process. As the primary conversion products, KFeO(2) and two potassium oxides in equivalent molar ratio, KO2 and K(2)O, were suggested. However, the KO2 phase is detectable with difficulty as it reacts very quickly with CO2 from air resulting in the formation of K(2)CO(3). The presented decomposition model is consistent with thermogravimetric data giving the mass loss of 8.0%, which corresponds to the participation of 1/6 mol of CO2 and liberation of 3/4 mol of O2 per 1 mol of K(2)FeO(4) (K(2)FeO(4) + 1/6CO2 --> KFeO(2) + 1/3K(2)O + 1/6K(2)CO(3) + 3/4O2). An explanation of the multistage reaction mechanism has an important practical impact for the optimization of the solid-state synthesis of potassium ferrate(VI).     

高铁酸钾氧化脱除模拟轻质油中的含硫化合物

考察了K2FeO4对模拟轻质油中苯并噻吩（BT）及二苯并噻吩（DBT）的氧化性能。结果表明，水相中K2FeO4对BT、DBT的氧化活性比较低，水的存在使K2FeO4水解成黄色的Fe(OH)3而失去氧化有机硫化物的能力；在冰乙酸反应介质中，K2FeO4对BT及DBT的氧化活性有了明显的提高；固体催化剂KM的加入显著提高了乙酸反应介质中K2FeO4对BT及DBT的氧化活性。常温、常压，醋酸/模拟油体积比为1.0，K2FeO4/S摩尔比为1.0，KM/K2FeO4质量比为1.0的条件下，DBT的转化率达98.4%，BT的转化率为70.1%。     

锌铬水滑石的合成及表征

采用共沉淀法合成了一系列不同Zn/Cr摩尔投料比的碳酸根型水滑石。用X－衍射、红外光谱、差热、热重、分光光度等方法对其组成和结构进行了研究。结果表明Zn/Cr摩尔投料比为2和3时都能形成结晶度好、纯度高的水滑石。其它摩尔投料比产物中都不同程度的含有一些杂质。所有水滑石均有两个吸热失重热分解过程。产物中总的Zn/Cr摩尔比和摩尔投料比、产物纯度有关系。