氨基酸在铜离子浊点萃取中的应用

采用紫外光谱分析技术,考察了以不同氨基酸为络合剂时铜离子的浊点萃取效率,确定最佳的络合剂为甘氨酸。并将浊点萃取和紫外分光光度法联合应用于环境水样中痕量铜离子的分离和测定,效果较好。     

浊点萃取-光度法测定卷烟纸中磷酸盐

建立了分光光度法测定卷烟纸中痕量磷酸盐的浊点萃取分离富集体系。磷酸根离子在酸性介质中与钼酸盐反应生成磷钼酸盐,可溶性磷钼酸盐与阳离子表面活性剂溴化十六烷基三甲基铵(CTAB)形成疏水性的离子对缔合物,进行浊点萃取,采用光度法测定。研究了溶液的酸度、试剂用量、平衡时间、平衡温度、干扰离子对浊点萃取效果的影响,并得到最佳测定条件:5%的Triton X-114用量0.8m L、平衡温度60℃、平衡时间15min,将表面活性剂富集相用乙醇分散稀释,应用紫外-可见分光光度计在700 nm波长处测定。测定的线性范围为5.0~500 ng/m L,方法的检出限为0.5ng/m L,相对标准偏差(RSD)为1.1%~3.5%。     

浊点萃取-火焰原子吸收光谱法测定乙醛触媒微量钯含量

建立了以1-（2-吡啶偶氮）-2-萘（PAN）为络合剂,以非离子表面活性剂TritonX-100为萃取剂的浊点萃取分离富集-火焰原子吸收光谱法测定痕量钯的新方法。研究了溶液的酸度、络合剂和表面活性剂浓度、平衡温度和时间、离子强度等条件对浊点萃取效果的影响。该方法对钯的检出限为35．3ng／mL,相对标准偏差（RSD）为3．1％（n=8）,回收率97．6％0～106．7％。可用于乙醛催化剂中微量Pd（Ⅱ）的测定。     

离子液体萃取-火焰原子吸收光谱法测定痕量铜

以N-正丁烷基苯并噻唑六氟磷酸盐温敏性离子液体为萃取剂,乙腈为分散剂,萃取富集痕量铜离子,用火焰原子吸收法测定,建立了一种快速、简便分析铜离子的新方法。考察了离子液体的浓度、冰浴时间、溶液p H、萃取温度、萃取时间等对萃取率的影响。结果表明,方法检出限为0.18μg/L,相对标准偏差(RSD)为1.09%;对矿泉水和绿茶中铜离子进行分别检测,加标回收率为98.5%~105.1%。     

离子液体[BPy]BF_4双水相萃取芦丁的研究

建立了由亲水性离子液体四氟硼酸N-丁基吡啶[BPy]BF4和(NH4)2SO4形成的双水相体系萃取分离芦丁的新方法。研究了(NH4)2SO4浓度、芦丁溶液浓度、离子液体用量和溶液酸度对双水相形成和萃取率的影响。结果表明,当双水相体系组成为:(NH4)2SO41.5 g,2.0 mL离子液体,1.0~1.2 mL芦丁溶液,溶液酸度在pH4~6范围内,该离子液体双水相体系对芦丁有较高的萃取率(E%>90)。     

盐酸改性蒙脱土对废水中铜离子的吸附研究

以蒙脱土为原料,经1mol/L盐酸改性处理后将其用于废水中铜离子的吸附,研究了吸附时间、pH值、土用量和铜离子初始浓度对铜离子吸附率的影响。结果表明:当铜离子浓度为10mg/L,溶液体积为50mL,pH值为6,蒙脱土用量为0.4g,吸附时间为1 h时铜离子的吸附率可达到91.48%。     

浊点萃取-192紫外可见分光光度法测定痕量铝

研究了浊点萃取(CPE)-紫外可见分光光度法测定痕量铝离子的新方法,利用非离子表面活性剂Triton X-114对铝试剂与铝离子形成的络合物进行浊点萃取。探讨了影响浊点萃取及测定灵敏度的因素。在最佳条件下,铝离子的富集倍率为13.5倍,检出限为0.33μg/L,RSD为0.2%(n=6),铝离子含量在10~150μg/L范围内服从比尔定律。本法对实际样品中的铝进行富集和测定,结果令人满意。     

浊点萃取-原子吸收法测定水中微量的铅

基于5-Br-PADAP与铅形成稳定的螯合物能被TritonX-114浊点萃取的事实,建立了浊点萃取-原子吸收法测定水中微量的铅的新方法。铅的浓度在0~30μg/mL内呈线性,检测限为1.7 ng/mL;相对标准偏差（n=11）为2.7%,加标回收率为97.5%~102.5%。     

非离子表面活性剂为溶媒的浊点萃取技术

非离子表面活性剂溶液在温度高于其浊点或有一定添加物存在时,会自动形成表面活性剂浓度很小的稀相和表面活性剂浓度很高的凝聚层相,存在于这一系统的溶质将不均匀地分配于二相。文章结合研究成果,综述了这一新型浊点萃取技术的基本理论和应用,同时也介绍了浊点萃取在微生物转化中的新应用。     

浊点萃取-高效液相色谱法测定某些中草药中铜的研究

基于浊点现象,建立了以双硫腙为配位剂、TritonX-114为表面活性剂的浊点萃取-高效液相色谱法测定中草药中痕量铜的新方法。研究了溶液pH值、配位剂的浓度、表面活性剂的浓度、平衡温度和平衡时间、流动相类型等实验条件对浊点萃取及铜测定的影响。在最佳试验条件下,该方法的线性范围为0．1—120μg·L^-1,相关系数达0．997-0．999,铜的检出限达到0．1μg·L^-1。相对于传统的液相色谱分析法灵敏度提高了18倍。该方法成功用于中草药样品中铜的测定并获得了满意的结果。     

Micelle-Mediated Extraction and Cloud Point Preconcentration of Chlorophylls from Spinach

A micelle-mediated extraction and cloud point preconcentration of chlorophylls method was developed. Non-ionic surfactant (Genapol X-080) was employed as an alternative and effective extraction solvent. The optimal extraction parameters based on the micelle extraction technique were determined. Under optimal conditions, i.e., 5% Genapol X-080 (v/v), pH 9.0, liquid/solid ratio of 10:1 (mL g^?1), ultrasonic-assisted extraction for 30 min, extraction amount reached the highest value. For the preconcentration of chlorophylls by cloud point extraction (CPE), the solution was incubated at 50° for 30 min, and 0.1 g mL^?1 sodium chloride was added to the solution to facilitate the phase separation. The microstructure of coacervate phase after CPE was explored with transmitting electron microscopy. The preconcentration factor for chlorophylls was about 12.5, the extraction recovery approached 99.2%, and the loading capacity was about 1 mg mL^?1. Thus coupling of ultrasonic-assisted micelle extraction and cloud point extraction could be employed as a new and effective technique for the rapid extraction and preconcentration of chlorophylls from plants such as spinach.     

交联壳聚糖对废水中Cu2+的吸附性能

以壳聚糖为原料制备交联壳聚糖吸附剂,并将其用于吸附废水中的Cu2+,考察了交联剂的用量、溶液中Cu2+初始浓度、pH、温度和时间等对交联壳聚糖吸附性能的影响。结果表明,壳聚糖与交联剂的用量比为m(壳聚糖)∶V(甲醛)∶V(戊二醛)=1.5g∶6mL∶4.5mL、溶液pH为6,溶液中Cu2+初始浓度为5mmol/L时吸附效果最佳,且吸附量随着温度升高而增加,吸附表现为吸热过程。     

Pd~(2+)-I~--TBAB三元缔合物萃取光度法测定钯含量

介绍了Ｐｄ２＋－Ｉ－－ＴＢＡＢ（四丁基溴化铵）三元缔合物萃取光度法测定钯的方法。该方法以Ｌ（＋）抗坏血酸作为掩蔽剂，干扰离子Ｃｕ２＋，Ｆｅ３＋的允许量均为２．５μｇ／ｍＬ，Ｐｄ２＋浓度为０～４μｇ／ｍＬ，完全符合比耳定律（萃取剂作参比），方法的相关摩尔吸光系数ε为２．０９×１０４Ｌ／（ｍｏｌ·ｃｍ），桑德尔灵敏度Ｓ为５．０７×１０－３μｇ／ｃｍ２。工作曲线的应用范围为１～４μｇ／ｍＬ。     

改性硅藻土处理含铜废水的试验研究

采用氢氧化钠改性的硅藻土作为吸附材料,研究了吸附剂用量、搅拌时间、pH值以及废水浓度等因素对吸附效果的影响。结果表明,在100 mL Cu2+的质量浓度为10.49 mg/L,改性硅藻土投加量为3.5 g,pH值为8.5,吸附时间为30 min的条件下,废水中Cu2+的去除率最高可达97.93%,出水Cu2+的质量浓度低于0.22 mg/L,达到了GB 8978—1996《污水综合排放标准》一级标准的要求。     

Removal of Copper(II) from a Concentrated Sulphate Medium by Cloud Point Extraction Using an N,N′-Bis(salicylaldehyde)Ethylenediimine Di-Schiff Base Chelating Ligand

Various chelating ligands have been investigated for the cloud point extraction of several metal ions. However, limited studies on the use of the Schiff base ligands have been reported. In this work, cloud point extraction behavior of copper(II) with N,N′‐bis(salicylaldehyde)Ethylenediimine Schiff base chelating ligand, (H₂SALEN), was investigated in aqueous concentrated sulphate medium. The extraction process used is based on the formation of hydrophobic H₂SALEN–copper(II) complexes that are solubilized in the micellar phase of a non‐ionic surfactant, i.e. ethoxylated (9.5EO) tert‐butylphenol. The copper(II) complexes are then extracted into the surfactant‐rich phase above cloud point temperature. Different parameters affecting the extraction process of Cu(II), such as equilibrium pH, extractant concentration, and non‐ionic surfactant concentration were explored. The extraction of Cu(II) was studied in the pH range of 2–11. The results obtained showed that it was profoundly influenced by the pH of the aqueous medium. The concentration factor, C_f, of about 17 with extraction efficiency of E % ≈100 was achieved. The stoichiometry of the extracted complex of copper(II) was ascertained by the Yoe–Jones method to give a composition of 1:1 (Cu:H₂L). The optimum conditions of the extraction‐removal have been established as the following: (1) 1.86 × 10^?3 mol/L ligand; (2) 3 wt% surfactant; (3) pH of 8 (4) 0.5 mol/L Na₂SO₄ and (5) temperature of 60 °C.     

铜离子在印迹壳聚糖/Al2O3上的吸附-脱附特性

采用表面接枝和表面印迹技术,以正硅酸乙酯改性后的Al2O3粉末为载体、壳聚糖为功能单体,制备了Cu2+印迹复合材料(IIP/Al2O3),用于选择性分离Cu2+. 研究了IIP/Al2O3对Cu2+的动态吸附,利用Thomas, Yoon-Nelson和Wolborska模型分析IIP/Al2O3吸附Cu2+过程,考察了动态条件下Cu2+的最佳洗脱条件. 结果表明,当Cu2+浓度100 mg/L、柱高37.25 mm、流速1.0 mL/min和pH=5时,IIP/Al2O3的穿透吸附容量和动态吸附容量分别为4.03和15.68 mg/g,Cu2+去除率为45.55%;Thomas和Yoon-Nelson模型能很好地拟合IIP/Al2O3对Cu2+的吸附;在柱高37.25 mm、洗脱液流速1.0 mL/min的条件下,15 mL 0.6 mol/L盐酸溶液对Cu2+的脱附率高达99.54%,脱附作用时间短,Cu2+易回收.     

Room temperature ionic liquid,cetyl pyridinium naphthenate,supported cloud point extractive separation and ultra trace determination of copper in blood and environmental samples

A new unconventional room temperature ionic liquid, cetyl pyridinium naphthenate (CPN) was synthesized and was ascertained by IR, NMR and CHN analysis. Cloud point extraction of Cu(II) was carried out by using CPN for a synergistic enhancement effect. Triton X 100 was used as surfactant in cloud point extraction and cloud point temperature was 750 C. Quantification was carried out by FAAS. The mean recovery, enrichment factor, tolerance limit, RSD, LOD and LOQ were found to be 99.8%, 40, 1000 ppm, 0.15%, 27 ppt and 93 ppt respectively. Method was validated by analyzing natural water and blood samples.