Cd~（2＋）与Cu~（2＋）、Co~（2＋）、Ni~（2＋）的非有机溶剂萃取分离研究

本文研究了ＰＥＧ－Ｚｉｎｃｏｎ－（ＮＨ＿４）＿２ＳＯ＿４体系对Ｃｕ~（２＋）、Ｃｏ~（２＋）、Ｎｉ~（２＋）、Ｃｄ~（２＋）的非有机溶剂萃取行为，结果表明：在ｐＨ５．５～８．５（Ｋ＿２ＨＰＯ＿４－ＫＨ＿２ＰＯ＿４）的水溶液中，Ｃｕ~（２＋）、Ｃｏ~（２＋）、Ｎｉ~（２＋）可被ＰＥＧ相几乎完全萃取，而Ｃｄ~（２＋）基本上不被萃取，从而获得了Ｃｄ~（２＋）与Ｃｕ~（２＋）、Ｃｏ~（２＋）、Ｎｉ~（２＋）混合离子的定量分离。     

理化因子对嗜盐隐杆藻细胞生长及胞外多糖产量的影响

比较不同ＮａＣｌ、Ｃａ２＋、ＰＯ３－４等离子浓度对嗜盐隐杆藻（Ａｐｈａｎｏｔｈｅｃｅｈａｌｏｐｈｙｔｉｃａ）细胞生长及胞外多糖（Ｅｘｏｐｏｌｙｓａｃ－ｃｈａｒｉｄｅＥＰＳ）产量的影响。在各影响因子不同浓度的培养条件下,０．５ｍｏｌ／Ｌ的ＮａＣｌ、１．０ｇ／Ｌ的Ｃａ（ＮＯ３）２·４Ｈ２Ｏ、０．１ｇ／Ｌ的ＫＨ２ＰＯ４分别是其最佳生长浓度。ＥＰＳ的产量在０．５ｍｏｌ／ＬＮａＣｌ、,０．５ｇ／ＬＣａ（ＮＯ３）２·４Ｈ２Ｏ、０．５ｇ／Ｌ的ＫＨ２ＰＯ４培养条件下最高。在较低的Ｃａ２＋、Ｍｇ２＋、ＰＯ３－４浓度下可提高ＥＰＳ产率。     

磷酸氢二钾－磷酸二氢钾－聚乙二醇双水相体系热力学研究

本文建立了由磷酸氢二钾、磷酸二氢钾、聚乙二醇及水所组成的双水相体系（不含生物物质）的平衡浓度分析测定方法。实验共测定了ｐＨ＝９．４３及聚乙二醇数均分子量分别为１０００，２０００，４０００和６０００四种共４１组在２５℃下的液－液平衡数据；测定了聚乙二醇数均分子量为４０００和ｐＨ值分别为６、７、８时共３２组在２５℃下的液液平衡数据；实验还测定了Ｋ２ＨＰＯ４和ＫＨ２ＰＯ４在水中的缔合常数；用扩展的ＵＮＩＦＡＣ方程（短程项）和Ｆｏｗｌｅｒ－Ｇｕｇｇｅｎｈｅｉｍ方程（长程项）相结合进行了关联和预测，结果满意。同时还用Ｓｅｔｓｃｈｅｎｏｗ公式对双水相中上层贫盐水相进行关联，并发现此双水相体系遵循盐效应的一般规律。     

A3钢表面有机膦合钼聚多酸盐转化膜的研究

由Ｎａ２ＭｏＯ４·２Ｈ２Ｏ和Ｎａ２ＨＥＤＰ·５Ｈ２Ｏ合成了有机膦合钼聚多酸盐Ｎａ８［（ＨＥＤＰ）２Ｍｏ５Ｏ２１］·５Ｈ２Ｏ。用Ｎａ８［（ＨＥＤＰ）２Ｍｏ５Ｏ２１］·５Ｈ２Ｏ的溶液处理Ａ３钢，获得了具有一定耐蚀性的黄色转化膜，适宜的工艺条件为：浓度１６ｇ·Ｌ－１，ｐＨ３．５，温度５０℃，时间８０ｓ。本文还报告了膜层的ＸＰＳ和ＡＥＳ分析结果。     

静态混合器气液接触有效表面和传质系数的研究

以ＣｏＳＯ４作催化剂、ＫＨ２ＰＯ４－ＮａＯＨ缓冲溶液控制ｐＨ值，用Ｎａ２ＳＯ３水溶液－空气氧化法测定了ＳＫ１０和ＳＫ２５静态混合器的有效表面及ＳＫ２５静态混合器的液相传质系数，并得出有效表面和传质系数的关系式。     

聚乙二醇在无皂乳液共聚体系中的应用

在苯乙烯（Ｓｔ）和丙烯酸正丁酯（ＢＡ）的无皂乳液共聚体系中,加入聚乙二醇（ＰＥＧ）作相转移催化剂,考察了其浓度、分子量以及Ｋ２Ｓ２Ｏ８引发剂浓度对反应动力学的影响。讨论了相转移催化作用机理。     

无机盐对染料与非离子表面活性剂相互作用的影响

用光度法研究了对非离子表面活性剂ＴＸ－１００有盐溶、盐析作用的两种无机电解质（Ｎａ_２ ＳＯ_４和ＫＳＣＮ）对离子染料（漂蓝６Ｂ）与ＴＸ－１００相互作用的影响,得到了３种体系的相互作用常数 Ｋ及临界胶团浓度 ＣＭＣ。对于 ＥＣＡＢ＋ ＴＸ－ １００, ＥＣＡＢ＋ ＴＸ－ １００＋ Ｎａ_２ ＳＯ_４和 ＥＣＡＮ＋ ＴＸ－ １００＋ ＫＳＣＮ ３种体系,其 Ｋ值分别为 ２５５０, ７５３２和２４００ｄｍ_３· ｍｏｌ~（－１）; ＣＭＣ值分别为 ２． ５ × １０~（－４）,１．８７×１０~（－４）和１．８３×１０~（－４）ｍｏｌ·ｄｍ~（－３）。对所得结果作了合理解释。     

LARGE SCALE PURIFICATION OF PHOSPHOGLYCERATE KINASE（PGK） AND GLYCERALDEHYDE 3－PHOSPHATE DEHYDROGENASE（GAPDH） FROMYELLOW PEAS BY PEG／REPPAL PES AQUEOUS TWO PHASE SYSTEM AND ION EXCHANGE CHROMATOGRAPHY

ＬＡＲＧＥＳＣＡＬＥＰＵＲＩＦＩＣＡＴＩＯＮＯＦＰＨＯＳＰＨＯＧＬＹＣＥＲＡＴＥＫＩＮＡＳＥ（ＰＧＫ）ＡＮＤＧＬＹＣＥＲＡＬＤＥＨＹＤＥ３－ＰＨＯＳＰＨＡＴＥＤＥＨＹＤＲＯＧＥＮＡＳＥ（ＧＡＰＤＨ）ＦＲＯＭＹＥＬＬＯＷＰＥＡＳＢＹＰＥＧ／ＲＥＰＰＡＬ...     

固体超强酸ZrO_2/SO_4~=和Fe_2/O_3/SO_4~=催化苯乙烯烷基化甲苯反应初探

固体超强酸ＺｒＯ２／ＳＯ＝４和Ｆｅ２／Ｏ３／ＳＯ＝４催化苯乙烯烷基化甲苯反应初探ＣＡＴＡＬＹＩＣＡＬＫＹＬＡＴＩＯＮＲＥＡＣＴＩＯＮＯＦＴＯＬＵＥＮＥＡＮＤＳＴＹＲＥＮＥＢＹＵＳＩＮＧＳＯＬＩＤＳＵＰＥＲＡＣＩＤＳＺｒＯ２／ＳＯ４＝ＡＮＤＦｅ２／Ｏ／...     

pH值对Ti（O~nBu）_4－Ba（OAc）_2水解法合成BaTiO_3粉体

以乙酸和氢氧化钾为辅助原料，通过Ｔｉ（Ｏ￣ｎＢｕ）＿４－Ｂａ（ＯＡｃ）＿２水解法合成ＢａＴｉＯ＿３粉体。借助ＳＥＭ、ＴＥＭ、ＸＲＤ和ＥＰＭＡ等分析手段，研究了ｐＨ值对ＢａＴｉＯ＿３粉体性能的影响。论述了合成ＢａＴｉＯ＿３的反应机理，同时探讨了ｐＨ值对其反应机理的影响。     

Solvent Extraction of Au(I) from Auro‐Cyanide Solution with Cetyltrimethylammonium Bromide/Tri‐n‐Butyl Phosphate System using Column‐Shaped Extraction Equipment

Abstract

Solvent extraction of Au(I) from alkaline cyanide solution containing several milligram per liter of gold was investigated with column‐shaped extraction equipment using tri‐n‐butylphosphate (TBP) as extractant with addition of quaternary ammonium salt, cetyltrimethylammonium bromide (CTAB), directly into the aurous aqueous phase in advance. The influences of the volume of TBP and the NaCl concentration in the aurous aqueous phase on Au(I) extraction were investigated. The experimental results for treating 50 L of synthetic auro‐cyanide solution containing 10 mg/L Au(I) and for treating real auro‐cyanide leaching liquor by CTAB/TBP system were reported. The results obtained establish that the column‐shaped extraction equipment was suitable for extracting Au(I) from low content auro‐cyanide solution at high aqueous/organic phase ratio, and that more than 97% of gold(I) could be extracted while the Au(I) concentration in the raffinate was less than 0.3 mg/L. In addition, the stripping of Au(I) from the loaded organic phase and the recycle of the organic phase were also discussed.     

Solvent extraction of gold(I) from alkaline cyanide solution by dibutylcarbitol (DBC) with n‐octanol

BACKGROUND: Currently, cyanidisation is preferred for the extraction of gold because it has a number of advantages over other methods. Gold(I) can be extracted with various extractants, but there are no reports on the extraction of gold(I) from cyanide solution by dibutylcarbitol (DBC). In this work the extraction of gold(I) from alkaline cyanide solution using DBC with n‐octanol was studied. Several factors affecting the percentage extraction of gold(I), including DBC concentration, diluent concentration, equilibrium time, phase ratio, pH and gold concentration in aqueous phase, were investigated. RESULTS: The results showed that 96.2% of gold(I) could be extracted using an organic phase composed of 40% (v/v) DBC, 50% (v/v) n‐octanol and 10% (v/v) odourless kerosene. The extraction was quite fast and equilibrium could be established within 2 min. Stripping of the gold‐laden organic phase was carried out using sodium sulfite (Na₂SO₃) and sodium thiosulfate (Na₂S₂O₃) solutions, with Na₂S₂O₃ proving better than Na₂SO₃. The percentage stripping of gold(I) was 96.5% when the Na₂S₂O₃ concentration was 4% (w/w), and the stripping capacity of gold(I) exceeded 311.3 mg L^?1 when the phase ratio (A/O) was equal to 0.2. CONCLUSION: Gold(I) can be extracted from aqueous cyanide solution by DBC in the presence of n‐octanol and efficiently stripped by aqueous Na₂S₂O₃ solution. This method has the potential for practical application in the extraction and separation of gold. Copyright © 2008 Society of Chemical Industry     

The effects of pH on the partitioning of aromatic acids in a polyethylene glycol/dextran aqueous biphasic system

Distribution ratios of acidic, neutral, and basic compounds were determined in polyethylene glycol (PEG)-6000/Dextran-75000 aqueous biphasic systems (ABSs) at incremental pH values. The nature of the solute species present at each pH was identified using speciation diagrams, and it was determined that the distribution ratios were related to their charge, with maximum distribution to the upper PEG-rich phase when the neutral species were dominant. The results suggest that this ABS is tunable with simple modifications of pH leading to increasing selectivity for specific target solutes.     

用磷酸三丁酯萃取分离硫酸铵母液中的HCN

研究了磷酸三丁酯(TBP)-磺化煤油体系从重庆某企业甘氨酸生产副产物硫酸铵母液中萃取分离HCN的工艺,考察了萃取体系、TBP体积分数、母液初始pH值、相比(Vorg∶Vaq)对萃取HCN的影响以及氢氧化钠浓度、相比(Vaq∶Vorg)和平衡pH值对HCN反萃的影响。结果表明:选用TBP作为萃取剂能够对硫酸铵母液中的HCN进行快速有效的萃取;TBP体积分数、母液初始pH值及相比对HCN萃取率影响显著;以含体积分数35%TBP的有机相作萃取剂,在相比(Vorg∶Vaq)为2∶1的条件下,pH值为2.92的含氰1.71 g/L的硫酸铵母液经3级错流萃取,萃余液中含氰低于0.5 mg/L,氰的萃取率接近100%;在相比(Vaq∶Vorg)为1∶1条件下,以0.6 mol/L的氢氧化钠为反萃液,控制反萃液平衡pH值大于13.0,氰的单级反萃率大于96%;含氰0.78 g/L的有机相在相比为1∶1条件下,经过2级错流反萃,氰基本上被反萃完全,贫有机相不经过处理可循环使用。     

SELECTIVE AND QUANTITATIVE PARTITIONING OF PERTECHNETATE IN POLYETHYLENE-GLYCOL BASED AQUEOUS BIPHASIC SYSTEMS

ABSTRACT

The partitioning behavior of technetium has been investigated in polyethylene glycol (PEG)-based aqueous biphasic systems using K₃P0₄, K₂C0₃, Na₃(citrate), (NH₄) ₃(citrate), (NH₄) ₂S0₄, and NaOH as biphase-forming salts, and PEGs with average molecular weights of 1500, 2000, 3400, and 6000. Pertechnetate quantitatively partitions to the PEG-rich phase in these systems. The distribution ratios increase with increasing salt or PEG concentration used to form the aqueous biphasic systems, consistent with the increasing phase incompatibility. At a given concentration of salt and PEG, D_Tc values in the various systems increase in the order NaOH < (NH₄) ₂S0₄ < (NH₄)3(citrate) < K₂C0₃ < K₃P0₄ and PEG-1500 < PEG-2000 < PEG-3400 < PEG-6000. The distribution ratios are lower at very high or very low pH values than they are in the 3-9 pH range. Matrix ions may also influence the D_Tcvalues by affecting the aqueous biphasic system composition. Technetium can be stripped from the loaded PEG-rich phase by contact with a clean salt solution containing SnCl₂, which reduces TcO₄ to an oxy-chloro cationic species that partitions to the salt-rich phase.     

Three-liquid-phase extraction and separation of V(V) and Cr(VI) from acidic leach solutions of high-chromium vanadium–titanium magnetite

A new method by liquid–liquid–liquid three phase system, consisting of acidified primary amine N1923(abbreviated as A-N1923), poly(ethylene glycol)(PEG) and (NH_4)_2SO_4 aqueous solution, was suggested for the separation and simultaneous extraction of V(V) and Cr(VI) from the acidic leach solutions of highchromium vanadium–titanium magnetite. Experimental results indicated that V(V) and Cr(VI) could be selectively enriched into the A-N1923 organic top phase and PEG-rich middle phase, respectively, while Al(III)and other co-existing impurity ions, such as Si(IV), Fe(III), Ti(IV), Mg(II) and Ca(II) in acidic leach solutions,could be enriched in the(NH_4)_2SO_4 bottom aqueous phase. During the process for extraction and separation of V(V) and Cr(VI), almost all of impurity ions could be removed. The separation factors between V(V) and Cr(VI) could reach 630 and 908, respectively in the organic top phase and PEG middle phase, and yields of recovered V(V) and Cr(VI) in the top phase and middle phase respectively were all above 90%.Various effects including aqueous p H, A-N1923 concentration, PEG added amount and(NH_4)_2SO_4 concentration on three-phase partitioning of V(V) and Cr(VI) were discussed. It was found that the partition of Cr(VI) into the PEG-rich middle phase was driven by hydrophobic interaction, while extraction of V(V) by A-N1923 resulted of anion exchange between NO_3~- and H_2V_(10)O_(28)~(-4). Stripping of V(V) and Cr(VI) from the top organic phase and the middle PEG-rich phase were achieved by mixing respectively with NaNO_3 aqueous solutions and Na OH-((NH_4)_2SO_4 solutions. The present work highlights a new approach for the extraction and purification of V and Cr from the complex multi-metal co-existing acidic leach solutions of high-chromium vanadium–titanium magnetite.     

Process Design for Purification of Muscle Lactate Dehydrogenase by Affinity Partitioning Using Free Reactive Dyes

ABSTRACT

It was shown that by using free reactive dyes as affinity ligands, lactate dehydrogen-ase (LDH) can be purified with affinity partitioning directly from rabbit muscle homogenization. The free reactive dyes not bound to polyethylene glycol (PEG) showed a strong tendency toward the top PEG-rich phase in aqueous two-phase systems, and thus enhanced the affinity partitioning effect. Wide-ranged reactive dyes were screened in terms of their partitioning abilities for LDH. The effects of various parameters on affinity partitioning behavior of LDH, such as phase composition, impurities in raw material, concentration of dyes, pH of the systems, and addition of salts, were studied. The optimized affinity extraction process has been carried out for the large-scale purification of LDH from rabbit muscle homogenization. The enzyme was recovered with a yield of 81*middot;3% and a purification factor of 7. Both PEG and dyes were recovered and reused directly without lowering the quality of the product.     

Solvent Extraction of Gold(I) from Alkaline Cyanide Solution with Furfuryl Thioalcohol

A facile approach was designed to extract gold(I) from alkaline cyanide solution via a hydrometallurgy method. The performances of gold(I) extraction with furfuryl thioalcohol were investigated. The results revealed that gold(I) extraction increased with increasing extractant concentration and phase ratio but decreased with increase of pH value and god(I) concentration. The transfer speed of gold(I) between two phases was rather fast, and the extraction equilibrium could be established within 2 min. The extraction of gold(I) reached 92.7% with 15% (V/V) extractant. Gold(I) loaded in organic phase was stripped by NaOH solution, and stripping of gold(I) reached 90.2% with 0.08 mol · L^?1.     

Stripping of Au(I) from a Loaded Cetyltrimethylammonium Bromide/Tributyl Phosphate Organic Solution: Conversion and Reduction

The recovery of Au(I) from cyanide leaching solutions by solvent extraction techniques has attracted wide interest in the past decades. However, no substantial progress in industries has been reported yet, because of the difficulties concerning gold stripping from loaded organic phases, such as the quaternary amines extraction systems. In this work, a new technique for the recovery of Au(CN)₂ ^? from the loaded cetyltrimethylammonium bromide / tributyl phosphate organic solution by a two‐step stripping procedure is suggested first by Au(CN)₂ ^? conversion by HCl into corresponding chloride complex ions, and then by chemical reduction of auro‐chloride complex ions in TBP organic phases to give metal gold powder. The influences of HCl concentrations, reaction time, and various reducing agents used on the percent gold conversion and reduction were investigated. About 33% of Au(CN)₂ ^? in the initial TBP organic phase could be precipitated as metal gold powder in the conversion step, while 67% was converted into AuCl₂ ^? or AuCl₄ ^? and held in the organic phase. Subsequently, the loaded organic phase after conversion was contacted with reducing agents such as sodium sulfite, ammonium oxalate, or hydrazine hydrate. Most (>98%) of the auro‐chloride complex ions could be effectively reduced as metal gold. As a result, the total gold recovery from the initial TBP organic phases after the two stripping procedures achieved more than 98%. The ¹⁹⁸Au radioactive tracer was employed to determine the concentration and distribution behavior of gold in both organic and aqueous solutions. In addition, the experiment on the reuse of the organic phase after gold stripping showed that there was no obvious loss in percent gold(I) recovery after one cycle of the extraction‐ stripping‐ regeneration process no matter what reducing agent was used.     

用198Au示踪法研究季铵盐体系萃取金

The solvent extraction of KAu(CN)2 from alkaline solution by quaternary ammonium salts (trialkylmethylammonium chloride or cetyltrimethylammonium bromide) waw investigated by means of ^198Au radioactive tracer method. Various parameters,such as the gold (I) concentration in aqueous phase,the modiffer,emulsifiation at the interface of two phases, and phase ratio used in the extraction of gold (I) were studied. The results demonstrate that almost all gold (I) in the aqueous phase was practically extracted into the organic phase. The water content in the organic phase decreased significantly with increase of gold (I) concentration using long chain alcohol as modifier,in contrast with the system with tributyl phosphate (TBP) as modifier. Emulsification at the interface of two phases decreases with an increase of modifier concentration in the organic phase or with the addition of a small amount of lysozyme into the aqueous phase. The method with ^198Au tracer can be directly used to determine the Au(I) concentration both in aqueous and organic phases, which is especially suitable for the low concentration of Au(I).