Long-term corrosion of copper in a dilute anaerobic sulfide solution

The mechanism of corrosion of oxygen-free copper has been studied in stagnant aqueous sulfide solutions using corrosion potential and electrochemical impedance spectroscopy (EIS) measurements. Film structure and composition were examined on surfaces and on cross-sections prepared by focused ion beam (FIB) milling using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Experiments were conducted in anaerobic 5 × 10⁻⁵ mol dm⁻³ Na₂S + 0.1 mol dm⁻³ NaCl solutions for exposure periods up to 4000 h (∼167 days) to mimic (at least partially) the conditions that could develop on a copper nuclear fuel waste container in a deep geologic repository. The corrosion film formed was a single cellular Cu₂S layer with a non-uniform thickness. The film thickness increased approximately linearly with immersion time, which implied that the sulfide film formed on the Cu surface is non-protective under these conditions up to this exposure time. The film growth process was controlled by HS⁻ diffusion partially in the aqueous solution in the pores in the cellular sulfide film and partially in the bulk of the aqueous solution.     

硫化氢对氢化丁腈橡胶性能的影响

就硫化氢与丁腈橡胶和氢化丁腈橡胶的不饱和双键,以及与丙烯腈侧基的老化反应的机理作了介绍。研究表明:氢化丁腈橡胶具有优异的耐硫化氢性能,适合用来生产石油钻探领域的相关橡胶制品。     

Electrochemical sulfide removal and recovery from paper mill anaerobic treatment effluent

Sulfide can be removed from wastewater and recovered as elemental sulfur using an electrochemical process. Recently, we demonstrated this principle of product recovery on synthetic feeds. Here, we present a lab scale electrochemical reactor continuously removing sulfide from the effluent of an anaerobic treatment process operated on paper mill wastewater. The effluent contained 44 ± 7 mg of sulfide-S L⁻¹. Sulfide was reduced to 8 ± 2 mg-S L⁻¹, at a removal rate of 0.845 ± 0.133 kg-S m⁻³ of total anodic compartment (TAC) d⁻¹. The removed sulfide was recovered (75 ± 4% recovery) as pure concentrated alkaline sulfide/polysulfide solution, from which solid elemental sulfur was obtained. The electrochemical sulfide removal was not affected by different soluble constituents or particulate materials present in the wastewater. However, over time sulfide removal decreased due to biological sulfur reduction using the organics present in the wastewater. Therefore, a periodic switching strategy between anode and cathode was developed. Biofilm formation was avoided as the pH of the cathode solution increased to inhibitory levels during cathodic operation, while still allowing full recovery of the sulfur as end product.     

新疆某铜矿的浮选实验

这是一篇矿物加工工程领域的论文。新疆某铜矿石中矿物组成复杂、属于复杂难选氧化铜矿。矿石中硫化铜占总铜的35.67%,游离氧化铜和结合氧化铜占总铜的64.33%。脉石矿物种类多且与目标矿物之间嵌布关系复杂。采用先浮硫化铜矿物,再浮氧化铜矿物的原则流程进行了选矿工艺技术条件研究。针对该矿石性质,开展浮选条件实验,获得较佳工艺参数,磨矿细度-0.074 mm 65%,石灰用量为2500 g/t、捕收剂Z-200用量为100 g/t、硫化钠用量为1750 g/t、硫酸铵用量为550 g/t、戊基钠黄药用量为160 g/t。在较佳磨矿细度和药剂用量下,开展闭路浮选实验,闭路流程可以获得硫化铜精矿和氧化铜精矿两种产品,其混合铜精矿中Cu的品位为25.59%,Ag的品位为507.27 g/t,铜回收率为73.07%,银总回收率为70.27%。本研究为该氧化铜矿资源的高效利用提供了技术支撑。     

The influence of chlorine on the crystal structure and electroluminescent behavior of ZnS:Mn Films in thin film electroluminescent devices

Comparative experiments showed that the addition of chlorine at the preparation of the ZnS:Mn source materials for TFEL device fabrication can enhance grain growth in the ZnS:Mn films during post-deposition anneal. Correspondingly the luminescent properties of these films improved as compared to those without chlorine. Depending upon the Mn concen-tration and annealing temperature, both the saturation brightness and the peak luminous efficiency have increased by up to a factor of three. Optimized experimental para-meters resulted 810fL saturation brightness and 0.6l/W peak luminous efficiency. A practical significance is that useful TFEL devices can be fabricated using source materials with Cl, addition when post deposition annealing temperatures have to be kept low.     

含硫气体对燃气发动机的危害及脱硫方法

最近十年来,燃气发电机组在煤矿瓦斯、焦化尾气和沼气等领域的应用十分广泛。随着国民经济的发展,在国家环保政策的引导下,越来越多的可燃气体将应用到气体发动机中。而有些可燃气体中含有硫成份对发动机造成了一定的危害,本文简要介绍了舍硫气体对燃气发动机的危害及脱硫办法。     

Photocatalytic H2 evolution from NaCl saltwater over ZnS1−x−0.5yOx(OH)y-ZnO under visible light irradiation

Photocatalytic hydrogen production was investigated over ZnS_1−x−0.5yO_x(OH)_y-ZnO using sulfide ion (Na₂S-Na₂SO₃) as an electron donor from NaCl saltwater. NaCl can affect markedly the activity for photocatalytic hydrogen production, depending on NaCl concentration. When NaCl concentration is lower, the activity is lower than that in pure water, whereas when NaCl concentration is higher, the activity is higher than that in pure water. NaCl decreases not only the surface charge of ZnS_1−x−0.5yO_x(OH)_y-ZnO but also the surface hydration. When ZnS_1−x−0.5yO_x(OH)_y-ZnO was impregnated with the electron donor (Na₂S-Na₂SO₃), ZnO was transformed partly into ZnS. The impregnated ZnS_1−x−0.5yO_x(OH)_y-ZnO exhibits higher activity than the non-impregnated one. The possible mechanisms were discussed.     

啤酒中硫化物分析的进展

成品啤酒中含有微量含硫化合物,包括非挥发性和挥发性的硫化合物。当啤酒受到光照或氧化时,硫化物不仅使啤酒的口味变坏,而且会使啤酒发生雾浊,因此在啤酒的微量组成分中硫化物占有重要的地位。本文对啤酒硫化物分析中的常规分析法、色谱法和专用分析方法进行了综述。     

硫化矿石自燃倾向性鉴定技术

以BP神经网络为基础,建立了硫化矿石自燃倾向性鉴定模型,模型选用硫化矿石的吸氧量、自热起始温度和比表面积为输入层单元,自燃倾向性等级为输出层单元。运用MATLAB软件对模型进行了实现,将模型应用到硫化矿石自燃倾向性的实际鉴定中,预测结果真实可靠。