Ammonia Leaching Study on Refractory Oxidised Copper Ores

2014 ◽  
Vol 563 ◽  
pp. 53-56
Author(s):  
Tie Min Zhang ◽  
Zhi Cong Wei ◽  
Ying Bo Mao
Keyword(s):  
Yunnan Province ◽  
Fluoride Concentration ◽  
Ammonium Fluoride ◽  
Ammonia Concentration ◽  
Optimum Conditions ◽  
Solid Ratio ◽  
Binding Rate ◽  
Temperature And Pressure ◽  
Ammonia Leaching ◽  
Copper Ores

Ammonia leaching research is carried out on a certain oxidised copper ores. The effects of oxidized copper ores which came from Yunnan Province were studied in laboratory in order to find out the optimum leaching conditions under normal temperature and pressure. The ores belonged to typical high binding rate minerals. The optimum conditions obtained were as follows: granding fineness about 90% -0.074mm, ammonia concentration 2 mol/l, ammonium fluoride concentration 1.5mol/l , leaching time 2h, and liquid-solid ratio 3:1.The leaching rate of this ore could reach 86%.

Ammonia Leaching Study on Carbonate Oxidised Copper Ores in Yunnan

2015 ◽  
Vol 723 ◽  
pp. 644-647
Author(s):  
Ke Jun Bi ◽  
Jian Jun Fang ◽  
Tai Guo Jiang ◽  
Guo Dong Li
Keyword(s):  
Yunnan Province ◽  
Ammonia Concentration ◽  
Leaching Rate ◽  
Experimental Conditions ◽  
Solid Ratio ◽  
Copper Leaching ◽  
Temperature And Pressure ◽  
Ammonia Leaching ◽  
Copper Ores ◽  
Validation Experiments

The effects of oxidized copper ores which came from Yunnan province were carried out by using ammonialeaching methods in the laboratory.In order to seek the optimum leaching conditions under normal temperature and pressure,we conducted a series of validation experiments. Theoptimum conditions were obtained as follows: ammonia concentration 2.5mol/L, ammonium sulfateconcentration 2.5mol/L,grinding fineness about 80% -0.074mm, liquid-solid ratio 2.5:1and leaching time was 2.5h. Under these experimental conditions, the copper leaching rate could reach 69.91%.

Influence of Important Factors on Ammonia Leaching of Alkaline Zinc Oxide Mineral

2013 ◽  
Vol 785-786 ◽  
pp. 1076-1080
Author(s):  
Xiao Dong Jia ◽  
Zhi Cong Wei ◽  
Dian Wen Liu ◽  
Jing Jie Yuan
Keyword(s):  
Zinc Oxide ◽  
Yunnan Province ◽  
Ammonia Concentration ◽  
Ammonium Bicarbonate ◽  
Leaching Rate ◽  
Optimum Conditions ◽  
Liquid Ratio ◽  
Oxide Mineral ◽  
Ammonia Leaching

The effects of refractory zinc oxide ore which came from Lanping of Yunnan Province were studied using agitation leach method in laboratory in order to find out the optimum leaching conditions. The optimum conditions obtained are as follows: ammonia concentration 3mol/L, ammonium bicarbonate 1.5mol/L, granularity (-0.074mm) about 85%, solid to liquid ratio 4:1, and leaching time 2h. On this condition, the test obtained the better index of the zinc leaching rate 74.4%.

Research and Industry Application of New Process of Low Copper Oxide Ore

2013 ◽  
Vol 634-638 ◽  
pp. 3454-3459
Author(s):  
Ya Wen ◽  
Jian Jun Fang ◽  
Ying Bo Mao ◽  
Shan Wang ◽  
Zhi Cong Wei ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Yunnan Province ◽  
Electrode Position ◽  
Flotation Process ◽  
New Process ◽  
Temperature And Pressure ◽  
Ammonia Leaching ◽  
Technology Indicators ◽  
Extraction Electrode

The experiments of refractory copper oxide ore which comes from Tangdan of Yunnan Province were studied in laboratory using bulk flotation process and a new process that Ammonia leaching-Extraction-Electrode position-Residue flotation under normal temperature and pressure respectively. The results show that new process, compared with bulk flotation, had an effect to add 10.8 percent points to recovery. And then it is confirmed by industry experiment. So it is successfully applied to industry production and technology indicators were improved dramatically.

Ammonia Leaching of Zinc from Low-grade Oxide Zinc Ores Using the Enhancement of the Microwave Irradiation

2017 ◽  
Vol 16 (3) ◽  
Author(s):  
Shiwei Li ◽  
Haoyu Li ◽  
Weiheng Chen ◽  
Jinhui Peng ◽  
Aiyuan Ma ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Microwave Irradiation ◽  
Solid Phase ◽  
Ammonia Concentration ◽  
Low Grade ◽  
Leaching Rate ◽  
Small Particles ◽  
Mineral Phase ◽  
Total Ammonia ◽  
Ammonia Leaching

AbstractIrradiated roast treatment and the ammonia leaching processing were conducted to deal with the low-grade oxide zinc ores. The ZnCO3phase was hard to be attended, which was the reason for the low leaching rate of the complicated zinc ores. The mineral phase transformation of the ZnCO3phase was generated after the ores irradiated in the microwave at the temperature of 673 K. The irradiated ores generated more small particles, it was the reason that the leaching rate of the complicated zinc ores was increased. When the leaching processing of the irradiated roasted ores was conducted under the conditions of the total ammonia concentration of 6 mol/L, the liquid to solid phase ratio of 11:1, the leaching temperature of 298 K, the leaching time of 150 min and the stirring speed of 400 rpm, 88.3 % of zinc could be achieved, which was the maximum leaching rate of the irradiated ores.

Structural and Optical Properties of F-Doped ZnO Nanoparticles Synthesized by Co-Precipitation Process

2016 ◽  
Vol 675-676 ◽  
pp. 69-72
Author(s):  
Krisana Chongsri ◽  
Wanichaya Mekprasart ◽  
Wisanu Pecharapa
Keyword(s):  
Zno Nanoparticles ◽  
Fluoride Concentration ◽  
Precursor Solution ◽  
Hexagonal Wurtzite Structure ◽  
Ammonium Fluoride ◽  
Zinc Nitrate ◽  
Precipitation Process ◽  
Vis Spectroscopy ◽  
Doped Zno ◽  
Co Precipitation

In this work, we reported the preparation of F-doped ZnO nanoparticles by facile precipitation process using zinc nitrate and ammonium fluoride as starting precursors for Zn and F, respectively dissolved in deionized water. The precursor solution was prepared at various fluoride composition ranging from 1-5 wt%. The as-precipitated powders were calcined at different temperature from 500 °C to 700 °C for 2 h. Effect of calcination temperature and fluoride concentration on structural, morphologies, optical and electrical properties were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis spectroscopy, respectively. XRD results indicated the complete formation of hexagonal wurtzite structure of ZnO. SEM micrographs showed the agglomeration for each sample that noticeably influenced by fluoride content.

scholarly journals Removal of Fluoride from Drinking Water by Sorption Using Diatomite Modified with Aluminum Hydroxide

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Tesfaye Akafu ◽  
Achalu Chimdi ◽  
Kefyalew Gomoro
Keyword(s):  
Aluminum Hydroxide ◽  
Contact Time ◽  
Fluoride Concentration ◽  
Freundlich Isotherm ◽  
Intraparticle Diffusion ◽  
Fluoride Removal ◽  
Contaminated Water ◽  
Optimum Conditions ◽  
Intraparticle Diffusion Model ◽  
Adsorbent Dose

Exposure to fluoride beyond the recommended level for longer duration causes both dental and skeletal fluorosis. Thus, the development of cost-effective, locally available, and environmentally benign adsorbents for fluoride removal from contaminated water sources is absolutely required. In the present study, diatomaceous earth (diatomite) locally available in Ethiopia, modified by treating it with an aluminum hydroxide solution, was used as an adsorbent for fluoride removal from aqueous solutions. Adsorption experiments were carried out by using batch contact method. The adsorbent was characterized using FT-IR spectroscopy. Effects of different parameters affecting efficiency of fluoride removal such as adsorbent dose, contact time, initial fluoride concentration, and pH were investigated and optimized. The optimum adsorbent dose, contact time, initial fluoride concentration, and pH values were 25 g/L, 180 min, 10 mg/L, and 6.7, respectively. The performance of the adsorbent was also tested under optimum conditions using groundwater samples taken from Hawassa and Ziway. Langmuir and Freundlich isotherm models were applied to describe the equilibrium data. Compared to Langmuir isotherm (R2 = 0.888), the Freundlich isotherm (R2 = 0.985) model was better fitted to describe the adsorption characteristics of fluoride on Al-diatomite. The Langmuir maximum adsorption capacity was 1.67 mg/g. The pseudosecond-order model was found to be more suitable than the pseudofirst-order to describe the adsorption kinetics. The low correlation coefficient value of R2 = 0.596 for the intraparticle diffusion model indicates that the intraparticle diffusion model does not apply to the present studied adsorption system. The maximum fluoride removal was observed to be 89.4% under the optimum conditions which indicated that aluminum hydroxide-modified diatomite can be used as efficient, cheap, and ecofriendly adsorbents for the removal of fluoride from contaminated water.

scholarly journals Recovery of Silicon Dioxide from Waste Foundry Sand and Alkaline Activation of Desilicated Foundry Sand

2020 ◽  
Vol 6 (4) ◽  
pp. 700-714
Author(s):  
Tebogo Mashifana ◽  
Thandiwe Sithole
Keyword(s):  
Potassium Hydroxide ◽  
Solution Concentration ◽  
Curing Temperature ◽  
Strength Development ◽  
Waste Generation ◽  
Optimum Conditions ◽  
Foundry Sand ◽  
Solid Ratio ◽  
Waste Foundry Sand ◽  
Alkaline Activator

Abstract This study was conducted to recover silica (desilication) as a valuable metalloid from waste foundry sand (WFS) by a leaching process and to find application for desilicated foundry sand (DFS). The leaching time applied was 5 h; 3 M of potassium hydroxide (KOH) was used as a leaching reagent. The agitation speed of 200 rpm and the liquid/solid ratio of 25 were found to be the best conditions for optimum leaching results. A geopolymer from DFS was developed by using NaOH as an alkaline activator. The results obtained showed that the optimum conditions for the synthesis of a geopolymer were 15 M NaOH, 150 µm DFS particle size, and a curing temperature of 80 ℃ for 72 h. The geopolymer strength development was due to the formation of Phillipsite and Kalsilite as new hydration products. At the optimum alkaline solution concentration, the highest unconfined compressive strength (UCS) of 4.8 MPa was achieved. The developed geopolymer met the minimum strength requirements for load bearing material. This study provides an innovative and novel solution for the beneficiation of spent foundry sand and the recovery of a valuable metalloid, resulting to zero waste generation. Graphical Abstract

Biocatalytic and chemical leaching of a low-grade nickel laterite ore

2018 ◽  
Vol 115 (3) ◽  
pp. 305 ◽  
Author(s):  
Hasan Ciftci ◽  
Suleyman Atik ◽  
Fatma Gurbuz
Keyword(s):  
Sucrose Concentration ◽  
Low Grade ◽  
Optimum Conditions ◽  
Nickel Laterite ◽  
Chemical Leaching ◽  
Solid Ratio ◽  
Metals Recovery ◽  
Nickel Laterite Ore ◽  
The Difference ◽  
Laterite Ore

Nickel and cobalt recovery from a low-grade nickel laterite ore, supplied from Çaldağ deposit (Manisa, Turkey) were investigated by bio and chemical leaching processes. The fungus, Aspergillus niger was used for biocatalytic leaching experiments. The effects of parameters (solid ratio and sucrose concentration) on the biocatalytic leaching of the ore were initially tested in flasks to obtain the optimum conditions for the A. niger. Then chemical leaching was applied as a comparison to bioleaching, using organic acids (citric, oxalic, acetic and gluconic acids) as well as a mixture of acids. According the results, the maximum dissolution yield of nickel, cobalt and iron were detected respectively as 95.3%, 74.3% and 50.0% by biocatalytic processes which containing 25% (w/v) sucrose and 1% (w/v) solids. The increase in the solid ratio adversely influenced the biocatalytic activity of A. niger. Finally, further tests in reactors (v = 1 and 10 L) were performed using the optimum conditions from the flask tests. The difference in metals recovery between biocatalytic and chemical leaching was significantly important. Bioleaching produced higher Ni and Co extractions (34.3–75.6%) than chemical process.

Defluoridation of Groundwater Using Raw Material of Autoclaved Aerated Concrete

2017 ◽  
Vol 866 ◽  
pp. 99-103
Author(s):  
Woravith Chansuvarn
Keyword(s):  
Contact Time ◽  
Chemical Interaction ◽  
Fluoride Concentration ◽  
Batch Process ◽  
Raw Material ◽  
Optimum Conditions ◽  
Adsorption Method ◽  
Autoclaved Aerated Concrete ◽  
Aerated Concrete ◽  
Adsorbent Dose

A batch process of defluoridation using raw material of autoclaved aerated concrete (AAC) was studied under optimum conditions. The parameters of adsorption method, such as pH, adsorbent dose and contact time were optimized under batch experiments. SPADNS method was used to quantitatively evaluate the residual fluoride concentration. Under optimum conditions, pH of solution, adsorbent dose and contact time was to be 7, 0.1 g/10 mL and 60 min, respectively. The amount of defluoridation was found to be 3.23 mgF-/gACC. Deflouridation capacity of AAC can be explained on the basis of the chemical interaction of fluoride with the metal oxides under suitable pH conditions. The adsorption process was found to follow first order rate mechanism as well as Freundlich isotherm.

Impacts of ultrasound on leaching recovery of zinc from low grade zinc oxide ore

2015 ◽  
Vol 4 (4) ◽  
Author(s):  
Shiwei Li ◽  
Weiheng Chen ◽  
Shaohua Yin ◽  
Aiyuan Ma ◽  
Kun Yang ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Ammonia Concentration ◽  
Low Grade ◽  
Total Ammonia ◽  
Ammonia Leaching

AbstractOn the basis of an experiment on ultrasonic enhanced ammonia leaching of low grade zinc oxide ores, the effects of the total ammonia concentration, the ratio between the NH

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