五价锑在脱除铜电解液中砷、锑、铋杂质中的作用(英文)

通过向含有45 g/L Cu2+、185 g/L H2SO4、10 g/L As和0.5 g/L Bi的铜电解液中加入Sb(V),研究五价锑对铜电解液中砷、锑、铋杂质脱除作用机理。过滤电解液,采用化学分析、SEM、TEM、EDS、XRD、FTIR等方法对沉淀渣的结构形貌和成分进行表征。结果表明,沉淀渣呈尺寸为50~200μm的不规则块状,其化学成分主要为砷、锑、铋和氧。红外光谱检测表明,沉淀渣主要特征官能团为As—O—As、As—O—Sb、Sb—O—Bi、Sb—O—Sb和Bi—O—Bi。X射线衍射和电子衍射检测结果表明,沉淀渣由AsSbO4、BiSbO4和Bi3SbO7组成。锑酸盐的生成是五价锑脱除铜电解液中砷、锑、铋杂质的主要原因。     

铜电解液净化中铜砷的分离与回收(英文)

经二氧化硫还原、蒸发结晶,使铜电解液中铜、砷、锑和铋得到有效去除。结晶产物经过溶解、氧化、中和、沉淀、过滤和蒸发结晶,得到三氧化二砷和硫酸铜。当采用SO2将铜电解液中As(Ⅴ)充分还原为As(Ⅲ),并加热蒸发浓缩铜电解液中硫酸浓度至645g/L时,铜电解液中铜、砷、锑和铋的去除率分别为87.1 %,83.9 %,21.0 %和84.7%。在温度30℃,将65g结晶产物溶于200mL自来水时,砷的去除率为92.81%。将所得滤液在如下条件下净化:n(Fe):n(As)为1.2,双氧水为理论用量的19倍,氧化温度为45℃,氧化时间为40min,终点pH为3.7,净化后蒸发浓缩结晶,所得硫酸铜溶液中硫酸铜含量达到98.8%。     

铜电解液中铜的快速自动分析

研究了铜电解液中高含量铜的光度分析。直接利用水合铜离子的蓝色，双波长扣除试样浑浊干扰；标样以硫酸为介质消除硫酸根干扰；于标样中加入定量的镍，并选择适当的波长克服镍的干扰。实现了贵溪冶炼厂铜电解液中铜（３０～６０ｇ／Ｌ）的自动快速分析，２４０次进样／ｈ，结果令人满意     

二段脱铜液还原结晶法脱砷新工艺

对铜电解液脱砷方法进行研究,提出以二段脱铜液为原料,采用SO2还原结晶法脱砷新工艺。在二段脱铜液中通入SO2,将其中的As(Ⅴ)还原成As(Ⅲ),还原后的溶液通过蒸发结晶析出As2O3,达到二段脱铜液脱砷的目的。结果表明:当As(Ⅴ)浓度为12.41 g/L、H2SO4浓度为253.00 g/L、反应温度为60℃时,向二段脱铜液中通入SO290 min后静置90 min,二段脱铜液中As(Ⅴ)的还原率达到94.54%。还原后的溶液进行蒸发结晶,当蒸发前与结晶后的体积比(V0:V1)为3.5时,砷的脱除率达到91.33%,结晶产物为As2O3。与传统脱砷工艺相比,新工艺具有操作简单、成本低廉及砷的脱除效果明显等优势。     

控制阴极电势电积法脱铜砷

在净化铜电解废液工艺流程中，控制阴极电势值，使铜砷优先析出，并抑制氢气与砷化氢的析出，以达到净化电解液的目的。控制阴极电势脱铜砷电积法的脱铜电流效率达到８０％以上，电积后液中铜含量小于０．５ｇ／Ｌ，砷含量小于１ｇ／Ｌ，该方法具有节能与环保双重效益。     

含砷钴镍渣中砷提取与砷盐制备的资源化利用(英文)

对某厂硫酸锌溶液砷盐净化工艺产生的含砷钴镍渣进行砷提取与资源化利用研究。基于含砷钴镍渣中砷的存在形态并利用砷的两性特性,考察碱介质氧压浸出砷的方法,确定并优化氧气气氛下碱介质浸出砷的最佳条件。结果表明,在溶出温度140℃、碱介质NaOH浓度150 g/L、氧压0.5 MPa、液固比5∶1的条件下,砷的浸出率达到99.14%。根据As_2O_5、ZnO和PbO在NaOH溶液中的溶解特性,提出采用富砷浸出液直接冷却结晶分离获得砷酸钠晶体的砷分离-碱介质循环的方法,且富砷浸出液直接在25℃下的结晶率达88.9%;根据氧化还原电位,将砷酸钠晶体溶解获得的溶液直接采用SO_2气体进行还原来制备三价砷盐,在一定条件下砷的还原率达92%,从还原液可制得正八面体结构的As_2O_3晶体循环或将还原液直接循环回用于硫酸锌溶液砷盐的净化系统。利用含砷钴镍渣中砷的氧压碱介质浸出-浸出液冷却结晶—砷酸钠溶液SO_2气体还原-As_2O_3晶体制备的技术路线可实现含砷钴镍渣中砷的提取与资源化利用。     

不同喷吹气体对铜冶炼熔渣中砷气化脱除的影响（英文）

为了减少铜熔炼渣中砷所带来的环境问题,提出一种基于气体喷吹脱除熔融铜渣中砷的方法,期望在铜回收工艺前将铜熔炼渣中的砷尽可能以粉尘的形式富集。对比惰性气体、氧化性气体和还原性气体对熔渣中砷脱除的影响。氧化性气体CO₂氧化夹杂冰铜中的砷及砷硫化物,并充当气体载体将砷氧化物带出熔池。还原性气体CO可以将FeO_x-SiO₂熔渣中的砷氧化物还原,并使其挥发至气相,可以实现60%以上的砷脱除率。该研究为熔炼渣中砷脱除提供指导。     

湿法炼锌铜砷渣分离提铜及沉砷工艺研究

采用铁粉置换法处理湿法炼锌产生的锌浸渣还原浸出液,产出一种含砷铜渣,以该含砷铜渣为研究对象,利用氧压酸浸缓慢分解含砷铜渣,使其中的铜、锌等溶解进入溶液,同时,砷、铁以臭葱石的形式沉淀为浸出渣,从而将铜的浸出和砷、铁的沉淀在同一反应釜同一过程中完成,有效实现含砷铜渣中有价金属的浸出过程与杂质的沉淀过程在同一过程同步进行。结果表明：在反应温度为135℃、反应时间为4 h、液固体积质量比25 mL/g、硫酸浓度为50 g/L、氧分压500 kPa、铁砷摩尔比为1的条件下,浸出渣中铜含量仅为2.03%,浸出率达到97.72%,砷含量达到26.06%,沉淀率达到95.98%;浸出液中铜的浓度达到20.47 g/L,砷浓度小于0.63 g/L,实现了铜和砷的高效分离,提高了铜金属回收率和资源综合利用率。浸出渣中砷均以臭葱石(FeAsO₄·2H₂O)的形式存在,符合当前的环境友好型发展理念。     

次氧化锌中砷的物相及砷的浸出(英文)

研究烟化炉次氧化锌中砷的物相类型。结果表明:按砷的物相可将次氧化锌分为3种类型。在一型次氧化锌中砷以As2O3形态存在,而在二型和三型次氧化锌中砷分别以亚砷酸锌(Zn(AsO2)2)和砷酸铅(Pb(As2O6),Pb4As2O9)形态存在。在热力学分析基础上,对二型次氧化锌进行浸出脱砷。结果表明:采用30g/LNaOH溶液,在液固比3、温度20°C的条件下,砷的浸出率在1h内可达到65%～70%,而铅、锌的损失均小于1%。     

硫酸镍铵复盐结晶法分离回收铜电解液中的镍（英文）

研究采用硫酸镍铵复盐结晶从铜电解液中分离回收镍的方法。研究发现,在相同温度的溶液中,硫酸铜的溶解度小于硫酸镍的溶解度,而硫酸铜铵的溶解度大于硫酸镍铵的溶解度。因此,加入(NH₄)₂SO₄可使铜电解液中的镍选择性结晶析出。按(NH₄)₂SO₄/NiSO₄摩尔比≤0.8加入(NH₄)₂SO₄,在-15℃冷冻结晶10 h,可使其中的镍以Ni(NH₄)₂(SO₄)₂·6H₂O的形式结晶析出。将所得结晶物热解,再将热解产物加水溶解,最后将溶解液浓缩结晶得到合格的NiSO₄·6H₂O产品。复盐结晶法是一种清洁环保、经济高效的从铜电解液中分离回收镍的方法。     

Preparation of copper arsenite and its application in purification of copper electrolyte

The preparation of copper arsenite with arsenic trioxide was presented and its application in the purification of copper electrolyte was proposed. The variables of n（OH^-）/n（As）, n（Cu）/n（As）, NaOH concentration, reaction temperature and pH value have some effects on the yield of copper arsenite. The optimum conditions of preparing copper arsenite are that the molar ratio of alkali to arsenic is 2：1, NaOH concentration is 1 mol/L, the molar ratio of copper to arsenic is 2：1, pH value is 6.0 and reaction temperature is 20℃. The yield of copper arsenite is as high as 98.65% under optimum conditions and the molar ratio of Cu to As in the product is about 5：4. The results of the purification experiments show that the removal rate of antimony and bismuth is 53.85% and 53.33% respectively after 20g/L copper arsenite is added. The purification of copper electrolyte with copper arsenite has the advantages of simple technique, good purification performance and low cost.     

Separation and recovery of Cu and As from copper electrolyte through electrowinning and SO2 reduction

Cu and As were separated and recovered from copper electrolyte by multiple stage electrowinning, reduction with SO₂ and evaporative crystallization. Experimental results showed that when the current density was 200 A/m², the electrolyte temperature was 55 °C, the electrolyte circulation rate was about 10 mL/min and the final Cu concentration was higher than 25.88 g/L, the pure copper cathode was recovered. By adjusting the current density to 100 A/m² and the electrolyte temperature to 65 °C, the removal rate of As was 18.25% when the Cu concentration decreased from 24.69 g/L to 0.42 g/L. After As(V) in Cu-depleted electrolyte was fully reduced to As(III) by SO₂, the resultant solution was subjected to evaporative crystallization, then As₂O₃ was produced, and the recovery rate of As was 59.76%. The cathodic polarization curves demonstrated that both Cu²⁺ concentration and As(V) affect the limiting current of Cu²⁺ deposition.     

Sb(V) removal from copper electrorefining electrolyte: Comparative study by different sorbents

Removal of Sb(V) from copper electrolyte by different sorbents such as activated carbon, bentonite, kaolin, resin, zeolite and white sand was investigated. Adsorption capacity of Sb(V) removal from copper electrolyte was as follows: white sand < anionic resin < zeolite < kaolin < activated carbon < bentonite. Bentonite was characterized using FTIR, XRF, XRD, SEM and BET methods. The results show specific surface area of 95 m²/g and particles size of 175 nm for bentonite. The optimum conditions for the maximum removal of Sb are contact time 10 min, 4 g bentonite and temperature of 40 °C. The adsorption of Sb(V) on bentonite is followed by pseudo-second-order kinetic (R²=0.996 and k=9×10^?5 g/(mg·min)). Thermodynamic results reveal that the adsorption of Sb(V) onto bentonite from copper electrolyte is endothermic and spontaneous process (ΔG^Θ=–4806 kJ/(mol·K). The adsorption data fit both the Freundlich and Langmuir isotherm models. Bentonite has the maximum adsorption capacity of 10000 mg/g for adsorption of Sb(V) in copper electrolyte. The adsorption of Zn, Co, Cu and Bi that present in the copper electrolyte is very low and insignificant.     

Novel technology of purification of copper electrolyte

The effects of arsenic with different valence states on the purification of copper electrolyte were studied and a novel technology of purification of copper electrolyte by copper arsenite was proposed. The results show that the purification performance of As（Ⅲ） compounds is better than that of As（Ⅴ） compounds. The purification technology by copper arsenite has the advantages of simple operation, high purification performance and low cost in comparison with other technologies and its appropriate purification conditions are that copper arsenite concentration is 18 g/L, reaction temperature is 65 ℃ and reaction time is 8 h. The removal rates of Sb and Bi are 53.22% and 58.67% respectively under these conditions. The purification principle show that a kind of yellow precipitate mainly composed of arsenic, antimony （ Ⅴ ）, bismuth and oxygen forms in electrolyte after copper arsenite is added, and consequently antimony and bismuth are removed from electrolyte.     

Purification mechanism of copper electrolyte by As（Ⅲ）

A new kind of precipitate, antimony arsantimonate, was found during the precipitation reactions in acidic solution containing As（Ⅲ）, Sb（Ⅲ） and Sb（ Ⅴ ） by means of chemical analysis, SEM, XRD and IR spectrometry. The results show that the As content in antimony arsantimonate increases with the increase of n（As（Ⅲ）/n（Sb） in solution and the content of component Sb（Ⅲ） and Sb（Ⅴ） remains almost constant with the variation of n（Sb（Ⅲ））/n（Sb（Ⅴ）） in solution. The antimony arsantimonate is a kind of floccules with size of 1-5 μm. The crystal performance of the compound gets better with the decrease of n（As（Ⅲ））/n（Sb）, the cell parameter of which is near to 10.33×10^-10m under different n（As（Ⅲ））/n（Sb） and As atom locates on the surface, not in the inner of the grain. The chemical bonds of As--OH, Sb---OH, As---O--Sb, Sb--O---Sb and O---H of the precipitate are included in the precipitate. The chemical structure of precipitate is described as Sb（OH）2---O--[Sb（OH）3--（O---As（OH）--O---Sb（OH）3）3]----O--- Sb（OH）2·xH2O. The structure analysis shows that the copper electrolyte can be purified by As（Ⅲ） because the antimony arsantimonate precipitate forms.     

含砷污酸资源化回收铜和砷的新工艺

以含砷污酸为原料,通过中和除杂-沉砷-洗涤-浸出-蒸发结晶-溶解制取三氧化二砷,实现含砷污酸的资源化。结果表明：将污酸中和至pH为2,使污酸的酸度降低;在中和液中加入硫酸铜,控制Cu和As的摩尔比为1.5：1,调节体系pH为8沉淀As,得到亚砷酸铜,As的沉淀率达到97.81%;通过洗涤除杂提高亚砷酸铜中As和Cu的含量;采用10%硫酸溶液,在液固比为5：1条件下浸出亚砷酸铜,所得溶液蒸发结晶得到三氧化二砷与硫酸铜的混合物;用水溶解该混合物后过滤得到硫酸铜溶液及符合 YS/T-99-1997As2O3-3号产品标准的三氧化二砷。     

铜火法冶炼过程中铜和砷物质流分析

采用物质流分析方法对铜火法冶炼过程铜和砷的代谢进行分析,建立铜和砷的物质平衡表及物质流图.采用直接回收率、废物循环率和资源效率等指标评价流程代谢效率.结果表明,该流程铜资源效率为97.58％,在熔炼、吹炼和精炼单元过程铜的直接回收率分别为91.96％、97.13％和99.47％.同时,生产1 t金属铜有10 kg砷进入...     

铜闪速熔炼渣中砷的赋存状态和浸出毒性（英文）

铜冶炼含砷炉渣的高效安全处置取决于对其含砷物相及其浸出毒性的准确认识。采用X射线荧光光谱、X射线衍射、电子探针显微分析、扫描电子显微术和选择性逐级提取法对铜熔炼渣中的含砷物相进行鉴定,并基于对炉渣中不同含砷物相的选择性逐级提取结果探讨渣中砷浸出毒性的可能来源。结果表明,砷以水溶性砷、铜砷金属间化合物、铜砷硫化物以及固化在铁橄榄石和硅酸盐玻璃相中的砷等形式赋存在熔炼渣中。浮选过程可以去除熔炼渣中的水溶性砷并回收铜砷金属间化合物,降低渣尾矿的砷浸出毒性,使其符合USEPA和SEPA标准要求。