盐酸电解工艺及概况

简述了盐酸电解生产氯的发展历史、生产工艺,并对盐酸电解与氯碱电解进行了比较。

Role of Sb(V) in removal of As, Sb and Bi impurities from copper electrolyte

The function mechanism of Sb（V） in As, Sb and Bi impurities removal from copper electrolyte was investigated by adding Sb（V） ion in a synthetic copper electrolyte containing 45 g/L Cu2＋, 185 g/L H2SO4, 10 g/L As and 0.5 g/L Bi. The electrolyte was filtered, and the precipitate structure, morphology and composition were characterized by chemical analysis, SEM, TEM, EDS, XRD and FTIR. The results show that the precipitate is in the shape of many irregular lumps with size of 50-200 μm, and it mainly consists of As, Sb, Bi and O elements. The main characteristic bands in the FTIR spectra of the precipitate are As-O-As, As-O-Sb, Sb-O-Bi, Sb-O-Sb and Bi-O-Bi. The precipitate is the mixture of microcrystalline of AsSbO4, BiSbO4 and Bi3SbO7 by XRD and electronic diffraction. The removal of As, Sb and Bi impurities by Sb（V） ion can be mainly ascribed to the formation of antimonate in copper electrolytes.

铝及铝合金电刷镀银

通过盐酸电解浸蚀法及电刷镀铜过渡 ,实现铝及铝合金上电刷镀银 ,确定铝及铝合金电刷镀银的一种刷镀工艺 ,提高了镀层耐腐蚀强度 ,得到了外观和结合力均良好的银镀层 ,同时增加镀铜层厚度 ,相对减少镀银层厚度 ,不影响其它指标 ,节省了镀银药液 ,降低了成本 。

强酸强碱形成的移动中和反应界面的实验研究

介绍一种用于等电聚焦电泳 (IEF)以及移动中和化学反应界面 (MCRB)的实验方法 ,并优化实验方法和条件 .利用优化的方法和实验条件 ,完成了由强电解质盐酸和氢氧化钠形成的MNRB实验 .实验结果与MCRB理论定量吻合 .这一实验方法对于IEF和MNRB的研究具有重要的意义 .

Influence of anions in phosphate and tetraborate electrolytes on growth kinetics of microarc oxidation coatings on Ti6Al4V alloy

The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and potentiodynamic polarization.The results showed that B_(4)O_(7)^(2−)increased the spark intensity and dissolved most of the oxides at high temperatures.Then,a thicker barrier layer at the coating/substrate interface was produced,which increased the polarization resistance of the coating.PO_(4)^(3−)at a low concentration also promoted the uniform growth of the MAO coating and the formation of hat-shaped holes in the outer deposition layer.The thickness of the MAO coatings obtained in Na_(2)B_(4)O_(7) electrolytes exhibited an exponential increase with time at spark discharge stage,while that of the MAO coating obtained in phosphate–tetraborate electrolytes showed a linear trend as the PO_(4)^(3−)content increased.

Structure characterization and electrochemical properties of new lithium salt LiODFB for electrolyte of lithium ion batteries

Lithium difluoro(axalato)borate (LiODFB) was synthesized in dimethyl carbonate (DMC) solvent and purified by the method of solventing-out crystallization. The structure characterization of the purified LiODFB was performed by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR) spectrometry. The electrochemical properties of the cells using 1 mol/L LiPF6 and 1 mol/L LiODFB in ethylene carbonate (EC)/DMC were investigated, respectively. The results indicate that LiODFB can be reduced at about 1.5 V and form a robust protective solid electrolyte interface (SEI) film on the graphite surface in the first cycle. The graphite/LiNi1/3Mn1/3Co1/3O2 cells with LiODFB-based electrolyte have very good capacity retention at 55 ℃, and show very good rate capability at 0.5C and 1C charge/discharge rate. Therefore, as a new salt, LiODFB is a most promising alternative lithium salt to replace LiPF6 for lithium ion battery electrolytes in the future.

Exchange Reaction Between Selenite and Hydroxyl Ion of Variable Charge Soil Surfaces: I. Electrolyte Species and pH Effects

Hydroxyl release of red soil and latosol surfaces was quantitatively measuredusing a self-made constant pH automated titration instrument, to study the changes of hydroxylrelease with different added selenite amounts and pH levels, and to study the effects ofelectrolytes on hydroxyl release. Hydroxyl release increased with the selenite concentration, with arapid increase at a low selenite concentration while slowing down at a high concentration. The pHwhere maximum of hydroxyl release appeared was not constant, shifting to a lower valus withincreasing selenite concentration. Hydroxyl release decreased with increasing electrolyteconcentration, and the decrease was very rapid at a low electrolyte concentration but slow at a highelectrolyte concentration. For NaClO_4, NaCl and Na_2SO_4, hydroxyl release was in the order ofNaClO_4 > NaCl >> Na_2SO_4, and the difference was very significant. But for NaCl, KCl and CaCl_2,the order of hydroxyl release was NaCl > KCl > CaCl_2, and the difference was smaller. The amount ofhydroxyl release from Xuwen latosol was greater than that from Jinxian red soil. Hydroxyl releaseexisted in a wider range of pH with Xuwen latosol than with Jinxian red soil, due to theirdifference in soil properties. However, both soils had similar curves of hydroxyl release,indicating the common characteristics of variable charge soils.

Electrolytic Regeneration of Decarbonising Potassium Carbonate Solution

In this work,the regeneration mechanism of potassium carbonate solution after absorption of CO2 using ion-exchange membrane electrolysis was presented.The solutions of potassium carbonate(K2CO3) and potassium bicarbonate(KHCO3) were used to simulate the solution after absorbing CO2.Experiments were carried out at various electrodes,temperatures and current densities.The results indicate that the membrane electrolysis can in-crease concentration ratio of K2CO3 and KHCO3,and achieve 100%conversion.In this process,not only CO2 is desorbed from carbonate solution,but also hydrogen,as a byproduct,is generated at the cathode,which is the main contributor to reduce energy consumption.Thus,the membrane electrolysis is valuable in the regeneration of the K2CO3 absorbent.

P Fractions in Drainage Waters from the Broadbalk Continuous Wheat Experiment at Rothamsted

Total P (TP), total participate P (PP), total dissolved P (TDP), molybdatereactive P (MRP) and dissolved organic P (DOP) were determined in waters from pipe-drains (at 65-cmdepth) from the Broadbalk Experiment at Rothamsted Research, UK. Average TPand PP exceeded 1 mgL^(-1) in about half of the 12 plots receiving superphosphate for the 5 measurements taken betweenDecember 2000 and April 2001. Ranging between 33.8% and 87.3% of TP, PP was the largest P fractionin drainage waters, with DOP, ranging from 0.5% to 26.2% of TP, being the smallest fraction Meanproportions of PP, MRP and DOP in TP in drainage waters were 63.4%, 32.5% and 4.1%, respectively.These findings support previous findings that P losses from soil to drainage waters were muchlargerthan previously thought, and could therefore make a significant contribution to eutrophication.

Effects of Organic Anions on Phosphate Adsorption and Desorption from Variable-Charge Clay Minerals and Soil

Effects of citrate and tartrate on phosphate adsorption and desorption from kaolinite, goethite, amorphous Al-oxide and Ultisol were studied. P adsorption was significantly decreased as the concentration of the organic anions increased from 10-5 to 10-1 M. At 0.1 M and pH 7.0, tartrate decreased P adsorption by 27.6% - 50.6% and citrate by 37.9 - 80.4%, depending on the kinds of adsorbent. Little Al and/ or Fe were detected in the equilibrium solutions, even at the highest concentration of the organic anions. Effects of the organic anions on phosphate adsorption follow essentially the competitive adsorption mechanism.The selectivity coefficients for competitive adsorption can be used to compare the effectiveness of different organic anions in reducing P adsorption under given conditions.Phosphate desorption was increased by 3 to 100 times in the presence of 0.001 M citrate or tartrate compared to that in 0.02 M KC1 solution alone. However, for all the soil and clay minerals studied the amount of P desorbed by citrate or tartrate was generally lower than or close to that of isotopically exchangeable P. The effect of organic anions on phosphate desorption arises primarily from ligand exchange.

Synthesis and physico-chemical properties of new green electrolyte 1-butyl-3-methylimidazolium perchlorate

1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as electrochemical window,were investigated and solvent performance was also studied.The results show that this kind of ionic liquid is an excellent electrolyte with low viscosity,high electrical conductivity and wide electrochemical window.In addition,[BMIM]ClO4 is soluble in most conventional solvents and some metal oxides have high solubility in it,which lays the foundation of direct electrolysis of metal oxides in this ionic liquid.

A Facile Surface Passivation of Hematite Photoanodes with Molybdate Overlayers for Efficient PEC Water Oxidation

α-Fe2O3 thin films have been synthesized and used as photoanodes for photo-electrochemical (PEC) water oxidation. Molybdate was introduced to mediate hematite thin films via two synthesis routes (namely in situin situ mediation and ex situ modification). Through the in situ mediation process, the morphology and film thickness could be changed significantly due to the addition of MoO42-, while for the ex situ modification, the PEC performance of the hematite has been greatly improved without changing the nanorod morphology. Various characterizations such as UV-Vis absorption, transmission electronic microscopy, scanning electronic microscopy, Mott-Schottky, electrochemical impedance spectroscopy were conducted and the PEC performances were investigated.

Stability of [BMIM]HSO_4 for using as additive during zinc electrowinning from acidic sulfate solution

The stability of ionic liquid additive 1-butyl-3-methylimidazolium hydrogen sulfate （[BMIM]HSO4） during zinc electrowinning from acidic sulfate solution was investigated by cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. Compared with the traditional industrial additives, gelatine and gum arabic, [BMIM]HSO4 has more excellent chemical and thermal stabilities. The inhibition effects of gelatine and gum arabic on the zinc electrocrystallization are observed to markedly weaken due to their part degradation after 12 h longtime successive electrolysis and high temperature （90 ℃） treatments. In contrast, the activity of [BMIM]HSO4 is practically unaffected after 24 h longtime successive electrolysis and high temperature treatments. These results are corroborated with the corresponding morphological analysis of the cathodic deposits.

工业废盐酸的动态离子交换法除铝研究

采用001×7型阳离子树脂对电解工段的废盐酸进行了脱除铝的研究。通过动态吸附实验考察了废盐酸处理量以及树脂床高径比对铝吸附效果的影响,确立了树脂床的最佳工作条件。结果显示,最佳进料流量为0.2 mL/s,树脂床的高径比为10:1,贯穿时间为10.3min,贯穿吸附容量为760 mg,接触时间τ为43.3 min时树脂床饱和需再生,此时铝的去除率为52.3%,饱和吸附容量为1409 mg。