The selective leaching of uranium,vanadium and phosphorus from phosphate ore with hydrochloric acid

The selective leaching of uranium, vanadium, and phosphorus from phosphate ore may be useful in by-product recovery. Experimental results have shown that it is possible to preferentially remove uranium from phosphate ore using dilute HCl (0.05 M). 93 pct of the uranium is leached within 90 min, leaving 94 pct of the phosphorus and 82 pct of the vanadium unattacked. Phosphorus may then be removed by increasing the pH. The apparent activation energies and orders for the leaching reactions were found. For uranium, the apparent order with respect to H⁺ is 1.05 and the apparent activation energy is 7750 J. The apparent order for the leaching of the vanadium minerals with respect to H⁺ is 1.93 and the apparent activation energy is 12800 J. The phosphorus reaction has an apparent order, with respect to H⁺, of 1.98 and an apparent activation energy of 10200 J. The uranium readsorbs at longer times. The readsorption reaction is a function of temperature, particle size, and H⁺ concentration. Two methods of selectivity analysis were used in the analysis of the data-end point analysis and initial rate analysis.     

细菌氧化—硫脲浸金试验研究

对细菌氧化后矿浆进行了硫脲提金试验研究,研究结果表明,细菌氧化后采用硫脲浸金—树脂吸附提金,可以获得９３ ．８１ ％ 的选矿回收率,具有深入研究和推广应用价值。     

Sulfuric acid leaching of polymetallic Abu Zeneima gibbsite-shale

The gibbsite shales belonging to the Paleozoic sequence of sedimentary rocks occurring at the Abu Zeneima area in SW Sinai Egypt has been found to host several economic metal values. These include Al, Cu, Zn, Co, Ni, REE, and U beside several Mn minerals. In this work, the ore was subjected to sulfuric acid leaching to maximize extraction of these metal values. The optimum leaching conditions were 800 g/L acid with a Solid/Liquid ratio of 1/2 at 100 °C for 4 h and using an ore size of − 60 mesh. Under these conditions, it was possible to achieve high leaching efficiencies with complete leaching of Al together with 93.0% Cu, 58.6% Zn, 69.0% Co, 92.6% Ni and 84.4% U. Extension of the leaching time to 8 and 12 h significantly improved the leaching efficiencies of Co and Zn to 91.0% and 84.0% respectively.     

阳山金矿矿石的氰化浸出工艺试验研究

阳山金矿矿石属于卡林型金矿石,经过增浸剂预处理,在加活化剂条件下,金的氰化浸出率从10％～30％提高到80％～90％,浸出速度也有较大提高。     

云南某难处理硫化银矿石氰化浸出试验研究

对云南某难处理硫化银矿石进行氰化浸出及锌粉置换工艺试验研究。通过对其影响因素进行探讨,得出最佳试验条件,且可获得68.41%的银浸出率,高于理论浸出率;将锌粉用质量分数1%的硝酸铅溶液浸泡10 min后,过滤清洗,再进行贵液置换,银的置换率达86.79%,指标相对较好,而锌粉的处理方式是影响贵液置换的关键因素。     

硫脲浸取某含金矿石的试验研究

对经过焙烧，且钴、铜、镍、钼、铋等有用元素基本已浸出的某含金多金属矿石浸渣，进行了硫脲浸金试验。试验结果表明。当硫脲用量为8kg／t，浓硫酸用量20L／t，浸出时间为4h，金的浸出率达90％以上。     

从钴铜矿浸出液中萃取-电积铜

介绍了用萃取-电积脱铜技术替代铁屑置换或碳酸钠中和沉淀,从氧化钴铜矿浸出液中脱除铜的生产实践及主要技术经济指标。     

从钴铜矿浸出液中萃取-电积铜

介绍了用萃取-电积脱铜技术替代铁屑置换或碳酸钠中和沉淀,从氧化钴铜矿浸出液中脱除铜的生产实践及主要技术经济指标。     

A kinetic study on the pressure leaching of sphalerite

The dissolution of sphalerite (ZnS) in sulfuric acid solution under oxygen pressure was investigated. Effects of temperature, percent solids, agitation, sample size, oxygen partial pressure and foreign ions were evaluated. The effect of hydrogen pretreatment on sphalerite leaching rate was also examined. Leaching of sphalerite at 90°C and 150 psi oxygen pressure was found to occur at a constant rate. This rate was determined from the experimental data observed under the different leaching conditions mentioned above. The constant leaching rate was attributed to the chemical reaction occurring on the surface of the flat-plate type sphalerite sample. The rate-controlling step of the reaction was determined to be the oxidation of hydrogen sulfide to elemental sulfur. Oxidation of hydrogen sulfide was studied through the addition of iron and through the observation of the change in iron concentration during leaching. The oxidation was concluded to be by reaction with ferric ion rather than by direct oxygen oxidation. Leaching tests run with samples pretreated with hydrogen do not show any increase in the rate of zinc extraction. M. T. HEPWORTH, formerly with University of Denver.     

低品位金矿浸出新工艺研究

本文研究了低品位金矿石的浸出方法。将矿石在700℃焙烧后,掺混一种添加剂,在盐酸溶液中进行搅拌浸出或渗滤浸出,其金的浸出率均大于90％。     

磷酸钠-氢氧化钠浸出氟化钙动力学研究

针对现行主流氢氧化钠和碳酸钠浸出低品位白钨矿存在浸出剂用量大,浸出率低的弊端,提出磷酸钠-氢氧化钠-氟化钙协同高效浸出低品位白钨矿的新工艺.氟化钙作为固体氟源,在浸出过程中首先发生溶解并释放出游离的氟离子,再参与白钨矿的浸出反应生成氟磷酸钙沉淀.因此,氟化钙的溶解速率对白钨矿浸出速率有较大影响.文章使用等浸出率法,对磷...     

An evaluation of the leaching characteristics of butte leaching ore

The results of leaching experiments in columns simulating 80 and 200 ft deep cores through a leach dump are discussed. By equipping the columns with can precipitation plants, actual plant conditions could be duplicated.The results indicated that the copper grade increased with depth as long as the pH and the availability of oxygen were not limiting. In the sealed 200 ft system lack of oxygen restricted biological activity; activity increased when air was introduced. However the free diffusion of oxygen was restricted by clay formation and fines accumulation at specific levels within the column.Copper grades as high as 2.6 g/l were obtained initially but grade declined steadily as extraction progressed. The decline was most rapid after the extraction had reached 50%. In agreement with field observations, the recirculation of pregnant liquor did not increase the pregnant grade. The reason for this is discussed. The results, which produced a better understanding of physical and chemical limitations of the leaching process, are discussed in the light of commercial practice.     

高碱复杂氧化铜矿石酸浸动力学研究

为了研究某高山矿区高碱复杂氧化铜矿石硫酸浸出过程动力学,试验采用电子显微镜扫描、电子探针分析研究了矿石的化学特征;对浸出温度、矿石粒度、液固比和初始酸度等因素进行了多水平的搅拌浸出试验。结果表明,选取的各因素能显著影响矿石的浸出率和浸出速率。采用未反应的缩小核模型进行浸出动力学分析,从动力学模型、表观活化能和颗粒表层产物3方面确定表面化学反应为浸出过程的控制步骤,得出矿石表观活化能和宏观浸出速率方程,并解释了反应后期浸出体系的化学动态平衡。     

矿石的制粒堆浸

本文阐述了堆浸制粒新技术的发展历史和对开发利用低品位矿产资源的重大意义,列举了湖南某金旷粉矿制粒堆浸新工艺半工业试验研究,文中研究方法和所得结果对于类似矿山皆有推广实用价值。     

难选金矿石的细菌浸出

对金呈细粒浸染状嵌布的含砷、含铜难选金矿石进行了细菌脱砷、脱硫、脱铜的试验研究。生物浸渣由氰化或硫脲浸出，金的浸出率达８７％以上。研究了影响细菌生长、浸出的各种有关因素及由此引起的金属溶解现象，为细菌浸出在工业上应用提供了技术参考。     

A kinetic study of the leaching of chalcopyrite at elevated temperatures

A study of the rate of dissolution of chalcopyrite (CuFeS₂) in acidic solutions under oxygen overpressures was carried out by measuring the rate of formation of cupric ions in solution. Effects of temperature, oxygen partial pressure, surface area, and concentration of sulfuric acid were evaluated. A sized batch of chalcopyrite was leached in the temperature range of 125 to 175° and in the pressure range of 75 to 400 psi of oxygen. In 0.5N H₂SO₄ all products of reaction went into solution except for trace amounts of elemental sulfur. The dissolution of chalcopyrite followed linear kinetics and was essentially independent of hydrogen ion concentration for H₂SO₄ concentrations between 0.2 and 0.5 JV. The oxygen dependence indicated adsorption approaching limiting values with increasing oxygen pressure. The linear mechanism was explained in terms of steady-state adsorption of oxygen at the chalcopyrite surface followed by a surface reaction. The enthalpy of activation for adsorption of oxygen was found to be approximately 33 kcal per mole. An activation enthalpy of approximately 9 kcal per mole was observed for the surface reaction. Charge transfer reaction are not rate controlling in the process.     

Reduction leaching of rare earth from ion-adsorption type rare earths ore with ferrous sulfate

The practice of in-situ leaching of the ion-adsorption type rare earths ore with ammonium sulfate could only leach most of rare earth in ion-exchangeable phase,but not the colloidal sediment phase.Therefore,the reduction leaching of rare earth from the ion-adsorption type rare earths ore with ferrous sulfate was innovatively put forward.The soak leaching process and the column leaching process were investigated in the present study.It was determined that ion-exchangeable phase could be released,and part of colloidal sediment phase rare earth could be reduction leached by the cations with reduction properties.The mechanism of reduction leaching was discussed with the Eh-pH diagram of cerium.Moreover,the stronger reduction of reductive ions,the greater acidity of leaching agent solution,and the higher reductive ion concentration,could result in the higher rare earth efficiency and the bigger cerium partition in the leaching liquor.In the ferrous sulfate column leaching process,the rare earth leaching rate and the rare earth efficiency were a little higher than with(NH_4)_2SO_4 agent,and the rare earth efficiency and the partitioning of cerium in leaching liquor could be about 102% and 5.31%,respectively.However,the ferrous sulfate leaching process revealed some problems,so compound leaching with magnesium sulfate and a small amount of ferrous sulfate was proposed to an excellent alternative leaching agent for further studies,which may realize efficiency extraction and be environment-friendly.     

某金铜氧化矿石堆浸浸铜—氰化浸金试验研究

某金铜氧化矿石铜品位0.88%,金品位1.76 g/t,矿石氧化率为87.50%。金矿物主要为自然金、银金矿,铜矿物以氧化铜矿物为主。针对矿石性质,进行了堆浸浸铜、氰化浸金试验研究,考察了堆浸粒度、硫酸用量等堆浸条件及磨矿细度、氢氧化钠用量等氰化浸金条件对回收指标的影响。结果表明:在最佳条件下,采用硫酸法堆浸浸铜—氰化浸金工艺,铜浸出率为81.79%,金浸出率为95.00%。     

石煤氧化矿酸浸提钒研究

以湖南某地的石煤氧化矿为原料,探索研究了从石煤氧化矿中直接提钒,成分、XRD、差重等分析显示,该矿风化程度较高。实验结果表明:采用硫酸+助浸剂R_1+氧化剂R_2体系浸出该矿,一定条件下浸出率可达94%,且钒与石煤原矿一样主要赋存于硅酸盐晶格中。