水性氯化物介质中对甲基苯烷基硫醚萃取钯的研究

p-Methylphenylalkylsulfide of various alkyl chain length as extractant were synthesized and the extraction of palladium was examined in terms of equilibrium and kinetics. Distribution ratio of Pd was independent of alkyl chain length. For aqueous chloride media, there was a significant difference in distribution ratios for the solution of NaC1 and HC1. The results of loading test and the slope analysis suggest that the extractant and Pd (Ⅱ) form 2:1 complex. Furthermore, the extraction rate based on the volume of aqueous phase was obtained in a stirred vessel, and the rate equation was presented. Unfortunately, it was difficult to construct surfactant liquid membrane system by use of the present extractant.     

氯化物介质中甲基橙的电降解行为研究

采用电催化氧化技术处理一种偶氮染料甲基橙的模拟废水,研究了不同类型支持电解质对甲基橙降解效果的影响,分析了电化学体系中氯离子的作用机理.通过对电流密度、电解质浓度等影响因素,以及中间产物图谱的分析,初步得出了氯化物介质中甲基橙的电降解历程.     

钯的二苄基硫醚固相萃取分离研究

基于二苄基硫醚与钯的配合反应,建立了一种高选择性固相萃取吸附钯的方法。在0.1 mol/L的盐酸介质中,钯可以被二苄基硫醚树脂吸附富集并形成1∶2稳定配合物,该配合物可用20 g/L酸性硫脲洗脱,洗脱液经处理后用分光光度法测定,柱可以再生和重复使用,且萃取剂流失少。二苄基硫醚对钯的吸附是配位萃取机理;方法用于吸附分离钯选择性高,钯的回收率达95%以上。     

HS-LIX65N从氯化物介质中萃铜的萃取动力学研究

采用HS-LIX65N为萃取剂(稀释剂为Escaid 100)进行了从氯化物(CuCl_2-NaCl-HCl)介质中萃取铜的动力学研究.实验在一恒界面池(Lewis cell)中进行,本文着重研究了不同的两相组成对铜的萃取传质速率的影响.在判定HS-LIX65N从氯化物介质中萃取铜的控制机制为带有吸附和解吸过程的界面化学反应的基础上,确定了铜的1-2络合物(即CuR_2)的生成为反应控制步骤;而且实验结果表明,在一定的实验条件下,CuCl+是主要的被萃取组分.在理论分析的基础上,建立了如下萃取动力学模型:N_(cu)=[RH]i/a_(H~+)[1.791×10~(-5)(a_(cu~(2+))+1.882×10~(-4)(a_(CuCl~+)]用此模型计算所得结果与实验结果的平均偏差为5.29%.     

三氟甲基苯硫醚的制备和应用

本文介绍了三氟甲基苯硫醚的制备方法和它的具体应用。     

蛇纹石中钯的萃取

为了探讨蛇纹石中钯的有效萃取方法,进行蛇纹石浸出液萃取条件选择及萃取物还原实验。在盐酸介质中,以二(2 乙基己基)二硫代磷酸(D2EHDTPA)为萃取剂,浸出液pH为1,萃取时间为30min,钯的提取率达98%。     

高相对分子质量间苯撑硫醚-对苯撑硫醚的合成

以硫氢化钠、氢氧化钠、对二氯苯、间二氯苯为主要原料,有机锂盐和无水乙酸钠为催化剂和助剂,N-甲基吡咯烷酮(NMP)为极性有机溶剂,在2 L高压反应釜内于220~250℃反应6 h合成间苯撑硫醚-对苯撑硫醚树脂(m-p-PPS)。为提高树脂的相对分子质量,在反应后期加入活性单体4,4'-二氯二苯甲酮(DCBP)共聚得到间苯摩尔分数为10%~40%的系列m-p-PPS共聚物。对合成的共聚物进行特性黏度测试、红外光谱分析、X-射线衍射分析、热分析及溶解性能测试等分析表征工作,结果表明:共聚物为部分结晶性线型高分子,随着间苯含量的增加,共聚物相对分子质量降低,结晶能力减弱,热稳定性降低,而溶解性能增强;添加少量DCBP对树脂结构影响不大,但能有效提高树脂的相对分子质量。     

聚对苯硫醚,聚间苯硫醚及共聚物的合成与表征

用硫磺，对二氯苯和间二氯苯为原料，在极性有机溶剂六甲基磷酰三胺中合成了聚对苯硫醚，聚间苯硫醚及其共聚物。用裂解气相色谱，红外光谱，Ｘ－射线衍射及热分析对所得聚合物的结构和热性能进行了初步研究。结果表明：ｐ－ＰＰＳ和ｍ－ＰＰＳ都是结晶性聚合物，间位结构引入到ｐ－ＰＰＳ的结构中明显地破坏了ｐ－ＰＰＳ的高度结晶性，降低了耐热性，但最大失重速率处温度却无多大变化。这一共聚改性途径可望用于改进ｐ－ＰＰＳ的刚     

Palladium Extraction by a Malonamide Derivative (DMDOHEMA) from Nitrate Media: Extraction Behavior and Third Phase Characterization

Liquid-liquid extraction of palladium(II) from nitric media was carried out using, N,N’–dimethyl,N,N’-dioctylhexylethoxymalonamide (DMDOHEMA) in n-heptane. To this purpose, various experimental parameters such as reaction time, extractant concentration, pH, and nitrate concentration were investigated in detail. Efficient extraction of palladium can then be achieved, with good distribution coefficients (D up to 10) and performing kinetics (equilibration time ca. 30 min). In some cases, a solid phase appears at the interface between aqueous and organic layers. It was characterized as a palladium(II) complex with DMDOHEMA with appropriate techniques, and the conditions of its formation are discussed.     

Extraction of Chloride Ions from Zinc-Bearing Waste Lixivium by Trioctyl Amine (TOA)

This paper presents research on separating Cl^? from zinc-bearing waste lixivium by using trioctylamine as an extractant, 2-octanol as a solvent, and sulfonated kerosene as a diluent. The effects of trioctylamine concentration, organic/aqueous phase ratio, extracting stages, and waste lixivium pH were investigated, and the process of stripping was also discussed. The optimal conditions were achieved. The extraction efficiency, separation factor, and stripping efficiency were calculated with optimal values of 99.47%, 595, and 99.99%, respectively. Besides, the extractant regenerated after stripping was observed without the emulsifying phenomenon. The mechanism of extraction and stripping was also discussed.     

蛇纹石中微量钯的提炼

介绍了蛇纹石的熔融、酸解等处理过程 ,重点叙述了从蛇纹石中提取微量贵金属钯的工艺流程和操作方法。钯的提取率为 90 .5 %。     

Solid-Phase Extraction of Pt(IV) with Dialkyl-(hexane-1,6-diyl) Phosphate Modified Merrifield Resins from Aqueous Chloride Media in Column Operations

A series of three dialkyl phosphate resins with a Merrifield resin support was used to extract platinum from acidic media. In column operations total capacities of 85-130 mg/g were gained. The presence of palladium and rhodium results in the order: Pt(IV) > Pd(II) >> Rh(III). From a leach liquor gained from spent automotive catalysts metals forming anionic chloro complexes are co-extracted only to a small extent. However, in order to separate and enrich platinum a selective back-extraction can be done with a sodium thiocyanate solution. A second elution step with acidic thiourea leads to a mixed solution of palladium and rhodium.     

PEG-(NH_4)_2SO_4双水相萃取法提取壳聚糖酶的研究

采用PEG-(NH4)2SO4双水相体系直接从Bacillussp.LS发酵液上清液中分离壳聚糖酶。研究了体系中PEG分子量、PEG质量分数、(NH4)2SO4质量分数、NaCl质量分数和pH值对壳聚糖酶分配系数及萃取率的影响。结果表明,室温下双水相萃取最佳条件为:PEG600 20%、(NH4)2SO420%、NaCl 0.1%、pH值6.0,在此条件下壳聚糖酶分配系数达5.91,萃取率达88.7%。     

The Solvent Extraction Performance of N,N’-Dimethyl-N,N’-Dibutylmalonamide Towards Platinum and Palladium in Chloride Media

The solvent extraction performance of N,N’-dimethyl-N,N’-dibutylmalonamide (DMDBMA) in 1,2-dichloroethane (1,2-DCE) towards platinum(IV) and palladium(II) in hydrochloric acid media was systematically evaluated. Pt(IV) extraction (%E) increases with the HCl concentration in the aqueous phases, being always higher than 72%, whereas Pd(II) extraction decreases from 65% at 1 M HCl to 22% at 8 M HCl. Several stripping agents for the two metals were tested: Pt(IV) is successfully recovered by a 1 M sodium thiosulfate solution, whereas the best result for Pd(II) was achieved with 0.1 M thiourea in 1 M HCl. The loading capacity of DMDBMA for Pt(IV) is high, and data obtained from successive extraction-stripping cycles suggest a good DMDBMA stability pattern. Attempts to replace 1,2-DCE by more environmentally-friendly diluents showed, in general, worse %E for Pt(IV). The dependence of Pt(IV) distribution coefficients on DMDBMA and chloride ion concentrations, as well as on acidity, are the basis of a proposal for the composition of Pt(IV) extracted species.     

双水相分离纯化荷叶中黄酮类化合物

采用PEG/硫酸铵双水相体系分离纯化荷叶黄酮。实验结果表明：在PEG 4000的质量分率为25%,（NH4）2SO4的质量分率为10%,加入粗提液3 mL,在常温下,荷叶黄酮的萃取率可达97%以上。