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1.
铁离子和亚铁离子对滑石浮选的影响及作用机理   总被引:1,自引:0,他引:1  
通过对滑石纯矿物的浮选实验和动电位的测试,结合水解金属离子溶液化学计算,研究铁离子和亚铁离子对滑石浮选的影响,并探讨其吸附机理。实验结果表明:在没有金属氢氧化物沉淀时溶液中存在的水解金属离子在滑石表面的吸附对滑石的非极性表面和极性端面产生不同的影响,使滑石ξ电位的符号由负变正,但滑石的天然可浮性不变;在金属氢氧化物沉淀的pH值与它的零电点之间,滑石的非极性表面变得亲水,导致滑石的浮选受到抑制。其疏水性的改变是由于在氢氧化物沉淀的pH值与它的零电点之间,在滑石的极性和非极性表面产生了氢氧化物沉淀的多相凝聚。  相似文献   

2.
为高效率地脱除H2S液相氧化还原得到的硫磺,开发了气升式二级环流泡沫分离反应器。以含有硫磺的脱硫溶液为模拟体系,测量了气速、表面活性剂十二烷基苯磺酸钠(SDBS)质量流量、泡沫相高度和鼓泡相高度比、pH等对硫磺泡沫分离效果的影响。结果表明:低气速有利于泡沫分离;硫磺回收率随表面活性剂SDBS质量流量的增大先增大后基本不变,又随泡沫相和鼓泡相高度比下降而增大;在pH 8~10范围内,分离效果良好。优化条件下,硫磺回收率可达97.43%。  相似文献   

3.
The Sarcheshmeh copper flotation circuit is producing 5×104 t copper concentrate per month with an averaging grade of 28% Cu in rougher, cleaner and recleaner stages. In recent years, with the increase in the open pit depth, the content of aluminosilicate minerals increased in plant feed and subsequently in flotation concentrate. It can motivate some problems, such as unwanted consumption of reagents, decreasing of the copper concentrate grade, increasing of Al2O3 and SiO2 in the copper concentrate, and needing a higher temperature in the smelting process. The evaluation of the composite samples related to the most critical working period of the plant shows that quartz, illite, biotite, chlorite, orthoclase, albeit, muscovite, and kaolinite are the major Al2O3 and SiO2 beating minerals that accompany chalcopyrite, chalcocite, and covellite minerals in the plant feed. The severe alteration to clay minerals was a general rule in all thin sections that were prepared from the plant feed. Sieve analysis of the flotation concentrate shows that Al2O3 and SiO2 bearing minerals in the flotation concentrate can be decreased by promoting the size reduction from 53 to 38 μm. Interlocking of the Al2O3 and SiO2 bearing minerals with chalcopyrite and chalcocite is the occurrence mechanism of silicate and aluminosilicate minerals in the flotation concentrate. The dispersed form of interlocking is predominant.  相似文献   

4.
废水中氨氮沉淀物的结晶状态及其与捕收剂的作用机理   总被引:5,自引:0,他引:5  
用实验室模拟废水和焦化废水研究了废水中其他成分对氨氮沉淀物结晶状态的影响.X射线衍射结果表明,模拟废水中生成的氨氮沉淀物是非晶态的,而焦化废水中的沉淀物是晶态的磷酸铵镁.红外光谱测试结果表明,pH值影响捕收剂十二酸钠或油酸钠与沉淀物的作用机理,pH=9时捕收剂在沉淀物表面发生物理吸附,而pH=11时发生化学吸附.模拟废水中氨氮沉淀物以油酸钠为捕收剂较好,而焦化废水中的氨氮沉淀物以十二酸钠为较好,其原因是沉淀物的结晶状态不同.  相似文献   

5.
Pure mineral flotation experiments, zeta potential testing, and infrared spectroscopy were employed to investigate the interfacial reactions of oleic acid (collector), sodium dodecyl benzene sulfonate (SDBS, synergist), and rhodochrosite in an anionic system. The pure mineral test shows that oleic acid has a strong ability to collect products on rhodochrosite. Under neutral to moderately alkaline conditions, low temperature (e.g., 10℃) adversely affects the flotation performance of oleic acid; the addition of SDBS significantly improves the dispersion and solubility of oleic acid, enhancing its collecting ability and flotation recovery. The zeta potential test shows that rhodochrosite interacts with oleic acid and SDBS, resulting in a more negative zeta potential and the co-adsorption of the collector and synergist at the mineral surface. Infrared spectroscopy demonstrated that when oleic acid and SDBS are used as a mixed collector, oleates along with -COO- and -COOH functional groups are formed on the mineral surface, indicating chemical adsorption on rhodochrosite. The results demonstrate that oleic acid and SDBS co-adsorb chemically on the surface of rhodochrosite, thereby improving the flotation performance of the collector.  相似文献   

6.
The enrichment mechanisms of precious metals by base metals or their mattes in pyrometallurgical processes are discussed at the atomic level in this paper. The reasons brought forward for a trace amount of precious metals to be trapped into base metals or mattes are that the melted slag phases possess different chemical structures and properties from that of the melted base metal or matte phases. As for the melted slag phase, its formation is thought to depend on the covalent bonds and the ionic bonds between Si, O atoms and Ca2+, Mg2+, Fe2+ ions to tie up each other. Because the bridging electrons in the slag phase are all thought as the localized electrons, the precious metal atoms are not stable among them. However, as for the metal phase, its formation is thought depend on the metal bonds to bind up the metal atoms. Because the electrons in the metal phases can move freely among the atoms, the precious metal atoms that enter the metal phase can cause the system’s free energy to decrease. For the melted mattes phase,because it has high electrical conductivities (between 103~104 s·cm-1) at higher temperatures, and its temperature coefficients presents the negative values, its conductance mechanism belongs with the electronic conduction. The property of the mattes is in fact similar to that of the metal at their melted state, so the precious metal atoms will enter the matte phase instead of the slag phase in a mattesmelting process.  相似文献   

7.
土壤重金属污染治理与修复方法研究进展   总被引:5,自引:0,他引:5  
土壤重金属污染的治理和修复的基本原理是将重金属清除或改变其在土壤中的存在形态,降低迁移性和生物可利用性。根据土壤的性质和重金属在土壤中的赋存形态不同,目前重金属污染土壤治理和修复方法可分为工程物理化学法、土壤农化调控法和生物学修复法。通过对重金属污染治理与修复方法的综述,得出了各种方法的优缺点和适用范围,并对重金属治理的方法进行了展望。  相似文献   

8.
铜阳极泥全湿法处理过程中贵贱金属的行为   总被引:1,自引:0,他引:1  
针对某铜冶炼企业在铜阳极泥回收处理过程中出现的效率低、污染大等问题,提出了一种全湿法处理铜阳极泥的工艺,并且采用物质流方法对其工艺过程中的铅、铜、银、金、铂、钯等贵贱金属的行为进行研究.结果表明:在全湿法处理阳极泥工艺中,铅、铜、银、金的分布比较集中,铅、铜对处理工艺影响较小;99%左右的金富集到粗金粉中;粗银粉富集了阳极泥中近99%的银;铂和钯的直收率较低,分布较分散,大部分金属铂和钯存在于铂钯精矿、析铂钯后液和分铅渣中.  相似文献   

9.
非晶新型代银钎料的制备及性能研究   总被引:7,自引:2,他引:7  
采用液态单辊急冷法,在大气下制备了几种非晶态新型代银钎料箔带,其材料的最佳成分数w(Cu)为68%~79%,w(Ni)为5%~14%,w(Sn)为4%~10%,w(P)为7%.在反复实验的基础上,确定了合理的钎料母合金熔炼工艺和单辊急冷法制备工艺,冷辊转速、喷嘴口尺寸、喷带的间隙和喷射压力是制备非晶态箔带的关键工艺参数.制得的几种非晶态新型代银钎料箔带成型性良好,对折180°不折断.并利用DTA,SEM及XRD等方法对Cu P非晶态钎料箔带的非晶形成能力及熔化特性进行了研究.结果表明,制备的Cu Ni Sn P非晶合金箔带熔点和润湿性与Ag基钎料接近.  相似文献   

10.
Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imidazolium hydrogen sulfate ([bmim]HSO4) at ambient pressure in the presence of hydrogen peroxide (H2O2) and potassium peroxymonosulfate (oxone) as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO4 is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99% for Zn and 24.82% for Cu at a concentration of 50vol% [bmim]HSO4 in the aqueous solution without any oxidant. However, more than 99% of zinc and 82% of copper are leached by the addition of 50vol% H2O2 to the [bmim]HSO4 solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO4.  相似文献   

11.
为了适应社会主义市场经济的需要,以培养应用性专门人才为目标的高职院校,应该选择适当的教育模式。我院率先在汽车运用技术专业开展了CBE/DACUM教育模式教改试点工作。  相似文献   

12.
吴旭  陶涛  吴润泽  王晓琳 《科学技术与工程》2021,21(27):11768-11775
探讨用水结构对实现区域水资源合理优化配置及经济协调发展具有重要意义。根据2008—2017年邯郸市用水数据,运用信息熵原理、洛伦兹曲线和基尼系数等方法分析了该区域用水结构的时间演变和空间分布差异性,并采用重心模型从经济发展的角度对其空间演变特征进行了验证。结果表明:2008—2017年,邯郸市用水总量总体呈波动下降趋势,用水结构均衡性和稳定性整体增强。空间动态分布上,用水结构演变呈现较显著的区域性差异,农业用水重心、工业用水重心、生活用水重心分别主要分布在邯郸市东部、中西部、中部地区。在区域异质性基础上,邯郸市需因区施策,合理调整优化产业结构,促进要素集聚,实现区域经济与水资源空间分布协调发展。  相似文献   

13.
研究了使用纯水射流进行路面清洗时,影响路面清洗率的清洗参数.采用模糊数学方法建立了清洗率预测的数学模型,通过实验建立了用于预测清洗率的模糊规则库.通过规则推理,实现了在给定输入参数条件下,对清洗率的准确预测.经实验验证,预测误差小于5%.  相似文献   

14.
微重力下对流换热的地面缩比-减压模拟技术   总被引:10,自引:0,他引:10  
为了地面模拟空间飞行器在微重力条件下的对流换热 ,抑制自然对流 ,消除或减小重力的影响 ,研究了将缩小尺寸和减小压力相结合的缩比 -减压模拟技术 ,并通过数值计算对这一技术进行了验证。研究表明 ,缩比 -减压法可以克服缩比法和减压法在应用时的不足。不论缩小尺寸和减小压力的程度如何 ,只要缩减比相等 ,自然对流的抑制效果就相同。在工程应用中 ,对一定的原型工况 ,采用缩减比参数比采用 Gr/Re2 参数更直观 ,可以指导对地面模拟实验中合适的模型尺寸和工作压力的确定  相似文献   

15.
采用电感耦合等离子体质谱法(ICP-MS)对西宁市典型文化用地——青海师范大学南校区的表层与剖面土壤样品中As、Cd、Cr、Pb、Mn、Cu、Zn等7种重金属元素进行了分析,评估了其污染程度并分析其来源.结果表明,表层土壤中Cd(0.37~0.87mg/kg,平均0.57mg/kg)的含量高于青海省土壤背景值数倍,As(11.8~14.8mg/kg,平均13.2mg/kg)、Cr(69~119mg/kg,平均86mg/kg)、Pb(30.1~48.3mg/kg,平均35.7mg/kg)、Mn(628~730mg/kg,平均698mg/kg)、Cu(25.8~31.1mg/kg,平均28.9mg/kg)、Zn(110~166mg/kg,平均128mg/kg)的含量略高于或接近青海省土壤背景值;富集系数法、地累积指数法和潜在生态危害指数法一致指示Cd达到中度污染水平,Cr、Pb、Mn、Cu、Zn为轻度污染水平,该地重金属污染达到中等至较高生态风险级别.相关分析、聚类分析和剖面对比分析共同显示青海师范大学南校区的重金属污染来自人类活动,交通排放和大气降尘是其主要来源.  相似文献   

16.
集装箱底板用胶合板中铬、砷含量的检测   总被引:1,自引:0,他引:1  
根据木材绝干质量恒定的原理,通过优化集装箱底板用胶合板的制备过程和目标物质添加方式,制备出含有一定浓度铬、砷元素的集装箱底板用胶合板.对制得的阳性样品进行处理,利用原子吸收分光光度计测定铬,原子荧光分光光度计测定砷,检测结果表明制备的阳性样品中目标物质的均匀性和抗流失性良好.该检测方法快速、简便,其精密度、准确度以及所用仪器的灵敏度均能满足日常检测工作的需要.  相似文献   

17.
给出了A2型量子代数Vcrma模Y(z)的两组典范基,在基上直接计算出了Y(z)的所有极大向量.  相似文献   

18.
催化剂分子设计专家系统中数据库和知识库的建立   总被引:3,自引:1,他引:3  
从建造专家系统的理论体系出发,结合作者以前在计算机辅助催化剂分子设计方面所做的工作,确立了复合催化剂组分子设计专家系统的基本结构,并探讨了这一系统的任务功能、体系结构与支持界面、性质数据库与知识规则库的建立.以甲烷氧化偶联反应为例,说明了数据库的构成和领域知识的分类以及相应的知识表示技术.  相似文献   

19.
Optical reflection and transmission spectra of Se_(80-x)Te_(20)Ag_x(where x=0,5,10 and 15,molar percent) chalcogenide thin films have been obtained in the range 300-1 200 nm at room temperature.Glassy samples are prepared by melt quenching technique and thin films are obtained by using vacuum evaporation technique on glass transition at room temperature.The present paper reports the effect of Ag contents on various optical parameters such as optical band gap,refractive index,extinction coefficient,absorp...  相似文献   

20.
基于创业教育的高校创新基地的构建与实施   总被引:1,自引:0,他引:1  
创新基地的建设是高等学校本科教学质量与教学改革工程的重要环节。本文以创业教育实践为出发点.分析了创新基地的目标取向和创新基地的构建条件。阐述了创新基地的管理机制和基于“项目”的创业教育运行模式。针对创业教育的系统性,从培养学生创业素质和创业技能角度,说明了创新基地构建过程中需要进一步完善的问题。  相似文献   

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