过氧化氢-硫酸氧化碘离子反应动力学研究

用准级数和初始反应速率方法对过氧化氢-硫酸氧化碘离子反应过程进行了研究.结果表明,溶液中无[SO2-4]存在时,总氧化反应表现为一级反应;系统中加入硫酸时,总氧化反应呈现零级反应特征.分析了硫酸的催化机理.氢离子浓度对该反应的作用较为复杂.研究结果对极低浓度碘原料的催化氧化回收有重要意义.     

富集含碘吸收液快速反应结晶实验研究

以贵州宏福实业开发有限总公司碘回收装置生产的富集含碘吸收液为原料,用自制的新型氧化剂A-21将富集含碘吸收液中碘离子氧化为单质碘结晶析出.为了避免对所用不锈钢材质设备的腐蚀及碘的升华损失,开发了新型氧化剂A-21,设计使用了专门的压力静态过滤器.在探索试验的基础上,用正交试验法考察了搅拌速率、氧化剂用量、反应时间、反应温度等各影响因素.研究结果表明,与传统的静置氧化工艺相比,快速反应结晶工艺使碘从富集含碘吸收液中析出的结晶时间由原来的6～10 d缩短到4 h以内,碘的回收率提高到99%以上,具有很高的工业应用价值.     

碘吸收液中碘离子催化氧化结晶研究

采用分步酸化法制备了CR207催化剂。考察CR207对反应速率、碘离子氧化率、双氧水的利用率的影响,研究CR207是否对碘离子造成过氧化。结果表明,当n(I-)∶n(H2O2)=2∶1,每0.023 mol碘离子中CR207用量为65 mg时,能够使双氧水氧化碘离子的速率提高30倍以上,10 min内氧化率提高2.73倍,反应终点时间由原来的51 h缩短至2 h。在催化双氧水氧化碘离子时CR207没有造成过氧化现象。     

氟硅酸中碘回收工艺氧化条件研究

以含碘98mg/L的氟硅酸为原料,以10mmol/L的双氧水为氧化剂,考察了氧化剂加入量、反应时间、反应温度对碘的氧化率的影响。通过实验获得碘的氧化条件为:双氧水加入量为碘离子物质的量量的0. 51倍,反应时间为30min,反应温度为50℃。     

碘酸钙制备方法

介绍了以单质碘为原料,在盐酸存在下经氯酸钾氧化,氢氧化钾中和,再与氯化钙进行复分解反应制备碘酸钙的方法,本法具有反应条件温和,设备简单,操作方便,收率较高的特点。     

孔雀绿褪色光度法测定碘

在稀Hel介质中,Ⅰ-可催化KIO4氧化孔雀绿的褪色反应,且褪色程度与Ⅰ-浓度成正比,由此建立了测定痕量Ⅰ-的新方法,确定了最佳反应条件.测定碘的线性范围是0.5～5.0mg·L-1;检出限为0.3mg·L-1.方法简便、准确,用于食盐中碘的测定,结果满意.     

季铵盐型二醋酸碘苯的合成及其氧化反应研究

以对碘苯甲醛为起始原料,经还原、卤代、季铵化、氧化反应,成功合成了具有季铵盐结构的二醋酸碘苯,考察了这种新型的二醋酸碘苯对醇的氧化反应,这种二醋酸碘苯的合成简单,反应条件温和,收率较高,对醇的氧化具有产率高,条件温和,选择性较好等优点。     

醋酸与磷钨钼酸混合溶剂中甲烷部分氧化研究

采用单因素考察法考察了以碘为催化剂,在醋酸和磷钨钼酸混合溶剂中各种工艺条件对甲烷液相部分催化氧化反应的影响。磷钨钼酸与醋酸的混合溶剂体系可用于甲烷部分氧化反应,以碘为催化剂有较好的催化效果。通过对液相产物的分析,提出了在醋酸与磷钨钼酸混合溶剂中甲烷液相部分氧化反应属于亲电取代反应机理。反应条件为碘催化剂浓度0.04 mol/L,混合溶剂中醋酸50 mL,磷钨钼酸0.14 mol/L,氧化剂K2S2O80.20 mol/L,温度210℃,压力4.0 MPa时,甲烷转化率可达32.79%,目的产物选择性可达96.64%。     

从工业废液中提取碘的研究

本文介绍了用氧化蒸馏法从废液中提取碘的研究。确定了氧化、酸化等操作的最佳条件及氧化剂的配方,为生产提供了有用的数据。     

IBX在有机合成中的应用研究进展

对高价碘化合物邻碘酰苯甲酸（IBX）用于有机合成反应，如氧化、加成、取代和重排的最新研究进展进行了概述。     

碘酸钙废液利用的研究

研究了利用碘酸钙废液回收氯化钾、碘酸钙和碘的工艺技术。其主要成分氯化钾,经浓缩、除杂质离子、还原、树脂交换回收碘、精制等工艺过程得到了高度提纯。应用本工艺既消除了废水污染,也提高了产品的综合经济效益。     

OPTIMIZATION OF PARAMETERS FOR THE SYNTHESIS OF SILVER IODATE SUBMICRON BELTS BY TAGUCHI ROBUST DESIGN METHOD

A statistical experimental design method was implemented to optimize experimental conditions for the preparation of silver iodate fine belts using precipitation method. Ultrafine silver iodate belts were synthesized by addition of silver ion solution to the iodate reagent. The optimal conditions were determined using the Taguchi method. The effect of reaction conditions such as silver and iodate concentrations, flow rate of reagent addition, and temperature on the diameter of synthesized silver iodate belts were investigated. The results for analysis of variance (ANOVA) showed that silver iodate submicron belts can be synthesized by controlling silver concentration, flow rate, and temperature. Finally, the optimum conditions for synthesis of silver iodate submicron belts by this simple and fast method were proposed. The results of ANOVA showed that 0.001 mol/L silver ion concentration, 10 mL/min flow rate for addition of iodate reagent to the solution, and 0°C temperature are optimum conditions for producing silver iodate submicron belts with 228 ± 32 nm width.     

Alumina fiber-reinforced silica matrix composites with improved mechanical properties prepared by a novel DCC-HVCI method

A novel direct coagulation casting via controlled release of high valence counter ions (DCC-HVCI) method was applied to prepare the alumina fiber-reinforced silica matrix composites with improved mechanical properties. In this method, the silica suspension could be rapidly coagulated via controlled release of calcium ions from calcium iodate and pH shift by hydrolysis of glycerol diacetate (GDA) at an elevated temperature. The influence of tetramethylammonium hydroxide (TMAOH) dispersant amount, volume fraction and calcium iodate concentration on the rheological properties of suspensions was investigated. Additionally, the effect of alumina fiber contents on the mechanical properties of alumina fiber-reinforced silica matrix composites was studied systematically. It was found that the stable suspension of 50 vol% solid loading could be prepared by adding 2.5 wt% TMAOH at room temperature. The addition of 0–15 wt% alumina fibers had no obvious effect on the viscosity of the silica suspension. The controlled coagulation of the suspension could be achieved by adding 6.5 g L⁻¹ calcium iodate and 1.0 wt% GDA after treating at 70 °C for 30 min. Compressive strength of green bodies with homogeneous microstructure was in the range of 2.1–3.1 MPa. Due to the fiber pull-out and fracture behaviors, the mechanical properties of alumina fiber-reinforced composites improved remarkably. The flexural strength of the composite with 10 wt% alumina fibers sintered at 1350 °C was about 7 times of that without fibers. The results indicate that this approach could provide a promising route to prepare complex-shaped fiber-reinforced ceramic matrix composites with uniform microstructure and high mechanical properties.     

碘酸钾对电镀铬过程的作用

本文研究了碘酸钾对镀铬阴极过程的影响。加入碘酸钾后，可使含有机添加剂的镀铬溶液稳定性最高，并使阴极电流效率及沉积速度提高。同时使镀液的覆盖能力和分散能力得到改善。测定了加入碘酸钾前后的镀铬阴极化曲线，利用ＸＰＳ方法对镀层表面及深度分析表明，碘酸钾不与铬发生共沉积。     

电解法制备食品级碘酸钾

用直接电氧化法合成食品级碘酸钾,并进行了放大实验.最佳工艺条件下,碘酸钾总产率为97.5%,纯度为100.2%,电效率为97%.整个制备过程工艺简单,无污物排放.     

Catalytic-oxidation of Janus green in the presence of AgNPs: Application to the determination of iodate

Catalytic-oxidation of Janus green was made in the presence of AgNPs. The reaction was monitored spectrophotometrically at 610 nm. The system was optimized for the trace analysis of iodate. The method is featured with good accuracy and reproducibility for iodate monitoring in real samples without any pre-concentration and separation step.     

碘酸钾滴定法测定阳极泥中锡含量

主要对碘酸钾滴定法测定阳极泥中锡的含量的操作条件进行了试验。通过对试样的分解、铁粉、铝粒及淀粉溶液的用量进行了试验研究,并对其中影响测定锡的杂质元素进行了分离。用代表样加锡标准考查方法的准确度及精密度,样品加标回收率在99.2%～100.2%之间,精密度和准确度较好。该测定方法终点易观察,测定结果稳定准确,适用于测定阳极泥中10%以上的锡含量。     

碘酸钾、高碘酸钾、重铬酸钾混合体系中各含量的测定

介绍了含KIO4、KIO3、K2Cr2O7混合溶液的各自含量的测定的方法,该方法操作简便,有较高的精密度和准确度,适用于含多种氧化物质中各组分含量的测定。     

加碘食盐现场快速半定量检测液的研制

1 引言 碘是人体必需的微量元素,缺碘将会引起一系列碘缺乏病。为消除碘缺乏病,目前,我国大部分缺碘地区采用在食盐中加碘酸钾和碘化钾的方法。因此,食盐中碘含量便成为评价食盐是否合格的一个重要指标。测定加碘盐中的碘含量,以往的文献中有容量滴定法,主要用于食盐中碘酸钾含量测     

Villermaux-Dushman protocol for experimental characterization of micromixers

The iodide/iodate chemical test reaction (named Villermaux-Dushman method) initially proposed to characterize micromixing in conventional stirred tank reactors has become an extensive method to characterize continuous micromixers. Several protocols have been proposed and adapted to very efficient devices, but misunderstanding makes the use of this chemical test somewhat difficult which can lead to erroneous results. Furthermore, many papers only present the segregation index which is very dependent of the concentration set when mixing time, a concentration-free feature, should be preferred to compare micromixers. This paper presents the detailed protocol of the iodide/iodate test method, with different concentration sets and a general protocol to determine mixing times in micromixers.