There exists the most important REE-bearing phosphorite deposit in Southwest of China. Due to the fact that the REE are present in the form of ions in the lattices of collophanite or carbonatfluorapatite, the REE can ...There exists the most important REE-bearing phosphorite deposit in Southwest of China. Due to the fact that the REE are present in the form of ions in the lattices of collophanite or carbonatfluorapatite, the REE can be enriched in phosphate concentrate by flotation method. The phosphate concentrate is the main raw materials to produce phosphoric acid, therefore, it is significant to further investigate the distribution rule of REE in wet process. In this paper, the single leaching and recycled leaching technology were carried out to investigate the effect of various parameter conditions on distribution of REE in products. The REE compositions of products were analyzed by Inductively Coupled Plasma Emission Mass Spectrometry (ICP-MS) method. It was found that the acidic value of leaching liquor was the main effect factor on the distribution of REE in products. In single leaching stage, P2O5 concentration of leaching liquor slightly varied from 8% to about 10% when the excessive coefficient of sulphuric acid ranged from 1.03 to 1.05, and the distribution proportions of ∑REO in phosphoric acid solution was lower than 40%. However, in recycled leaching process(the condition similar to practical wet process), with an increase of P2O5 concentration as well as the acidic value of leaching liquor, the distribution proportions of ∑REO in phosphoric acid solution could be decreased to 2.56%. That is to say that under the condition similar to practical wet process, more than 90% of REE of phosphate concentrate became precipitation entering into the phosphogypsum product. This investigation will provide valid reference for reasonably recovering or reserving REE in wet-phosphoric acid process.展开更多
Phosphoric acid obtained by the wet process is laden with impurities which limit its use in fertilizers. To expand its range of use, various methods have been proposed to purify it which range from simple fading-clari...Phosphoric acid obtained by the wet process is laden with impurities which limit its use in fertilizers. To expand its range of use, various methods have been proposed to purify it which range from simple fading-clarification to more complex operations. These processes include essentially the liquid-liquid extraction, chemical precipitation, ion flotation, adsorption on activated carbon, ion exchange resins. However, the use of these techniques is limited to a number of disadvantages such as high operational cost, environmental pollution, complicated process, limited effectiveness, etc.. Our contribution for this domain （purification of wet-phosphoric acid） consists to use clays which could be adsorbent materials alternative to both economic and less polluting. These are phyllosilicates which have a large adsorption capacity due to their large specific surface and their surface charge. In this study, we will detail the processes which present great importance for the treatment of wet phosphoric acid.展开更多
Solvent extraction experiments were conducted from acidic solutions containing germanium（IV） and other metal ions, such as Ga3＋, Fe3＋, Zn2＋ and Fe2＋ in hydrometallurgical process of zinc. The purpose of this wor...Solvent extraction experiments were conducted from acidic solutions containing germanium（IV） and other metal ions, such as Ga3＋, Fe3＋, Zn2＋ and Fe2＋ in hydrometallurgical process of zinc. The purpose of this work was to enhance the efficiency of the extraction and stripping processes and the selectivity of germanium and other metals, while making the method as simple as possible. Germanium was recovered from sulfuric acid, using di-（2-ethylhexyl） phosphoric acid （P2O4） as an extractant, tributyl phosphate （TBP） as modifier diluted in sulfonate kerosene and stripped by NaOH aqueous solution. Extraction studies were carried out under different acid concentrations and solvent concentrations, and optimized conditions were determined. The numbers of stages required for extraction and stripping of metal ions were determined from the McCabe-Thiele plot. The results show that the extracting and stripping efficiencies are 94.3% and 100%, respectively, through two-stage extraction and two-stage strip. Moreover, the synergistic effect of TBP on the system P2O4/kerosense/Ge4＋ is revealed with respect to the extraction of germanium.展开更多
Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation ex...Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation exchange resin for iron removal from phosphoric acid. The specific surface area and the total exchange capacity of resin were 8.91 m2·g-1 and 5.18 mmol·g-1, respectively. The sorption mechanism was determined by FTIR and XPS and the results indicated that iron was combined with-SO3 H in resin. The removal process was studied as a function of temperature, H3 PO4 content and mass ratio between resin and solution. The unit mass of resin to remove iron was 0.058 g·g-1 resin when the operating parameters were T = 50 ℃, H3 PO4 content = 27.61 wt%and S/L = 0.1, respectively. Kinetics study demonstrated that pseudo-second-order reaction model fits this study best and the calculated activation energy of overall reaction is 29.10 kJ·mol-1. The overall reaction process was mainly controlled by pore diffusion.展开更多
The extraction of zinc from zinc sulfate solution was investigated, using 20% saponified D2EHPA as an extractam and 260^# sulfonate kerosene as a diluent. The solution was stirred for 8 min at phase ratio （Vσ/Va） o...The extraction of zinc from zinc sulfate solution was investigated, using 20% saponified D2EHPA as an extractam and 260^# sulfonate kerosene as a diluent. The solution was stirred for 8 min at phase ratio （Vσ/Va） of 1.0：1.0, initial pH of 2.0 and stirring speed of 200 r/min. The results show that 75% zinc can be extracted from the zinc sulfate solution when the concentration of zinc is 18.7 g/L after being settled for 10 min. 88.60% zinc can be stripped by 196 g/L sulfuric acid, and zinc ion can be separated from ferric ion.展开更多
The phosphorous mixer introduced could replace D2EHPA as an extractant applied in the extraction of indium. The extraction properties of the phosphorous mixer were studied. The influences of extractant concentration, ...The phosphorous mixer introduced could replace D2EHPA as an extractant applied in the extraction of indium. The extraction properties of the phosphorous mixer were studied. The influences of extractant concentration, organic/aqueous (O/A) phase ratio, equilibrium time, and pH value of the feed solutions on the extraction of indium, and separation of indium-iron were investigated experimentally. Under the best operating conditions, more than 98% of indium. was extracted through two-stage counter-current extraction. The optimizing condition of indium extraction is determined as follows: O/A = 1 : (9-12) in volume ratio; 30% PPD in sulphonated kerosene; pH of the feed, about 0.6; equilibrium time, 3-5 min. The extractant has good reusing and anti-aging properties.展开更多
In this work, a novel room temperature ionic liquid (2-butyl-imidazolium di-(2-ethylhexyl) phosphate) ([C4mim] [D2EHPA]) was synthesized and tested as extractant in the mercury(II) liquid-liquid extraction. The effect...In this work, a novel room temperature ionic liquid (2-butyl-imidazolium di-(2-ethylhexyl) phosphate) ([C4mim] [D2EHPA]) was synthesized and tested as extractant in the mercury(II) liquid-liquid extraction. The effects of parameters such as aqueous to organic phase’s volume ratio, metal concentration IL concentration, pH levels, ionic strength, and temperature were reported. For the extraction of metal, [C4mim]3[R.HR]3[HgCl2]org and [C4mim]3[R.HR]3 [HgClOH]org species were formed where (H2R2) was D2EHPA. In the case of ionic strength, the results showed that the addition of sodium acetate at 0.302 mmol·L?1 to the aqueous phase strongly increased the mercury extraction yield (R = 100%). The extracted species were investigated by a calculation program using CHEAQS V. L20.1 inorder to determine the relation between the percentages of the extracted species and the extraction yield. The results showed that the extracted species in the best conditions were HgCl2 and HgClOH with respective percentages 80.66% and 18.29%.展开更多
基金the Natural Science Foundation of Guizhou Province (QianKeHe J[2005]2098)
文摘There exists the most important REE-bearing phosphorite deposit in Southwest of China. Due to the fact that the REE are present in the form of ions in the lattices of collophanite or carbonatfluorapatite, the REE can be enriched in phosphate concentrate by flotation method. The phosphate concentrate is the main raw materials to produce phosphoric acid, therefore, it is significant to further investigate the distribution rule of REE in wet process. In this paper, the single leaching and recycled leaching technology were carried out to investigate the effect of various parameter conditions on distribution of REE in products. The REE compositions of products were analyzed by Inductively Coupled Plasma Emission Mass Spectrometry (ICP-MS) method. It was found that the acidic value of leaching liquor was the main effect factor on the distribution of REE in products. In single leaching stage, P2O5 concentration of leaching liquor slightly varied from 8% to about 10% when the excessive coefficient of sulphuric acid ranged from 1.03 to 1.05, and the distribution proportions of ∑REO in phosphoric acid solution was lower than 40%. However, in recycled leaching process(the condition similar to practical wet process), with an increase of P2O5 concentration as well as the acidic value of leaching liquor, the distribution proportions of ∑REO in phosphoric acid solution could be decreased to 2.56%. That is to say that under the condition similar to practical wet process, more than 90% of REE of phosphate concentrate became precipitation entering into the phosphogypsum product. This investigation will provide valid reference for reasonably recovering or reserving REE in wet-phosphoric acid process.
文摘Phosphoric acid obtained by the wet process is laden with impurities which limit its use in fertilizers. To expand its range of use, various methods have been proposed to purify it which range from simple fading-clarification to more complex operations. These processes include essentially the liquid-liquid extraction, chemical precipitation, ion flotation, adsorption on activated carbon, ion exchange resins. However, the use of these techniques is limited to a number of disadvantages such as high operational cost, environmental pollution, complicated process, limited effectiveness, etc.. Our contribution for this domain （purification of wet-phosphoric acid） consists to use clays which could be adsorbent materials alternative to both economic and less polluting. These are phyllosilicates which have a large adsorption capacity due to their large specific surface and their surface charge. In this study, we will detail the processes which present great importance for the treatment of wet phosphoric acid.
基金Project(50774094)supported by the National Natural Science Foundation of China
文摘Solvent extraction experiments were conducted from acidic solutions containing germanium（IV） and other metal ions, such as Ga3＋, Fe3＋, Zn2＋ and Fe2＋ in hydrometallurgical process of zinc. The purpose of this work was to enhance the efficiency of the extraction and stripping processes and the selectivity of germanium and other metals, while making the method as simple as possible. Germanium was recovered from sulfuric acid, using di-（2-ethylhexyl） phosphoric acid （P2O4） as an extractant, tributyl phosphate （TBP） as modifier diluted in sulfonate kerosene and stripped by NaOH aqueous solution. Extraction studies were carried out under different acid concentrations and solvent concentrations, and optimized conditions were determined. The numbers of stages required for extraction and stripping of metal ions were determined from the McCabe-Thiele plot. The results show that the extracting and stripping efficiencies are 94.3% and 100%, respectively, through two-stage extraction and two-stage strip. Moreover, the synergistic effect of TBP on the system P2O4/kerosense/Ge4＋ is revealed with respect to the extraction of germanium.
基金Supported by the National Basic Research Program of China(2016YFD0200404)
文摘Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation exchange resin for iron removal from phosphoric acid. The specific surface area and the total exchange capacity of resin were 8.91 m2·g-1 and 5.18 mmol·g-1, respectively. The sorption mechanism was determined by FTIR and XPS and the results indicated that iron was combined with-SO3 H in resin. The removal process was studied as a function of temperature, H3 PO4 content and mass ratio between resin and solution. The unit mass of resin to remove iron was 0.058 g·g-1 resin when the operating parameters were T = 50 ℃, H3 PO4 content = 27.61 wt%and S/L = 0.1, respectively. Kinetics study demonstrated that pseudo-second-order reaction model fits this study best and the calculated activation energy of overall reaction is 29.10 kJ·mol-1. The overall reaction process was mainly controlled by pore diffusion.
基金Project(50774094) supported by the National Natural Science Foundation of China
文摘The extraction of zinc from zinc sulfate solution was investigated, using 20% saponified D2EHPA as an extractam and 260^# sulfonate kerosene as a diluent. The solution was stirred for 8 min at phase ratio （Vσ/Va） of 1.0：1.0, initial pH of 2.0 and stirring speed of 200 r/min. The results show that 75% zinc can be extracted from the zinc sulfate solution when the concentration of zinc is 18.7 g/L after being settled for 10 min. 88.60% zinc can be stripped by 196 g/L sulfuric acid, and zinc ion can be separated from ferric ion.
文摘The phosphorous mixer introduced could replace D2EHPA as an extractant applied in the extraction of indium. The extraction properties of the phosphorous mixer were studied. The influences of extractant concentration, organic/aqueous (O/A) phase ratio, equilibrium time, and pH value of the feed solutions on the extraction of indium, and separation of indium-iron were investigated experimentally. Under the best operating conditions, more than 98% of indium. was extracted through two-stage counter-current extraction. The optimizing condition of indium extraction is determined as follows: O/A = 1 : (9-12) in volume ratio; 30% PPD in sulphonated kerosene; pH of the feed, about 0.6; equilibrium time, 3-5 min. The extractant has good reusing and anti-aging properties.
文摘In this work, a novel room temperature ionic liquid (2-butyl-imidazolium di-(2-ethylhexyl) phosphate) ([C4mim] [D2EHPA]) was synthesized and tested as extractant in the mercury(II) liquid-liquid extraction. The effects of parameters such as aqueous to organic phase’s volume ratio, metal concentration IL concentration, pH levels, ionic strength, and temperature were reported. For the extraction of metal, [C4mim]3[R.HR]3[HgCl2]org and [C4mim]3[R.HR]3 [HgClOH]org species were formed where (H2R2) was D2EHPA. In the case of ionic strength, the results showed that the addition of sodium acetate at 0.302 mmol·L?1 to the aqueous phase strongly increased the mercury extraction yield (R = 100%). The extracted species were investigated by a calculation program using CHEAQS V. L20.1 inorder to determine the relation between the percentages of the extracted species and the extraction yield. The results showed that the extracted species in the best conditions were HgCl2 and HgClOH with respective percentages 80.66% and 18.29%.
