微乳液膜法萃取镍

采用油酸/丁醇/碳酸钠水溶液组成的微乳体系对水相中Ni2 进行萃取研究,考察了微乳体系组成,水相的pH值、膜水比、搅拌时间等实验参数对萃取率的影响,以及水相中NaCl盐度对微乳体系乳化的影响.实验结果表明:当油酸∶丁醇∶碳酸钠(1.0 mol/L)=5∶5∶4(体积比),油内比Roi为2.5,废水pH值在5.1~5.8间,膜水比Rew为1∶7,搅拌时间为6 min时,Ni2 萃取率达99.91%,由初始浓度0.5 g/L降至0.7 mg/L,水相中NaCl含量1.5 g/L,萃取过程中不存在溶胀现象.用盐酸调节pH值破乳,油相回用,实验结果证明5次回用后液膜萃取效果基本不变.     

乳化液膜去除焦化废水中苯酚的初步研究

采用乳化液膜法去除焦化废水中的苯酚,建立了以磷酸三丁酯(TBP)为载体、Span-80为表面活性剂、煤油作膜溶剂及NaOH溶液为内相的乳化液膜体系.首先采用红外光谱分析得出TBP与酚类物质属氢键缔合.其次通过液膜稳定性实验表明,当表面活性剂体积分数为5%、油内比为1∶1、制乳时间为30 min、制乳转速为2 000 r/min时,可以得到较为稳定的乳化液膜.最后根据分离实验结果得出,当表面活性剂体积分数为5%、NaOH溶液浓度为0.5 mol/L、载体体积分数为0.2%、乳水比为1/3时,苯酚的迁移率可达到95%以上.     

以HDEHP为载体的大块液膜迁移铕离子动力学研究

以二 (2 -乙基己基 )磷酸 (HDEHP)为载体 ,考察了搅拌速度、温度、石蜡及表面活性剂对大块液膜迁移铕离子的影响 ,获得了各种实验条件下的表观反应速率常数 ,萃取和反萃取的表观反应活化能分别为 1 0 .7kJ/mol和 2 9.2kJ/mol.结果表明 ,萃取过程扩散为控速步骤 ,反萃取过程化学反应亦为控速步骤 ,Eu(Ⅲ )离子的跨膜迁移过程可以以两个串联的准一级不可逆过程进行描述 .     

乳化液膜的制备及其在1-萘酚废水处理中的实验研究

在较低的转速下(720 r/min),将磁力搅拌和超声方法结合,制备煤油-Span80-NaOH乳化液膜,在较温和条件下制备了稳定性较高的乳化液膜.将制备的乳化液膜应用于1-萘酚废水溶液的处理.系统考察了液膜制备过程的影响因素,如NaOH浓度、超声时间、油内比等;废水处理的操作条件:外水相pH、接触时间和乳水体积比等因素对1-萘酚的去除效果.结果表明,NaOH浓度为2％、超声时间为5 min、油内比为1∶2、无需调节pH、接触时间为15min、乳水比为1∶5时,1-萘酚去除率可高达94％.     

微乳液-中空纤维膜萃取钕的工艺研究

提出了一种新的膜分离过程即非离子W/O型微乳液-中空纤维膜萃取,所用非离子型微乳液体系为(OP-7 OP-4)/苯甲醇/D2EHPA/煤油/盐酸.在不同微乳液流速、料液流速、微乳液内相盐酸浓度、料液浓度、以及不同中空纤维膜数等条件下进行了微乳液-中空纤维膜逆流萃取Nd3 的研究.结果表明,微乳液和料液流速越小,萃取率越高,内相富集倍数越大.微乳液内相盐酸浓度越大,萃取率越高,但富集倍数反而减小.料液初始浓度越小,萃取率和富集倍数越大.当微乳液流速为6 mL/min、料液与微乳液流速比为3∶1、微乳液内相盐酸浓度为4 mol/L、料液浓度为200 mg/L时,经过微乳液在三个中空纤维膜萃取器中的串联萃取,Nd3 的萃取率达96.3%,内相Nd3 浓度为4238 mg/L,是萃余料液浓度的572.7倍,内相富集倍数为21.2.膜萃取过程与膜溶剂萃取相比对Nd3 有更高的萃取效率.     

液膜接触法处理含铜废水的实验研究

探讨以P204为流动载体的液体表面活性剂膜从酸性水溶液中分离二价铜离子的过程，并对影响二价铜离子透过液膜的重要变量进行分析，这些变量主要是外部水相中的起始铜浓度、外相溶液中的起始pH值、液膜流动载体浓度、乳水比、内相峻浓度等．实验结果表明：较佳膜相组成的液膜能把废水溶液中铜离子浓度从100mg/L降到0．9mg/L;铜萃取率大于99％．     

废脱硝催化剂钒、钨的浸出-搅拌对浸出率的影响

实现废脱硝催化剂高效综合再利用具有重大的社会和经济效益。本文采用NaOH浸出废脱硝催化剂中钒钨离子并考察其浸出影响因素,对比研究了搅拌和不搅拌作用下废脱硝催化剂中的钨离子浸出动力学。结果表明,提高浸出温度和NaOH浓度均有利于钒、钨的浸出;在搅拌条件下(350 r/min),液固比3.5∶1,浸出温度160℃,NaOH浓度40%,浸出时间3.5 h,钒、钨浸出率均达到100%。动力学研究结果钨离子浸出过程属于固膜扩散控制,搅拌条件下钨浸出表观活化能为29.28 kJ/mol,而不搅拌时,其表观活化能仅为1.26 kJ/mol,搅拌强化可增加扩散速率,减小扩散阻力,强化钒钨的浸出。     

乳状液膜法提取赖氨酸

研究了用乳状液膜法提取赖氨酸的液膜配方及一些重要操作参数 ,初步得出了既能相对减少溶胀 ,又能保持较高分离效率的膜组成及最佳工艺条件 .赖氨酸提取的液膜组成为 :载体二 - (2 -乙基己基 )磷酸脂 7% (质量分数 ) ,表面活性剂 (Span - 80 ) 5 % (质量分数 ) ,膜溶剂 5 0 % (体积分数 )液体石蜡和 5 0 %煤油 .内相选用 0 .5mol/L的HCl溶液 ,处理比为 3.75 ,提取率可达 72 .6 %     

硫杂冠醚为载体的液膜中Ag（Ⅰ）的迁移研究

选择内耦合液膜技术,以CHCl3为膜溶剂,1,4,7,10,13,16-六硫杂-18冠-6(HT18C6)为流动载体,研究Ag(Ⅰ)在(HT18C6-CHCl3)液膜体系中的迁移过程.考察了载体的种类和浓度、料液相浓度、接受相的种类、浓度和pH值、搅拌速度以及温度等因素对Ag(Ⅰ)离子迁移过程的影响.结果表明,在最佳迁移条件下:载体浓度为5.0×10-4mol/L、料液相NaClO4浓度为5.0×10-3 mol/L、接受相Na2S2O3浓度为0.05 mol/L、搅拌速度为120 r/min、工作温度控制在293～313 K范围内,Ag(Ⅰ)的迁移率可达到99%以上.同时Hg(Ⅱ),M(Ⅱ),Ca(Ⅱ),Ni(Ⅱ),K(Ⅰ),Na(Ⅰ),Cr(Ⅲ),Zn(Ⅱ),Cu(Ⅱ),Pb(Ⅱ)和Cd(Ⅱ)等共存金属离子对Ag(Ⅰ)的迁移无影响.对废定影液样品中Ag(Ⅰ)进行迁移富集,银的回收率在99.3%～99.8%.     

密差分相式液膜法提取L-苯丙氨酸

采用密差分相液膜分离技术，以P204为载体，H2SO4为反萃剂，以初始浓度15．28g/L的L－苯丙氨酸水溶液提取5次后，浓度降至1．92g/L，反萃相中L－苯丙氨酸浓度达54．35g/L，膜溶胀和破裂均较小，过程不需要制乳和破乳；对反萃剂也进行了后处理。     

Temperature Dependence and P/Zn Ratio in Phosphoric Acid Treatment of Zinc Oxide

Zinc oxide,which has photocatalytic activity,is used as white pigment for cosmetics.A certain degree of sebum on the skin is decomposed by ultraviolet radiation in sunlight.In this work,zinc oxide was shaken with phosphoric acid to synthesize a white pigment for cosmetics.Zinc oxide was set with 0.1 mol/L of phosphoric acid at P/Zn=1/1 and 1/2,and then shaking in hot water for 1 h.The chemical composition,powder properties,photocatalytic activity,color phase,and smoothness of the obtained powder were studied.The P/Zn ratio in preparation had an effect on the reaction between phosphoric acid and zinc oxide.The photocatalytic activity of zinc oxide was inhibited by phosphoric acid treatment.The obtained samples had enough high reflectance at the visible light region.     

Selective extraction of zinc(II) over iron(II) from spent hydrochloric acid pickling effluents by liquid-liquid extraction

The selective removal of zinc(II) over iron(II) by liquid–liquid extraction from spent hydrochloric acid pickling effluents produced by the zinc hot-dip galvanizing industry was studied at room temperature. Two distinct effluents were investigated: effluent 1 containing 70.2 g/L of Zn, 92.2 g/L of Fe and pH 0.6, and effluent 2 containing 33.9 g/L of Zn, 203.9 g/L of Fe and 2 M HCl. The following extractants were compared: TBP (tri-n-butyl phosphate), Cyanex 272 [bis(2,4,4-trimethylpentyl)phosphinic acid], Cyanex 301 [bis(2,4,4-trimethylpentyl) dithiophosphinic acid] and Cyanex 302 [bis(2,4,4-trimethylpentyl) monothiophosphinic acid]. The best separation results were obtained for extractants TBP and Cyanex 301. Around 92.5% of zinc and 11.2% of iron were extracted from effluent 1 in one single contact using 100% (v/v) of TBP. With Cyanex 301, around 80–95% of zinc and less than 10% of iron were extracted from effluent 2 at pH 0.3–1.0. For Cyanex 272, the highest extraction yield for zinc (70% of zinc with 20% of iron extraction) was found at pH 2.4. Cyanex 302 presented low metal extraction levels (below 10%) and slow phase disengagement characteristics. Reactions for the extraction of zinc with TBP and Cyanex 301 from hydrochloric acid solution were proposed.     

A study on electric conductivity of phosphoric acid supported on nano-pore rice husk silica in H2/Pt/H3PO4 / RHS/Pt/O2 fuel cells

PEMFC (Polymer Electrolyte Membrane Fuel Cell) is widely considered as an energy conversion system from the chemical energy of hydrogen to electric energy. But, hydrogen fuel obtained from hydrocarbons has trace amount of carbon monoxide which is a potential poison for platinum electrode at the cell operating temperature approximately 100 degrees C and it becomes a huddle for the general usage of PEMFC. On the other hand PAFC (Phosphoric Acid Fuel Cell) operates at a higher temperature and the platinum electrode oxidizes carbon monoxide poison while there is a leakage problem of the liquid phase. To combine the advantages of two fuel cells, the electrolyte systems of phosphoric acid supported silica on ceramics are recently being tested. In this study, we investigated the nm pore rice husk silica as a support for phosphoric acid and tested the electric conductivity of the silica plate and the characteristics of a prototype fuel cell H2/Pt/H3PO4 / RHS/Pt/O2 at 100-200 degrees C. The conductivity of H3PO4/RHS was 8 mS cm(-1) above 175 degrees C under 200 torr H2O. In the fuel cell, the apparent conductance of the electrolyte from I-V characteristics was 2.45 mS/cm at 160 degrees C under 1 atm H2 and air at present.     

湿法磷酸工艺中镧系元素的富集与提取技术研究进展

在湿法磷酸生产过程中产生的粗磷酸母液和磷石膏中均含有微量的镧系元素。以这种潜在的稀土资源为研究对象,介绍了国外及云南省磷矿中稀土的含量及分布情况,探讨了湿法磷酸过程中镧系元素的转移机理,论述了从粗磷酸母液和磷石膏中回收提取镧系元素的方法、工艺以及高纯单一镧系元素的分离纯化技术,提出了云南省磷石膏中微量镧系元素提取技术是磷石膏综合利用的一个重要研究方向,对开发磷石膏的高附加值具有重要意义。     

Application of novel extractants for actinide(III)/ lanthanide(III) separation in hollow-fibre modules

Separation tests using hollow-fibre modules were performed for the difficult selective extraction of trivalent actinides over fission lanthanides from acidic media. This article shows that with 2,6-di(5,6-dipropyl-1,2,4-triazin-3-yl)pyridine as the extractant, up to 94% americium could be extracted from 1.0 kmol/m³ HNO₃, with minimal lanthanide co-extraction. Using a synergistic mixture of bis(chlorophenyl)dithiophosphinic acid and tri-n-octyl phosphine oxide, tests were performed on extraction, lanthanide scrubbing and stripping. In the extraction test, up to 99.99% americium could be extracted from 0.5 kmol/m³ HNO₃, with approximately one third of the lanthanides being co-extracted. Mass transfer calculations using a consistent set of input data showed good agreement with the experiments.     

正交实验法研究液膜提取黄连素的最佳条件

对影响黄连素提取量的几个因素进行正交实验，结果表明在油内比等于：1.5，膜内HCl浓度为0.8mol\L，载体油酸用量为0.075mol\L，乳化剂Span-80用量为2.5%（质量分数）时，黄连素提取量可达总含量的75%以上。     

Adsorption of Zn(II) in aqueous solution by activated carbons prepared from evergreen oak (Quercus rotundifolia L.)

In the present work activated carbons have been prepared from evergreen oak wood. Different samples have been prepared varying the concentration of the activating agent (H(3)PO(4)) and the treatment temperature. The yield of the process decreases with increasing phosphoric acid concentrations. Furthermore, high concentrations of activating agent lead to mainly mesoporous activated carbons to the detriment of the microporous texture. Treatment temperatures up to 450 degrees C lead to a progressive increase of the micro- and mesopore volumes. Values of specific surface area (S(BET)) as high as 1723 m(2) g(-1)have been obtained using appropriate phosphoric acid concentrations and treatment temperatures. The samples prepared have been successfully used in the removal of Zn(II) from aqueous solutions. From the adsorption kinetic data it may be stated that the equilibrium time is, in all cases, below 170 h. The adsorption process as a rule becomes faster as the mesopore volume and specific surface area of the samples increase. The adsorption isotherms in liquid phase point out that the adsorption capacity (n(0)(s)) and the affinity towards the solute (K(ci)) are higher for the sample showing the most developed mesoporous texture and surface area as well.     

HCl浓度对水合氧化铁复合吸附剂P吸附效能的影响

为避免传统水合氧化铁(HFO)负载树脂复合吸附剂制备过程中大量使用HCl对设备防腐、安全及环保带来的问题,优化HFO复合吸附剂的制备工艺方法,改变负载液中HCl浓度制备得到多种HFO复合吸附剂,考察制备得到的HFO复合吸附剂对P的吸附动力学、吸附等温线、初始pH、共存离子影响、解吸再生方法等,评价负载液中HCl浓度对吸附剂吸附效能的影响。结果表明,负载液中HCl浓度由2 mol·L?1降低至0.5 mol·L?1,并不会显著降低HFO复合吸附剂的P吸附容量。HCl浓度为0.5 mol·L?1时制备得到的HFO复合吸附剂对P的最大吸附容量为29.67 mg·g?1,显著高于D201树脂载体(16.39 mg·g?1),其吸附动力学曲线更符合准一级吸附动力学模型,最佳的P吸附pH为6~8,在共存离子Cl?、NO₃?、SO₄2?、CO₃2?浓度为1.0 g·L?1的条件下,吸附剂对P的吸附容量降低31.1%~53.0%。采用5wt%的NaOH溶液能有效实现吸附剂中P的解吸再生。      

Arsenic speciation in rice and soil containing related compounds of chemical warfare agents

Diphenylarsinic acid, phenylarsonic acid, methylphenylarsinic acid (MPAA), dimethylphenylarsine oxide (DMPAO), and methyldiphenylarsine oxide (MDPAO) in soil and rice were extracted, separated by reversed-phase chromatography, and quantified by ICPMS with a membrane desolvating system. For the extraction of arsenicals from rice grain and straw, 68% HNO3 provided better extraction efficiency than water, 50% methanol, or 2.0 mol L(-1) trifluoroacetic acid. For the extraction from soil, 68% HNO3 provided better extraction efficiency than H2O, 1 mol L(-1) H3PO4, or 1 mol L(-1) NaOH. The contaminated soil contained all five aromatic arsenicals along with inorganic arsenicals as main species (5.86 +/- 0.19 microg of As kg(-1): 60.8 +/- 2.0% of total extracted As). After pot experiments, rice straw contained mainly DMPAO (7.71 +/- 0.48 microg of As kg(-1): 60.5 +/- 3.7%), MDPAO (0.91 +/- 0.07 microg of As kg(-1): 7.2 +/- 0.5%), and inorganic As (2.85 +/- 0.20 microg of As kg(-1): 22.3 +/- 1.6%). On the other hand, rice grain contained mainly MPAA (1.17 +/- 0.04 microg of As kg(-1): 86.7 +/- 2.7%). The root uptake of each species from the soil and transport from straw to grains were significantly related to the calculated log K(ow) values.