银硫代硫酸盐在活性炭上的吸附机理

研究了银硫代硫酸盐在活性炭上的吸附行为。考察了硫代硫酸钠和亚硫酸钠浓度、温度和溶液pH对活性炭吸附银硫代硫酸盐的影响,采用了多种动力学模型拟合吸附过程,并通过XPS和FT-IR检测手段对其机理进行表征。结果表明：银硫代硫酸盐在活性炭上的吸附动力学符合准二级动力学模型,活性炭对银硫代硫酸盐的吸附等温线符合Freundlich模型。银在活性炭的吸附容量随着温度的升高而略有下降。在下述最佳条件下：温度25 ℃、初始pH=8、初始银浓度500 mg/L、n(Na2S2O3)/n(AgNO3)=8(摩尔比)、n(Na2S2O3)/n(Na2SO3)=5(摩尔比)、吸附时间5 h,活性炭对银硫代硫酸盐络合物的饱和吸附容量最高可达18 mg/g。     

柠檬酸法脱硫中硫酸根的树脂吸附研究

采用静态法研究D301R、D301G、D370和D315四种弱碱性阴离子交换树脂吸附柠檬酸法脱除SO2的解吸贫液中硫酸根的效果,分析吸附时间、柠檬酸浓度、树脂用量、pH等对硫酸根吸附量的影响,解吸时间、解吸碱液浓度对树脂解吸效果的影响,及多次吸附解吸循环再生对树脂吸附活性的影响。结果表明,D315在高浓度柠檬酸钠溶液(1.0 mol/L)中对SO42-有较好的脱除效果,当氢氧化钠浓度为1.5mol/L时,3min即可将SO42-解吸完全,在经过10轮吸附解吸循环再生后其活性下降,吸附能力降低约15%。     

酒石酸盐-硫代硫酸盐协同浸金

采用酒石酸盐-硫代硫酸盐协同浸金体系，对某氧化型金矿开展了浸金试验研究，研究变量包括硫酸铜浓度、浸出时间、硫代硫酸钠和酒石酸钠浓度、溶液pH、温度等，确定了最佳浸出条件。结果表明，当硫酸铜、硫代硫酸钠、酒石酸钠的浓度分别为0.075、0.5、0.075 mol/L,浸出温度80℃,溶液pH为10.3,浸出时间9 h时，金浸出率可达96.03%。通过与氰化法和铜-氨-硫代硫酸盐体系的对比分析，铜-酒石酸盐-硫代硫酸盐体系浸金效果与氰化法相近，优于传统铜-氨-硫代硫酸盐提金体系。     

紫外光分解银硫代硫酸盐络合物的研究

银是一种贵金属,在自然界中少数以单质形式存在,多数以化合物形式存在于银矿石中。在含银的化合物中,硫化银(Ag2S)是一种化学稳定性高,窄能带半导体材料,具有较好的光电、热电性能,而被广泛用于光电池、光电导元件、红外检测器和快离子导体等领域。目前银矿石中银的提取往往采用氧化焙烧-硫酸浸出的方法,随着研究的深入近些年来已有学者提出一种全湿法流程,即研究利用无氨硫代硫酸盐体系在弱碱性条件下提取银矿石中的银,应用该方法会产生大量的含银硫代硫酸盐配合物溶液。为了有效回收利用银资源,同时结合硫代硫酸盐对紫外光敏感的性质,研究了在不同银浓度、不同硫代硫酸盐浓度、不同初始pH条件下银硫代硫酸盐配合物的分解过程,并对紫外光条件下的分解产物进行表征。实验结果表明,配合物可以在紫外光条件下发生分解生成硫化银沉淀从而实现银的回收。     

难处理铜金精矿硫代硫酸盐浸出试验

对东北某难处理铜金精矿进行了硫代硫酸盐浸出试验研究,考察了矿石预处理条件、浸出时间、液固比、硫代硫酸盐用量、氨水用量对矿石中金、银、铜浸出率的影响。结果表明,当磨矿细度-38 μm粒级占97%、矿浆浓度25%、吨矿硫代硫酸盐用量1.08 t、吨矿氨水用量0.35 t、常温摇瓶浸出24 h时,浸出尾渣中金、银、铜品位分别为3.04 g/t、63.2 g/t和12.16%,金、银、铜浸出率分别为92.43%、9.23%、6.68%。锌粉置换、活性碳吸附均不适用于硫代硫酸盐提金溶液的贵金属回收。     

几种螯合树脂在模拟的钴电解液中吸附铜的性能研究

对比研究了三种亚胺二乙酸螯合树脂D850、D463、D751、一种氨膦酸基螯合树脂D860及一种氨甲基吡啶树脂CuWRAM在模拟的钴电解液的硫酸盐体系、氯盐体系及硫酸盐-氯盐混合体系中吸附铜的性能.结果表明:五种树脂均在料液pH较高的条件下对铜的吸附容量最大,其中以D860的对铜的交换容量最大,以CuWRAM对铜的交换...     

D261大孔树脂吸附氰化物的性能及机理研究

研究了D261大孔树脂对氰化物的吸附性能及机理,考察了酸度、温度、溶液中氰化物质量浓度、时间及树脂用量对氰化物吸附的影响。试验结果表明,D261大孔树脂能有效地吸附简单氰化物和金、银、铜、锌、铁的氰络合物。热力学试验表明,吸附等温线符合Freundlich方程,吸附过程属于优惠吸附。动力学研究表明,吸附在室温下是瞬时反应,静态吸附过程主控步骤为Boyd液膜扩散,吸附的本质为物理吸附。同时,确定D261树脂的静态饱和吸附量为25.28mg/mL湿树脂。     

用氨性硫代硫酸盐从流纹岩矿石中浸出金和银

本研究工作确定了用含铜的氨性硫代硫酸盐溶液从矿石中溶解金和银的重要参数。通过绘制E_h-pH图分析了溶解过程的化学。试验结果表明,在1小时内可溶解出大约70％银和90％金。浸出过程对硫代硫酸盐和氨的浓度十分敏感,为了防止铜从溶液中沉淀为Cu_2S,从而避免银的损失,需要维持适当的E_h和pH条件。     

D301树脂吸附金的机理研究

本文利用XPS光电子能谱仪对D301树脂吸附金氰络合物前后的研究:确定此种吸附为离子吸附;D301树脂要达到较高的吸附量,必须先质子化;强的酸性环境可提高对Au(CN)_2~-的选择性,这一点在回收镀金废水中的金很有价值。     

季铵盐类离子液体萃取Au(S2O3)23-性能研究

硫代硫酸盐提金是一种绿色环保的非氰提金方法,但高效回收金浸出液中的金尚待进一步研究。以甲基三辛基氯化铵(TOMAC)为萃取剂,考察了萃取条件（萃取剂浓度、相比、萃取时间）及金浸出液性质（pH、硫代硫酸盐浓度、初始Au(I)浓度）对TOMAC萃取Au(Ⅰ)性能的影响。结果表明：室温条件下,TOMAC为萃取剂能从硫代硫酸盐金浸出液中高效萃取Au(Ⅰ)。当A/O=1、pH=9、硫代硫酸盐浓度0.1 mol/L、TOMAC浓度1.8 g/L时,对低浓度金(0~25 mg/L)几乎能完全萃取;采用1 mol/L NaCl能有效反萃出TOMAC有机相中的Au(Ⅰ)。TOMAC萃取Au(Ⅰ)的机制为：TOMAC通过其表面的Cl-与溶液中的Au(Ⅰ)发生离子交换,形成[C25H54N]3[Au(S2O3)2]络合物。TOMAC对Au(S2O3)23-具有良好的萃取性能,可实现硫代硫酸盐金浸出液中Au(I)的高效回收,具有对硫代硫酸提金技术的潜在应用价值。     

Evaluation of D113 cation exchange resin for the removal of Eu(III) from aqueous solution

Batch adsorption experiments were conducted for the adsorption of Eu(III) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(III) ion effectively from aqueous solution. The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.50 to 7.00 and the optimal adsorption condition was in HAc-NaAc medium with pH value of 6.50. The maximum uptake capacity of Eu(III) ions was 290.9 mg/g D113 at 298 K, at an initial pH value of 6.50. The overall adsorption process was best described by Lagergren-first-order kinetics. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The thermodynamic parameters such as free energy (?G) which were all negative, indicated that the adsorption of Eu(III) ions onto D113 resin was spontaneous and the positive value of enthalpy (?H) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. Furthermore, Eu(III) could be eluted by using 3.0 mol/L HCl solution and the D113 resin could be regenerated and reused.     

Adsorption and desorption properties of D151 resin for Ce(Ⅲ)

The present research is aimed at the development of D151 resin as an adsorbent that it can be used in the adsorption of Ce(Ⅲ) ions.The adsorption and desorption behaviors of Ce(Ⅲ) on D151 resin have been investigated by chemistry analysis.The influence of operational conditions such as contact time,initial concentration of Ce(Ⅲ),initial pH of solution and temperature on the adsorption of Ce(Ⅲ) had also been examined.The results show that the optimal adsorption condition of D151 for Ce(Ⅲ) was achieved at pH=6.50 in HAc-NaAc medium.The maximum uptake capacity of Ce(Ⅲ) was 392 mg/g resin at 298 K.The adsorption of Ce(Ⅲ) followed both the Langmuir isotherm and Freundlich isotherm,and the correlation coefficients had been evaluated.Even kinetics on the adsorption of Ce(Ⅲ) had been studied.The adsorption rate constant k298 K valued was 1.3×10-5 s-1.The calculation data of thermodynamic parameters which ΔS0 value of 91.34 and ΔH0 value of 7.07 kJ/mol indicate the endothermic nature of the adsorption process.While,a decrease of Gibb’s free energy(ΔG0) with increasing temperature indicated the spontaneous nature of the adsorption process.Finally,Ce(Ⅲ) could be eluted by using 0.5 mol/L HCl solution and the elution percentage was as high as 100%.Adsorption mechanism was also proposed for the adsorption of Ce(Ⅲ) ions onto D151 resin using infrared spectroscopy technique.     

D113离子交换树脂对Mn(Ⅱ)的吸附性能

在常温条件下研究D113树脂吸附Mn(Ⅱ)的过程。结果表明,当溶液pH为6.5～7.0、吸附时间120min时,废水中Mn(Ⅱ)离子去除率可以达到99%,吸附容量为136.98mg/g。盐酸浓度为3～4mol/L时,一次解吸率均达100%。该树脂对Mn(Ⅱ)的吸附曲线符合Langmuir和Freundlich吸附等温线,吸附交换过程符合HO准二级动力学方程式。内扩散系数随溶液pH、溶液中Mn(Ⅱ)浓度的增大而增大。     

离子交换树脂分离富集-分光光度法测定铜金精矿及尾矿中银

研究了732型阳离子交换树脂柱分离富集银的条件,建立了光度法测定铜精矿、金精矿及其尾矿中银的方法。实验表明,在pH 2~4的条件下,样品溶液中的银与硫脲络合以［Ag(SCN₂H₄ )₃］⁺形式被树脂吸附后,采用10 mL 0.5 mol/L的硫代硫酸钠溶液可定量洗脱,从而消除了绝大部分共存离子的干扰;树脂柱分离-富集后,硫代米蚩酮光度法测定银的检出限为5.0 μg/L。将本方法用于实际样品分析,测得结果与火焰原子吸收光谱法测定值一致,相对标准偏差(RSD,n=5)小于或等于14%,加标回收率为96%～102%。     

D296树脂从含钼酸性溶液中吸附钼的试验研究

针对含钼高温合金废料酸浸液中钼含量低的特点,采用离子交换法从含钼酸性溶液中提取钼,选用D296树脂吸附钼,通过动态试验考察了料液pH、流速和料液与树脂体积比对Mo吸附率的影响,并测定了Mo吸附曲线。结果表明,当反应温度为25℃,料液pH为2,吸附流速为4.5倍树脂床体积/h时,Mo吸附率达到94.74%;D296树脂对Mo的饱和吸附容量为50 mgMo/g。     

金属基树脂对含盐氨氮废水的吸附研究

盐分的存在使得氨氮废水的处理难度大大增加。在含盐条件下,利用负载过渡金属(Co2+、Ni2+、Cu2+、Zn2+)的D001树脂和D751树脂对氨氮废水进行了吸附实验。与负载前树脂相比,金属基D001(D751)树脂比表面积增大,且吸附氨氮后树脂形貌更为有序; 5次循环吸附氨氮后各金属离子依然牢固地固定在树脂上,说明金属基D001(D751)树脂稳定性较好。吸附动力学研究发现,金属基D001(D751)树脂对氨氮的吸附过程符合准二级动力学,且在吸附氨氮过程中吸附剂与吸附质之间存在由电子转移或共享产生的化学作用力。对金属基树脂对含盐氨氮废水吸附机理进行了剖析,结果表明金属基树脂与溶液中的氨氮存在配位吸附作用,通过配位共价键键合形成配体络合物。      

腐殖质对重金属离子的吸附作用

采用腐殖质对重金属离子进行了吸附试验。其结果表明 ,腐殖质对重金属离子具有强烈的吸附作用。腐殖质对Cu2 + 、Zn2 + 、Cd2 + 的吸附边界pH值分别为 4 2 ,5 8,7 2 ,吸附率可达 95 %以上 ;对Pb2 + 的吸附作用更加强烈 ,在pH值为 3 5时吸附率就达到 95 %以上 ,并且随着pH值的升高吸附率仍在 95 %以上。腐殖质对 4种重金属离子的吸附能力由强到弱的顺序是Pb2 + >Cu2 + >Zn2 + >Cd2 + 。腐殖质可以用来处理含重金属离子的污水 ,具有过滤快、沉降稳定、效果好的优点 ;也可作为土壤改良剂 ,有效地降低土壤中重金属的含量     

Adsorption and desorption properties of D151 resin for Ce(III)

The present research is aimed at the development of D151 resin as an adsorbent that it can be used in the adsorption of Ce(III) ions. The adsorption and desorption behaviors of Ce(III) on D151 resin have been investigated by chemistry analysis. The influence of operational conditions such as contact time, initial concentration of Ce(III), initial pH of solution and temperature on the adsorption of Ce(III) had also been examined. The results show that the optimal adsorption condition of D151 for Ce(III) was achieved at pH=6.50 in HAc-NaAc medium. The maximum uptake capacity of Ce(III) was 392 mg/g resin at 298 K. The adsorption of Ce(III) followed both the Langmuir isotherm and Freundlich isotherm, and the correlation coefficients had been evaluated. Even kinetics on the adsorption of Ce(III) had been studied. The adsorption rate constant k_{298 K} valued was 1.3×10^?5 s^?1. The calculation data of thermodynamic parameters which ΔS⁰ value of 91.34 and ΔH⁰ value of 7.07 kJ/mol indicate the endothermic nature of the adsorption process. While, a decrease of Gibb's free energy (ΔG⁰) with increasing temperature indicated the spontaneous nature of the adsorption process. Finally, Ce(III) could be eluted by using 0.5 mol/L HCl solution and the elution percentage was as high as 100%. Adsorption mechanism was also proposed for the adsorption of Ce(III) ions onto D151 resin using infrared spectroscopy technique.     

高含量银对活性炭从硫脲溶液中吸附金的影响

研究表明高含量银离子的存在将大大降低活性炭从硫脲体系中吸附金的吸附速率和吸附容量。这主要是由于大量银离子阻碍了金在溶液中的扩散以及金在活性炭上吸附过程的进行 ,同时少量银离子以大分子络合物的形式被吸附并占据了较大的活性炭表面所造成的。