电镀废水中铜的回收方法

氰化镀铜废水在破氰时铜离子转化成碱式碳酸铜细小沉淀物颗粒,需要加入大计量的助凝剂吸附,然后再加絮凝剂才能使其沉淀分离,处理成本较高。在破氰时用石灰代替烧碱调节pH,破氰产生的二氧化碳与氧化钙反应生成碳酸钙大颗粒沉淀,碱式碳酸铜与碳酸钙共沉积,解决了沉淀分离困难的问题。用石灰处理焦磷酸盐镀铜废水,氧化钙能与焦磷酸根反应生成焦磷酸钙沉淀,同时氧化钙又与铜离子反应生成氢氧化铜,从而实现铜的回收。用石灰处理焦铜电镀废水,可实现达标排放。     

钢铁件HEDP直接镀铜工艺开发30年回顾 第三部分——HEDP及其他碱性镀铜液的废水处理

比较了几种碱性无氰镀铜螯合剂的环保特性与废水处理难度,分析了氧化破坏法、化学沉淀法和离子交换法处理螯合废水的优缺点,介绍了从碱、酸铜废水中回收铜粉以及HEDP镀铜液除铜和除HEDP的高效沉淀新技术.     

以L—半胱氨酸为掩蔽剂配位滴定法测定铜

在弱酸性溶液中,Ｌ－半胱氨酸与铜（Ⅱ）形成无色可溶性配合物,其稳定性高于相对应的乙二胺四乙酸（ＥＤＴＡ）配合物。在铜（Ⅱ）的ＥＤＴＡ配合物溶液中加入掩蔽剂Ｌ－半胱氨酸,则配合物分解。通过以铅（Ⅱ）标准溶液滴定释放出的ＥＤＴＡ,可测定铜（Ⅱ）的含量。     

重金属捕集剂研究进展

随着印刷线路板(Printed Circuit Board,PCB)行业的不断发展,印刷线路板废水所带来的水污染问题越来越严重。铜离子及络合铜离子是印刷线路板废水中的特征污染物。为此,迫切需要研究开发水中铜离子及络合铜离子去除技术。其中,使用重金属捕集剂与废水中铜螯合反应后沉淀是废水除铜的主要方法之一。文章介绍重金属捕集剂研究进展。     

去除农药废水中铜、锌离子的方法研究

研究了NaOH、Na2S沉淀法和微电解-沉淀絮凝法去除农药废水中的铜、锌离子。探讨了三种处理方法的控制因素及其对铜、锌离子去除效果的影响。最终确定处理方案为：调节含铜、锌废水pH值为8后,每升废水分别加入Na2S0.59g和0．48g,处理后溶液中铜、锌离子含量分别为6mg／L和1mg／L,可进入生化配水池稀释10倍后,铜、锌离子含量均小于1mg／L,对微生物降解无影响,达到排放标准。     

用亚铁离子和钙离子协同沉淀柠檬酸盐镀镍废水中的配位剂

研究了亚铁离子和钙离子沉淀含羧基配位剂时的协同效应。在pH为10.5~12.5的条件下,用亚铁离子和钙离子共同沉淀柠檬酸盐镀镍废水中的配位剂,并令从配合物中释放出来的镍离子生成氢氧化镍沉淀。本方法简单、快速、成本低,出水的总镍、总铁和化学需氧量能至少达到《电镀污染物排放标准》(GB 21900–2008)的"表2"要求。     

以L—半胱氨酸为掩蔽剂配位滴定法测定铜

在弱酸性溶液中，Ｌ－半胱氨酸与铜（Ⅱ）形成无色可溶性配合物，其稳定性高于相对应的乙二胺四乙酸（ＥＤＴＡ）配合物。在铜（Ⅱ）的ＥＤＴＡ配合物溶液中加入掩蔽剂Ｌ－半胱氨酸，则配合物分解。通过以锅（Ⅱ）标准溶液滴定释放出的ＥＤＴＡ，可测定铜（Ⅱ）的含量。     

镀镍废水中氰化物的处理方法

用漂水处理含镍废水中的氰化物,由于生成氢氧化高镍沉淀,次氯酸钠利用率太低,方法不可行。用双氧水破氰效果较好,但过量的双氧水分解后产生氧气,使氢氧化镍沉淀上浮,给沉淀分离带来了困难,用焦亚硫酸钠还原过量的双氧水,能够有效地解决这个问题。加氢氧化钠将废水pH控制在10左右,既可使镍离子完全沉淀,又可以使双氧水破氰反应顺利进行。实践证明,用这种方法处理含镍废水中的氰化物,氰、镍和铜离子的质量浓度能够达到国家排放标准的要求。     

木犀草素铜配合物的制备及其对DNA的裂解作用研究

木犀草素金属配合物具有多种生物活性。本实验以木犀草素为原料与新戊酸铜、苯甲酸铜反应,制得木犀草素铜配合物;通过红外、紫外光谱等方法对配合物分析其化学组成;采用凝胶电泳法研究配合物对DNA的裂解能力。实验表明,木犀草素与两种铜盐反应生成相同产物,新戊酸根和苯甲酸根未参与到配合物的形成中,紫外谱图显示木犀草素4-CO和5-OH与铜离子发生配位。两种方法生成的配合物对DNA的裂解能力较木犀草素均有显著提升。     

Ca~(2+)强化沉淀处理含铜电镀废水并回收铜研究

针对氢氧化物沉淀工艺不能去除络合态重金属的问题,采用加钙离子强化氢氧化物沉淀的方法处理含铜电镀废水并回收铜实验。结果表明,钙离子的加入能够有效提高氢氧化物对络合态重金属废水的处理效果。当pH 10,反应时间为15 min,除铜效果为佳,铜去除率可达99%以上。与现有铁氧体法相比,钙强化氢氧化物沉淀法投药量大大减少,工艺稳定性也大大增加。把沉泥加入pH5的酸液中,铜离子可实现循环利用,为保证重金属回收率,其反应时间应大于30 min。该方法具有工艺简单、成本低廉、效果明显和易于管理的特点。     

氯化钾镉钴合金电镀废水的组合处理方法

在pH为10~12的条件下,先用亚铁离子和钙离子共同沉淀氯化钾镉钴合金电镀和钝化混合废水中的氨三乙酸等羧酸配位剂,六价铬被亚铁离子还原成三价铬后与镉离子、钴离子等一同生成氢氧化物沉淀。再用二甲基二硫代氨基甲酸钠沉淀废水中残留的重金属离子,使其沉淀完全。最后用次氯酸钠氧化废水中的电镀添加剂,降低其化学需氧量(COD)。该方法成本低,处理结果可满足GB 21900-2008《电镀污染物排放标准》的“表3”要求。     

Study of anodic layers and their effects on electropolishing of bulk and electroplated films of copper

Copper anodic layers in solutions of hydroxyethylidenediphosphonic acid (HEDP), phosphoric acid, and phosphoric acid with organic and inorganic additives were analysed in situ using electrochemical impedance spectroscopy (EIS). Salt films formed in HEDP solutions were detected. No salt film was found in solutions of phosphoric acid or phosphoric acid with copper oxide, ethylene glycol and sodium tripolyphosphate as additives. Analysis of EIS data suggests that H₂O molecules are the mass transport controlling species in solutions of phosphoric acid and of phosphoric acid with copper oxide, whereas Cu²⁺ ions are the mass transport controlling species in solutions of HEDP and of phosphoric acid with additives ethylene glycol and sodium tripolyphosphate. Very good results for electropolishing of bulk copper discs were obtained in all the above solutions, but the electropolishing of electroplated copper films on patterned silicon wafers is more challenging. In this case, good planarization was obtained only from HEDP solutions. Experimental results and theoretical analysis indicate that surface profile of anodic layers is an important factor influencing planarization of electroplated copper films on patterned silicon wafers. An electrically resistive anode film with macro surface profile can lead to planarization of the gentle surface undulations of electroplated copper films on trenched silicon wafers due to migration smoothing, diffusion smoothing, and ohmic levelling effects.     

Combined use of chitosan and alginate in the treatment of wastewater

This study examined the combined use of chitosan and sodium alginate in the treatment of wastewater containing heavy‐metal ions and dye. Wastewater samples were divided into two equal parts before chitosan and sodium alginate solutions were added to each part. When these two solutions were mixed together, the heavy‐metal ions and dye molecules were separated from the water as the positively charged chitosan and the negatively charged sodium alginate precipitated each other. The effects of the concentration and ratio of chitosan and sodium alginate, the treatment temperature, and the time on the efficiency of metal‐ion and dye removal were investigated. The results showed that when used in combination, sodium alginate and chitosan were effective in removing copper, cadmium, lead, and silver ions as well as acid dye molecules © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3581–3587, 2007     

QHS-3型钠钙浮选剂用催化剂生产过程中含铜、镍离子废水的处理

对QHS-3型钠钙浮选剂用催化剂生产过程中产生的含铜、镍离子废水采用常规中和沉淀法与加入金属螯合剂M相结合的方法进行了去除铜、镍离子的研究,结果表明:在最佳工艺条件下,即在溶液的pH值为9.2,聚丙烯酰胺(PAM)加入量为6 mg/L,金属螯合剂M投加量为80～90 mg/L时,处理后的废水中的铜、镍离子的质量浓度达到了国家排放标准.     

Gelcasting of silicon carbide based on gelation of sodium alginate

A novel gel-casting process by sodium alginate gelation is presented. Solidified agent and chelator are added into sodium alginate solution simultaneously, thus the gelation between calcium ions and sodium alginate is avoided in this stage due to the chelate complex formed from the chelator and solidified agent (calcium salt). By adding hexanedioic acid, free calcium ions are released from the chelate complexes and react with sodium alginate, forming a three-dimensional network. Therefore, silicon carbide particles are held in this three-dimensional network and the slurry is consolidated. Green body with bending strength of 3 MPa, perfect surface and homogeneous microstructure has been produced by this process.     

羟基乙叉二膦酸(HEDP)对碳酸钙晶体生长过程影响的原子力显微镜(AFM)研究

用原子力显微镜 (AFM)观测了添加羟基乙叉二膦酸 (HEDP)后的碳酸钙晶粒的表面形貌变化。纯碳酸钙过饱和溶液析出的碳酸钙晶体有两种主要的形态 :薄片状菱形晶体和类似立方体的菱方体晶体。AFM图像显示添加HEDP后菱方体晶体的形貌发生了根本性的变化 ,呈现一种类似多晶的表面结构 ;而薄片状菱形晶体在添加HEDP前后测量不到生长变化。实验结果表明HEDP对薄片状菱形晶体有阻垢效果 ,而对菱方体晶体的生长无抑制作用或较差     

酸性废水体系中硫酸钙反应结晶过程研究(英文)

The present work focused on the recycle of the sulfate and the metal ions from acidic wastewater dis charged by nonferrous metallurgical industry. The effects of the temperature, the reactant concentration, the stirring speed and the metal ions on the reactive crystallization process of calcium sulfate between sulfuric acid and lime were systematically investigated. The morphology of the precipitated crystals evolved from plateletlike and nee dlelike shape to rodlike shape when the temperature was increased from 25 to 70 ℃. An increase in the agglom.     

Study of copper electrodeposition mechanism from a strike alkaline bath prepared with 1-hydroxyethane-1,1-diphosphonic acid through cyclic voltammetry technique

Copper strike baths are extensively used in metal plating industry as they present the ability to plate adherent copper layers on less-noble metal substrates such as steel and zinc die castings. However, in the last few years, due to environmental controls and safety policies for operators, the plating industry has been interested in replacing the toxic cyanide copper strike baths with environmentally friendly baths. A broad bibliographic review showed that the published papers, referring to the new nontoxic copper strike baths, are patents, having little or no emphasis focused on electrodeposition mechanisms. Therefore, it was decided to study the copper electrodeposition mechanism from a strike alkaline bath prepared with one of the most nontoxic chelating agents cited in many patents which is the 1-hydroxyethane-1,1-diphosphonic acid, known as HEDP. This acid forms very stable water soluble complexes with Cu²⁺ ions, thus cupric sulfate was used for preparing the plating bath. The results obtained through a cyclic voltammetry technique showed that Cu²⁺ ion reduction to Cu from an HEDP electrodeposition bath occurs via a direct reduction reaction without a formation of Cu⁺ intermediates.