scholarly journals Recovery of Lithium from Lepidolite by Sulfuric Acid and Separation of Al/Li by Nanofiltration

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 981
Author(s):  
Lin Gao ◽  
Huaiyou Wang ◽  
Jinli Li ◽  
Min Wang
Keyword(s):  
Sulfuric Acid ◽  
Chemical Reaction ◽  
Hybrid Control ◽  
Sulfuric Acid Concentration ◽  
Product Layer ◽  
Single Step ◽  
Acid Extraction ◽  
Agitation Rate ◽  
Leaching Solution ◽  
Sulfuric Acid Method

The recovery and leaching kinetics of lithium from lepidolite by sulfuric acid method were investigated in this study, and a new method of nanofiltration to separate Al/Li from lepidolite leaching solution was coupled. The results indicated the optimal conditions about leaching lithium from lepidolite: leaching at 433 K for 4 h with the agitation rate of 120 r min−1, sulfuric acid concentration of 60 wt%, liquid-solid mass ratio of 2.5:1, under which the Li yield could reach at 97%. The kinetics observations revealed that the leaching process was controlled by the hybrid control of solid product layer diffusion and the chemical reaction, and dominated by chemical reaction step, which improved the conclusion of single-step control in the previous literature. A successful attempt was made to couple nanofiltration separation with sulfuric acid extraction of lithium, and DK membrane was used to separate Al/Li from lepidolite leaching solution. DK membrane has shown excellent retention of Al3+ and Ca2+ and also can effectively permeate Li+, which may bring a new inspiration for lithium extraction from lepidolite in the future.

scholarly journals Leaching Behaviors of Impurities in Titanium-Bearing Electric Furnace Slag in Sulfuric Acid

Processes ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 56
Author(s):  
Wenlin Nie ◽  
Shuming Wen ◽  
Dan Liu ◽  
Qian Zhang ◽  
Junbo Liu ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Electric Furnace ◽  
Early Stage ◽  
Sulfuric Acid Concentration ◽  
Weight Ratio ◽  
Impurity Content ◽  
Product Layer ◽  
Leaching Rate ◽  
Electron Microscopy Analysis ◽  
Furnace Slag

Titanium-bearing electric furnace slag (TEFS) was prepared from vanadium titanomagnetite and leached with sulfuric acid. The Ti leaching rate of vanadium titanomagnetite TEFS is significantly lower than that of ilmenite TEFS. The impurity content in vanadium titanomagnetite TEFS is higher than that in ilmenite TEFS. This might be one of the main factors resulting in the low leaching rate of Ti, so the leaching behaviors of various impurities under different conditions (temperature, acid/solid weight ratio, particle size, and initial sulfuric acid concentration) were investigated. The following trends were observed under different leaching conditions: The leaching rate of Fe increased rapidly and reached equilibrium quickly, that of Si increased quickly in the early stage and then decreased in the later stage, that of Ca increased initially and reached equilibrium later, and the leaching rates of Mg and Al increased gradually until the equilibrium was reached. The leaching rate of Fe was too rapid to be able to investigate its leaching kinetics, and the insoluble leached products of Si and Ca interfered with their leaching. The effects of leaching parameters on the leaching of impurities were further analyzed by X-ray diffraction (XRD) and scanning electron microscopy analysis. XRD data indicated that spinel is the major Mg- and Al-bearing mineral in TEFS. Mg and Al showed similar leaching behaviors, and their leaching conformed to a new model based on interface transfer and diffusion across the product layer, both of which affect the leaching rate.

Kinetic Study on Sulfuric Acid Dissolution of NaxH2-xTiO3 from Sodium Hydroxide Molten Method

2014 ◽  
Vol 881-883 ◽  
pp. 1545-1548 ◽  
Author(s):  
Wei Jing Wang ◽  
Tian Yan Xue ◽  
Dong Wang ◽  
Tao Qi
Keyword(s):  
Experimental Data ◽  
Sulfuric Acid ◽  
Sulfuric Acid Concentration ◽  
Product Layer ◽  
Dissolution Kinetic ◽  
Shrinking Core Model ◽  
Acid Dissolution ◽  
Titanium Slag ◽  
Slag Treatment ◽  
Shrinking Core

The dissolution kinetic of NaxH2-xTiO3(resulting from high titanium slag treatment by NaOH) by diluted sulfuric acid (38~51 wt. %) was carried out in temperature range of 10 to 50°C with an initial acid/NaxH2-xTiO3(wt.) ratio of 1:1. The effects of the sulfuric acid concentration and temperature on titanium dissolution percent were reported, and both of them significantly affected the dissolution rate. The experimental data indicate that the shrinking core model controlled by diffusion in product layer is most applicable for the titanium dissolution process, and the apparent activation energy has been estimated to be 28.69 kJ/mol.

Kinetics of Sulfuric Acid Leaching of Boron Slurry

2011 ◽  
Vol 366 ◽  
pp. 370-373
Author(s):  
Feng Gao ◽  
Xiang Guang Xu ◽  
Lei Li ◽  
Huai Yu Sun ◽  
Hong Xin Wang
Keyword(s):  
Particle Size ◽  
Sulfuric Acid ◽  
Acid Concentration ◽  
Reaction Temperature ◽  
Sulfuric Acid Concentration ◽  
Acid Leaching ◽  
Product Layer ◽  
Leaching Kinetics ◽  
Diffusion Controlled ◽  
Reaction Activation Energy

The results of a leaching kinetics study of boron slurry with sulfuric acid were presented. Effect of ore particle size, reaction temperature, and acid concentration on magnesium dissolution rate were determined. The results shown that leaching of about 64.61% of magnesium was achieved using (-200+ 250) mesh ore particle size at a reaction temperature of 60°C for reaction time 100 min with 25% sulfuric acid concentration. Leaching kinetics indicated that diffusion through the product layer was the rate controlling process during the reaction. The reaction activation energy was determined to be about 3.35 kcal/mol, which was characteristic for a diffusion– controlled process.

scholarly journals Recovery of Zinc and Copper from Mine Tailings by Acid Leaching Solutions Combined with Carbon-Based Materials

2021 ◽  
Vol 11 (11) ◽  
pp. 5166
Author(s):  
María Luisa Álvarez ◽  
Ana Méndez ◽  
Roberto Rodríguez-Pacheco ◽  
Jorge Paz-Ferreiro ◽  
Gabriel Gascó
Keyword(s):  
Sulfuric Acid ◽  
Mine Tailings ◽  
Sulfuric Acid Concentration ◽  
Acid Leaching ◽  
Future Research ◽  
Low Grade ◽  
Leaching Solution ◽  
Leaching Experiments ◽  
Sulfuric Acid Solutions ◽  
Carbon Based

Mine tailing storage represents an important environmental issue. The generation and dispersal of dust from mine tailings can contaminate air and surrounding soils. In addition, metals and soluble salts present in these wastes could pollute groundwater and surface water. The recovery of metals from mine tailings can contribute to minimize the environmental risk and to achieve a circular economy model. The main objective of the present work is to study the use of two carbon-based materials, a commercial activated carbon (AC) and a commercial charcoal (VC) in the leaching of zinc and copper from low-grade tailing waste. Experimental results obtained show that it is possible to achieve the recovery of more than 87 wt% of Zn after 6 h of leaching with different sulfuric acid solutions. The addition of carbon-based materials increases the extraction of Zn at high sulfuric acid concentrations (1 M) from 89% to 99%. The addition of VC significantly increases the extraction of Cu in leaching solution with high sulfuric acid concentration (1 M), from 41 to 61%. Future research will be necessary to optimize the properties of carbon-based materials and their recovery after leaching experiments in order to assess their potential for industrial application.

scholarly journals Effective Recovery Process of Copper from Waste Printed Circuit Boards Utilizing Recycling of Leachate

JOM ◽  
2020 ◽  
Author(s):  
Joona Rajahalme ◽  
Siiri Perämäki ◽  
Roshan Budhathoki ◽  
Ari Väisänen
Keyword(s):  
Hydrogen Peroxide ◽  
Sulfuric Acid ◽  
Printed Circuit Boards ◽  
Sulfuric Acid Concentration ◽  
Recovery Process ◽  
Copper Recovery ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Waste Printed Circuit Boards ◽  
Acid Consumption

AbstractThis study presents an optimized leaching and electrowinning process for the recovery of copper from waste printed circuit boards including studies of chemical consumption and recirculation of leachate. Optimization of leaching was performed using response surface methodology in diluted sulfuric acid and hydrogen peroxide media. Optimum leaching conditions for copper were found by using 3.6 mol L−1 sulfuric acid, 6 vol.% hydrogen peroxide, pulp density of 75 g L−1 with 186 min leaching time at 20°C resulting in complete leaching of copper followed by over 92% recovery and purity of 99.9% in the electrowinning. Study of chemical consumption showed total decomposition of hydrogen peroxide during leaching, while changes in sulfuric acid concentration were minor. During recirculation of the leachate with up to 5 cycles, copper recovery and product purity remained at high levels while acid consumption was reduced by 60%.

Separation and recovery of sulfuric acid from acidic vanadium leaching solution by diffusion dialysis

2012 ◽  
Vol 96 ◽  
pp. 44-49 ◽  
Author(s):  
Wang Li ◽  
Yimin Zhang ◽  
Jing Huang ◽  
Xiaobo Zhu ◽  
Yi Wang
Keyword(s):  
Sulfuric Acid ◽  
Leaching Solution ◽  
Diffusion Dialysis

Removal of Fe(III) from sulfuric acid leaching solution of phosphate ores with bisphosphonic acids

2021 ◽  
pp. 105799
Author(s):  
Chengjin Xu ◽  
Ling Li ◽  
Miaomiao Zhang ◽  
Xiao Meng ◽  
Xiujing Peng ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Acid Leaching ◽  
Sulfuric Acid Leaching ◽  
Leaching Solution ◽  
Bisphosphonic Acids ◽  
Phosphate Ores

Zinc carbonate recovery from brass melting slag

2021 ◽  
Vol 98 ◽  
pp. 14-18
Author(s):  
Thao Nguyen Thi ◽  
◽  
Nam Pham Ky ◽  
Ngoc Tran Vu Diem
Keyword(s):  
Sulfuric Acid ◽  
High Purity ◽  
Room Temperature ◽  
Ph Value ◽  
Zinc Carbonate ◽  
Leaching Solution ◽  
Optimized Conditions ◽  
Melting Slag

Brass melting slag (20.38 wt.% Zn) was leached in sulfuric acid with concentration of (50 + 80) g/l H2SO4, leaching temperature of (30 + 60) °C for (30 + 120) min. The optimized conditions for 94.16% Zn extraction from brass melting slag were found as 70 g/l H2SO4, room temperature and 90 min. The leaching solution was purified by removal of Fe through Fe(OH)3 precipitation when adding ZnO to adjust pH value of 5. The solution was continuously cemented by Zn metal at 60 °C for 60 min to obtain Cu metal with high purity of 99 wt.% Cu. The purified solution with 37.64 g/l Zn was modified by Na2C03 to have pH value of about 6 and precipitation of ZnC03 (94.14 %).

Recovery Gemanium from Pulverized Fuel Ash through the Method of H2SO4-NH4F-NaClO3 - Leaching-Tannin Precipitation

2013 ◽  
Vol 669 ◽  
pp. 377-383
Author(s):  
Shi Kun Pu ◽  
Yao Zhong Lan ◽  
Yan Jun Li ◽  
Zhong Hui Zhang
Keyword(s):  
Sulfuric Acid ◽  
Hydrochloric Acid ◽  
Acid Solution ◽  
Ammonium Fluoride ◽  
Sodium Chlorate ◽  
Sulphuric Acid Solution ◽  
Fuel Ash ◽  
Pulverized Fuel ◽  
Leaching Solution ◽  
Pulverized Fuel Ash

This paper will conduct a systematic study on method of recovering Ge from pulverized fuel ash in Lincang prefecture, Yunnan province. Details are like this, in view of the fact that Ge contained in pulverized fuel ash is wrapped up by a lot of Silica, Cao, magnesium oxide and is difficult to react with hydrochloric acid, so, first, have the pulverized fuel ash grinded to 200 meshes; then, ammonium fluoride should be put into 85-90°Cdilute sulphuric acid solution to produce hydrogen fluoride so as to destroy silicon dioxide and calcium oxide contained in the pulverized fuel ash. Meanwhile, dilute sulphuric acid solution dissolves magnesium oxide, by doing so, Ge will be released to react with sulfuric acid and produce Sulfuric acid Ge, and Ge will go into the solution；as for low state Ge（e.g,GeO,GeS）contained in the pulverized fuel ash which is difficult to be dissolved by sulfuric acid, sodium chlorate will be used as a kind of oxidant to change bivalence Ge into tetravalence Ge, then dissolve it into the solution, after the liquid-solid separation, sulfuric acid leaching solution rich in Ge will be obtained. Then, tannic acid will be used as precipitant to recover Ge from the leaching solution, and Ge concentrate will be produced through distillation and roasting. After this, put Ge concentrate on hydrochloric acid distillation to get germanium tetrachloride, After going through strenuous evaporation, distillation and hydrolysis, germanium dioxide with high purity will be yield. This paper has conducted conditional tests and discussion on the process parameters which will influence recovery Ge from pulverized fuel ash, including the dosage of Sulfuric acid, ammonium fluoride, sodium chlorate ,tannic acid and extraction time to find out the prior controlling condition of Ge recovery，under this prior condition, Ge leaching rate is as high as 84%，and tannic sinking Ge rate is as high as 98%. The pulverized fuel ash, after recovering Ge, can be used to backfill the mine pit, besides, most of the lixivium after recovering Ge can be recycled, and the rest of it will be released after neutralized up to the standard by lime. This process enjoys the following quality: high Ge recovery rate, less time used during the process ,less consumption of auxiliary material, easier to control the process, avoiding the potential pollution on the environment and lower cost involved in it, therefore, which is a kind of efficient and economic process of recovering Ge from pulverized fuel ash.

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