超声辅助碱浸铜冶炼烟灰中铜砷分离

采用超声辅助Na₂S-NaOH浸取体系对铜冶炼烟灰进行研究,在NaOH、Na₂S与烟灰质量比0.4：1,液固比20：1,反应温度75℃,反应时间5 min,超声功率80 W,搅拌速率400 r·min^-1条件下,As浸出率为88.81%,Cu浸出率为0.025%,实现了Cu和As的有效分离。采用该方法处理后,与单独碱浸相比,As浸出率提高9.21%,烟灰中As含量由0.85%降至0.58%,Cu含量由2.21%增至2.30%,且As浸出毒性浓度由12.66 mg·L^-1降至2.84 mg·L^-1,为烟灰的资源化利用创造了条件。超声辅助碱浸除砷动力学满足收缩核混合反应控制模型,表观活化能0.114 kJ·mol^-1。XRD、XPS和重金属形态分析结果表明,超声空化作用可使As（Ⅲ）氧化为As（Ⅴ）,有利于As浸出,故超声过程强化有利于Cu和As在碱浸体系中的选择性分离。     

辉光放电等离子体辅助碱浸铜冶炼烟灰中铜砷分离

采用辉光放电等离子体辅助Na_2S-NaOH浸取体系对铜冶炼烟灰(简称"烟灰")进行研究,在放电时间10min、放电功率500 W、放电压强150 Pa、极板间距0.9 cm的条件下,砷的浸出率为92.52%,铜的浸出率为7.76%,实现了砷和铜的有效分离。采用该方法处理后烟灰中的砷从7.11%降到0.45%,铜从2.62%变为2.42%,为烟灰的进一步利用创造了条件。XPS、XRD和重金属形态分析的综合分析结果表明,辉光能将As(Ⅲ)氧化为As(Ⅴ)、Cu(Ⅰ)氧化为Cu(Ⅱ),且在碱性条件下As(Ⅴ)比As(Ⅲ)更易浸出。因此,辉光放电预氧化有利于砷和铜在碱浸体系中选择性分离。     

超声辅助碱浸铜冶炼烟灰中铜砷分离

采用超声辅助Na_2S-NaOH浸取体系对铜冶炼烟灰进行研究,在NaOH、Na_2S与烟灰质量比0.4:1,液固比20:1,反应温度75℃,反应时间5 min,超声功率80 W,搅拌速率400 r·min~(-1)条件下,As浸出率为88.81%,Cu浸出率为0.025%,实现了Cu和As的有效分离。采用该方法处理后,与单独碱浸相比,As浸出率提高9.21%,烟灰中As含量由0.85%降至0.58%,Cu含量由2.21%增至2.30%,且As浸出毒性浓度由12.66 mg·L~(-1)降至2.84mg·L~(-1),为烟灰的资源化利用创造了条件。超声辅助碱浸除砷动力学满足收缩核混合反应控制模型,表观活化能0.114 kJ·mol~(-1)。XRD、XPS和重金属形态分析结果表明,超声空化作用可使As(Ⅲ)氧化为As(Ⅴ),有利于As浸出,故超声过程强化有利于Cu和As在碱浸体系中的选择性分离。     

溶液中辉光放电等离子体化学反应研究

分析了溶液中辉光放电等离子体过程中水分子在等离子体层、等离子体-溶液界面和主体溶液中的反应历程;介绍了水溶液体系中辉光放电等离子体电解引发的等离子体合成反应和高级氧化反应;对有机溶剂体系中的辉光放电等离子体电解反应进行了介绍.实验表明甲醇溶液辉光放电等离子体电解主要产物是氢气,还有少量一氧化碳、甲烷、乙烷、丙烷、1,3,5-三(口恶)烷和水等,气相产物中氢气摩尔分数在86%以上.根据甲醇溶液中GDE过程中得到的产物分析,提出了甲醇分解的可能反应历程.     

EDTA滴定法测定铜冶炼烟灰中的铅

本文建立了铜冶炼烟灰中铅量的分析方法。样品经氟化氢铵—盐酸—硝酸—高氯酸—硫酸—氢溴酸溶解,在此条件下,砷和锑可以被挥发除去,过滤硫酸铅,沉淀连同滤纸一起在乙酸-乙酸钠缓冲体系溶解,加少许抗坏血酸,三滴二甲酚橙指示剂,2mL巯基乙酸（1+99）,EDTA络合滴定法测定铜冶炼烟灰中的主量铅,滤液中铅量用电感耦合等离子体发射光谱法来进行补正。本文从溶样方式、沉淀条件、乙酸-乙酸钠缓冲溶液的加入量实验、铋干扰消除实验、滤液中铅量的补正实验等多个方面进行研究,选择合理条件范围和消除干扰方法。本实验选取3个样品,将铅铋连续滴定测得铅量和本实验测定铅量进行比对,验证本实验的正确度,加标回收率在99.0～101.5之间,精密度良好,准确度高。     

铜冶炼烟尘酸性浸出液中铜、砷分离行为研究

针对铜烟尘酸性浸出液中砷与有价金属分离的难题,采用加压合成臭葱石的方法,实现Cu和As的高效分离以及将砷以臭葱石的形式进行稳定固化的目的。在加压体系下研究了温度、总压和初始pH值对Cu和As的分离效果以及臭葱石合成的影响。结果表明：提高反应温度,有利于Cu和As的分离及合成晶型良好的臭葱石,温度较低时生成铁矾影响臭葱石合成进而影响Cu、As的分离;初始pH值增大,不利于Cu和As的分离,初始pH值越高,体系中的Fe³⁺越易水解,不利于臭葱石的合成,进而影响Cu和As的分离效率;总压增大,有利于Cu和As分离,不利于臭葱石的稳定固化,氧压过高氧化速率加快,易发生Fe³⁺水热水解反应,臭葱石形貌由双锥状变为团聚状使其稳定性降低。在初始Fe和As物质的量之比1.2、初始pH值0.4、时间2 h、初始铜离子浓度9 g·L^-1、总压0.8 MPa、温度160℃的条件下,As和Cu的沉淀率分别为81.57%与12.27%,Cu、As分离系数为76.88,能够高效分离Cu和As,并获得晶态臭葱石。     

辉光放电等离子体处理有机废水研究进展

辉光放电是一种环境友好的、新兴的电化学高级氧化技术,等离子体是由电极与其周围的电解液产生直流辉光来维持。本文综述了辉光放电等离子体在生物难降解有机废水处理方面的实验装置、特点及机理,介绍了辉光放电等离子体技术的国内外研究现状,探讨了该技术在有机废水处理中存在的问题及其应用前景。     

辉光放电等离子体对农药毒性的消除作用

研究了辉光放电等离子体在不同酸度、不同温度和催化剂存在时对水体中农药克百威、甲基对硫磷毒性的消除作用。结果表明,在直流电压为600V,电流范围为145～155mA的条件下产生辉光放电等离子体处理两种农药水溶液,溶液的毒性降低,弱酸弱碱条件毒性降低更快,Fe2+的催化有利毒性降低,高温对去除毒性不利。     

辉光放电等离子体处理有机染料直接黑EX废水

辉光放电电解是一种新型的产生等离子体的电化学方法。在惰性电解质水溶液中进行辉光放电电解,可以产生大量的.OH、.H、e-aq、HO2.等活性粒子,且产物的总生成量超过了根据法拉第定律计算的产量,每通过1 mol电子可生成12 mol.OH。.OH氧化能力非常强,可以无选择地降解各种有机物。文章探讨了电压、初始浓度、pH、催化剂Fe2+等因素对辉光放电降解直接黑EX效果的影响。用紫外可见吸收光谱检测了染料的降解过程。实验表明:利用该方法可以使水中染料大部分降解。直接黑EX优化降解条件为:工作电压610 V,pH 3.12,Fe2+催化作用下降解效率明显提高。     

辉光放电电解等离子体处理次甲基蓝废水

利用辉光放电电解等离子体技术对次甲基蓝废水的降解进行了研究,详细考察了电压、染料浓度、pH值、催化剂对次甲基蓝降解效果的影响。实验发现,次甲基蓝废水的优化降解条件为:工作电压610 V,pH值3.0,Fe2+催化作用下降解效率明显提高。利用紫外-可见吸收光谱监测了次甲基蓝的降解过程,结果表明,次甲基蓝先被降解成小分子,小分子继而被进一步降解。     

铜冶炼电收尘灰浸出液与硫化砷渣综合处理工艺研究

介绍了一种铜冶炼电收尘灰酸浸液与硫化砷渣的联合处理工艺。确定了铜冶炼电收尘灰浸出液与硫化砷渣最佳反应条件为:加入硫酸铜量为理论铜与砷摩尔比1.1∶1,反应温度85℃,反应时间2 h,铜离子质量浓度15 g/L,初始硫酸质量浓度30 g/L。     

铜冶炼电收尘烟灰浸出渣脱砷工艺研究

研究了采用双碱法脱除铜冶炼电收尘烟灰浸出渣中砷的新工艺,通过考察浸出剂浓度、浸出时间、浸出温度、液固比单因素条件实验,得到了最优工艺条件：NaOH用量为理论量的1.1倍、液固比（mL/g）为4∶1、浸出温度为60 ℃、浸出时间为2 h。在此条件下,电收尘烟灰中砷的浸出取得了较好的效果,砷的浸出率达到90％以上。通过净化得到的砷酸钠纯度在95%以上。     

Selective removal of arsenic from arsenic-containing copper dust by low-temperature carbothermal reduction

ABSTRACT

To selectively separate arsenic from arsenic-containing copper dust, this paper reports a new method of treating the dust by carbothermal reduction and roasting it with coke powder at low temperatures. The effects of different roasting temperatures, coke powder additions and roasting times are discussed. Optimum conditions were obtained to selectively separate arsenic from other valuable metals. The volatilization rate of arsenic was 97.02% and the content of arsenic in the slag was 0.31%. Other valuable metals were not volatile under the conditions of a 350°C roasting temperature, coke powder addition of 30%wt, coke powder particle size of 0.15–1 mm, and a roasting time of 150 min.     

液下辉光放电等离子体重整低碳醇水溶液制氢

探讨了阴极液下辉光放电等离子体重整低碳醇水溶液制氢反应过程.比较了水溶液和低碳醇水混合溶液中阴极等离子体重整制氢实验,发现以低碳醇水溶液为等离子体重整介质时,低碳醇分子在阴极等离子体层中表现出明显高于水分子的反应活性,阴极气体单位体积能耗可以降至2.690×10³ kJ•m^-3,生成气体中氢气含量达95％,并有一氧化碳和二氧化碳.分析了电压对阴极生成气单位体积能耗和气体组成的影响,发现电压越高等离子体密度越大,阴极生成气单位体积能耗降低,被等离子体分解的溶剂溶质分子也越多.比较了不同浓度低碳醇溶液的产气情况,低碳醇浓度对生成气组成和单位体积能耗有重要影响.     

Use of high temperature and high humidity to test the adhesion of sputtered copper to a polyimide surface modified by an AC nitrogen glow discharge

We have used an extreme environmental stress test to study the adhesion of a thin sputtered copper film (0.5 μm) to flexible polyimide (PI) substrates between 25 and 125 μm thick. The polyimide types include Kapton (PMDA-ODA) and Upilex (BPDA-PDA). When there was no surface modification on the PI, the adhesion of the film to Upilex type S was better than the adhesion to Upilex type R or Kapton type HN. When the polymer surface was treated with a simple AC nitrogen glow discharge (NGD), there was an improvement in the adhesion of the film to each of these polyimides. This improvement in adhesion became apparent after the film/substrate combination was subjected to either boiling water or steam for 30 min or more; the difference became quite clear after 2 h. A simple tape test was used to quickly estimate a relative adhesion strength. In order to compare the effect of our AC NGD treatment with other substrate surface modification methods, we used it to improve the coupling of a thick (> 10 μm) layer of copper (via a thin intermediate chromium layer) to a rigid PI substrate, formed from spin coating its precursor onto a silicon wafer. Peel test results were within a factor of 2-3 of the corresponding results obtained with a radio frequency (RF) plasma and ion beam treatments.     

常压辉光放电等离子体研究进展及聚合物表面改性

综述了常压辉光放电等离子体(APGDP)的产生机理及研究进展。介绍了难以产生稳定的APGDP 是由于辉光放电容易向细丝放电和弧光放电过渡,其解决措施是选择合适的介质板材料、电极间距、电源电压及频率、气体成分等。指出APGDP对化纤聚合物表面改性的效果与聚合物的分子结构、等离子体气体、介质板材料等因素有关,且改性效果具有时效性,要根据聚合物的分子结构选择合适的等离子体。     

纳米二氧化钛薄膜协同接触辉光放电技术降解亚甲基蓝

通过溶胶-凝胶法制得纳米TiO_2薄膜,研究了日光条件下亚甲基蓝在薄膜上的光催化降解以及在TiO_2协同接触辉光放电条件下的降解,结果表明:镀膜5次所得薄膜具有高的催化性能;TiO_2协同接触辉光放电可以高效地降解亚甲基蓝分子;所制得的薄膜随使用次数的增加而活性变化不大。     

Surface characterization and antibacterial activity of chitosan‐grafted poly(ethylene terephthalate) prepared by plasma glow discharge

Poly(ethylene terephthalate) (PET) texture was exposed to oxygen plasma glow discharge to produce peroxides on its surfaces. These peroxides were then used as catalysts for the polymerization of acrylic acid (AA) in order to prepare a PET introduced by a carboxylic acid group (PET‐A). Chitosan and quaternized chitosan (QC) were then coupled with the carboxyl groups on the PET‐A to obtain chitosan‐grafted PET (PET‐A‐C) and QC‐grafted PET (PET‐A‐QC), respectively. These surface‐modified PETs were characterized by attenuated total reflection Fourier transform IR spectroscopy, electron spectroscopy for chemical analysis, and a contact angle goniometer. The amounts of AA, chitosan, and QC grafted on the PET surfaces as determined by the gravimetric method were about 6, 8, and 9 μg/cm², respectively. The antibacterial activity of the surface‐modified PET textures was investigated using a shake flask method. After 6 h of shaking, the growth of bacteria was markedly inhibited by PET with ionically (86% in PET‐A^?‐C⁺) and covalently (75% in PET‐A‐C) grafted chitosan and with covalently grafted QC (83% in PET‐A‐QC). After the laundering the inhibition of the growth of the bacteria was maintained in the range of 48–58%, showing the fastness of the chitosan‐grafted PET textures against laundering. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2769–2778, 2001     

Separation of As and Bi and enrichment of As,Cu, and Zn from copper dust using an oxidation-leaching approach

Copper dust with high arsenic content is a hazardous waste that should be treated properly. Herein, the copper dust is oxidized, leached, and separated at room temperature and atmospheric pressure. To separate As and Bi, part of As(Ⅲ) in copper dust is oxidized to As(V), so that most of the As, Cu, and Zn elements enter the solution and the Bi remains in the leaching residue. Also, the influence of several factors,such as H_2 SO_4 dosage, H_2 O_2 dosage, liquid–solid ratio, leaching temperature and leaching time, on the leaching percentage of As, Bi, Cu, and Zn is systematically investigated. The optimal conditions are obtained as follows: liquid–solid ratio of 3:1, H_2 O_2 dosage of 10 ml/50 g(dust), H_2 SO_4 dosage of4.5 ml/50 g(dust), leaching temperature of 85 °C, and leaching time of 3 h. Under these conditions,the leaching percentage of As, Cu, Zn, and Bi is found to be 97.39%, 96.11%, 97.32%, and 2.40%, respectively. For further recovery of As from the leaching solution, the one-step recycle leaching of the leaching solution is performed to increase the concentration of As in the recycled leaching solution. The concentration of arsenic in the recycling leaching solution is found to be 79.63 g·L~(–1), which is beneficial for the study on further recovery of As_2 O_3.