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Intensified reactive extraction of 4-hydroxypyridine with di(2-ethylhexyl) phosphoric acid in 1-octanol by using tributyl phosphate
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作者 Zhixian Chang Xiangfeng Zhou +2 位作者 Huihua Bai Deliang Li Ling Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期199-205,共7页
The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl pho... The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent. 展开更多
关键词 4-Hydroxypyridine Di(2-ethylhexyl)phosphoric acid Tributyl phosphate Reactive extraction Intensified extraction
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Flotation behavior and adsorption mechanism of(1-hydroxy-2-methyl-2-octenyl) phosphonic acid to cassiterite 被引量:15
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作者 谭鑫 何发钰 +1 位作者 尚衍波 印万忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2469-2478,共10页
The flotation behavior and adsorption mechanism of novel(1-hydroxy-2-methyl-2-octenyl) phosphonic acid(HEPA) to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determinati... The flotation behavior and adsorption mechanism of novel(1-hydroxy-2-methyl-2-octenyl) phosphonic acid(HEPA) to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determination and density functional theory(DFT) calculation. The flotation results demonstrated that HEPA exhibited superior collecting performance compared with styrene phosphonic acid(SPA). The cassiterite recovery maintained above 90% over a wide pH range of 2-9 with 50 mg/L HEPA. The results of zeta potential measurement and FTIR detection indicated that the adsorption of HEPA onto cassiterite was mainly attributed to the chemisorption between HEPA monoanions and Sn species on mineral surfaces. The DFT calculation results demonstrated that HEPA monoanions owned higher HOMO energy and exhibited a better affinity to cassiterite than SPA, which provided very clear evidence for the stronger collecting power of HEPA presented in floatation test and zeta potential measurement. 展开更多
关键词 (1-hydroxy-2-methyl-2-octenyl) phosphonic acid CASSITERITE adsorption FLOTATION density functional theory
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Adsorption of Cr(Ⅵ) in Water with Phosphoric Acid Modified and Ordinary Walnut Shells
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作者 鲁秀国 段建菊 黄燕梅 《Agricultural Science & Technology》 CAS 2015年第9期1989-1993,共5页
A comparison between the effects of ordinary walnut shell and phosphoric acid modified walnut shell on adsorption of Cr(Ⅵ) was carried out. The experimental results showed that owing to larger surface void of modif... A comparison between the effects of ordinary walnut shell and phosphoric acid modified walnut shell on adsorption of Cr(Ⅵ) was carried out. The experimental results showed that owing to larger surface void of modified walnut shell its adsorption of Cr(Ⅵ) was better. When the temperature was 35 ℃, adsorbent particle size was 1.0-1.6 mm, shaker shock rate was 200 r/min, and dosage of walnut shell was 0.80 g, the Cr(Ⅵ) removal rate reached 99.4%. The fitting of adsorption isotherm and kinetics model showed that, Langmuir isotherm model could reflect the adsorption process of modified walnut shell; and both the adsorption processes of ordinary and modified walnut shells accorded with the pseudo-second-order kinetic equations. 展开更多
关键词 phosphoric acid modification ADSORPTION Walnut shell Cr(Ⅵ)
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三元混配化合物的极谱研究──Phosphonic-、Amino-acid-Eu体系稳定性
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作者 刘新文 卢小泉 《天水师范学院学报》 2001年第2期40-45,共6页
以脉冲极谱法研究了用有机磷酸和氨基酸作为配体与Eu(Ⅲ)形成两元及三元体系配合物的极谱行为.模拟生理条件,在μ=0.1(NaCl)、T=310±0.2K条件下,电极过程为准可逆;测定了配合物的稳定常数;讨论了复杂... 以脉冲极谱法研究了用有机磷酸和氨基酸作为配体与Eu(Ⅲ)形成两元及三元体系配合物的极谱行为.模拟生理条件,在μ=0.1(NaCl)、T=310±0.2K条件下,电极过程为准可逆;测定了配合物的稳定常数;讨论了复杂体系各配合物稳定性差异及其影响因素. 展开更多
关键词 有机酸 三元配合物 稳定常数 极谱法
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CORROSION BEHAVIOR OF A ZIRCONIUM-TITANIUM BASED PHOSPHONIC ACID CONVERSION COATING ON AA6061 ALUMINIUM ALLOY 被引量:11
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作者 S.H. Wang C.S. Liu F.J. Shan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第4期269-274,共6页
The conversion coating was formed by dipping AA6061 in a fluorotitanate/zirconate acid and amino trimethylene phosphonic acid (ATMP) solution at room temperature. The formation process and the anti-corrosion perform... The conversion coating was formed by dipping AA6061 in a fluorotitanate/zirconate acid and amino trimethylene phosphonic acid (ATMP) solution at room temperature. The formation process and the anti-corrosion performance of the conversion coating were investigated using electrochemical test and salt spray test (SST), respectively. The electrochemical test shows that the Zr/Ti and ATMP coating improves the corrosion resistance of AA6061 as good as the chromate (VI) coating. But the results of SST show that the corrosion resistance of Zr/Ti and ATMP coating is not as good as the chromate (VI) coating. The corrosion area is less than 2% after 72 h. 展开更多
关键词 Corrosion resistance Fluorotitanate/zireonate acid phosphonic acid Aluminium alloy Conversion coating
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Studies on Adsorption Behavior and Mechanism of Copper(Ⅱ) onto Amino Methylene Phosphonic Acid Resin 被引量:14
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作者 XIONGChun-hua WANGYong-jiang SHILin-mei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第3期366-369,共4页
The adsorption behavior and the mechanism of a novel chelate resin, amino methylene phosphonic acid resin(APAR) for Cu(Ⅱ) were investigated. Cu(Ⅱ) was quantitatively adsorbed by APAR in the medium of pH=4 09. The s... The adsorption behavior and the mechanism of a novel chelate resin, amino methylene phosphonic acid resin(APAR) for Cu(Ⅱ) were investigated. Cu(Ⅱ) was quantitatively adsorbed by APAR in the medium of pH=4 09. The statically saturated adsorption capacity is 181 mg/(g resin). Cu(Ⅱ) adsorbed on APAR can be eluted by 1 0-3 0 mol/L HCl. The rate constant is k 298 =5 58×10 -5 s -1 . The adsorption of Cu(Ⅱ) on APAR follows the Freundlich isotherm. The Δ H of the adsorption is 3 91 kJ/mol. The apparent activation energy is E a=21 4 kJ/mol. The coordination molar ratio of APAR to Cu(Ⅱ) is 1/1. It is shown that the nitrogen and the oxygen atoms in the functional group of APAR coordinate to Cu(Ⅱ). 展开更多
关键词 Amino methylene phosphonic acid resin COPPER ADSORPTION MECHANISM
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Arsenic removal from contaminated soil using phosphoric acid and phosphate 被引量:29
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作者 ZENG Min LIAO Bohan +3 位作者 LEI Ming ZHANG Yong ZENG Qingru OUYANG Bin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第1期75-79,共5页
Laboratory batch experiments were conducted to study arsenic (As) removal from a naturally contaminated soil using phosphoric acid (H3PO4) and potassium dihydrogen phosphate (KHEPO4). Both H3PO4 and KHEPO4 prove... Laboratory batch experiments were conducted to study arsenic (As) removal from a naturally contaminated soil using phosphoric acid (H3PO4) and potassium dihydrogen phosphate (KHEPO4). Both H3PO4 and KHEPO4 proved to reduce toxicity of the soil in terms of soil As content, attaining more than 20% As removal at a concentration of 200 mmol/L. At the same time, acidification of soil and dissolution of soil components (Ca, Mg, and Si) resulted from using these two extractants, especially H3PO4. The effectiveness of these two extractants could be attributed to the replacement of As by phosphate ions (PO4^3-). The function of H3PO4 as an acid to dissolve soil components had little effects on As removal. KH2PO4 almost removed as much As as H3PO4, but it did not result in serious damage to soils, indicating that it was a more promising extractant. The results of a kinetic study showed that As removal reached equilibrium after incubation for 360 rain, but dissolution of soil components, especially Mg and Ca, was very rapid. Therefore dissolution of soil components would be inevitable if As was further removed. Elovich model best described the kinetic data of As removal among the four models used in the kinetic study. 展开更多
关键词 arsenic (As) REMOVAL phosphoric acid (H3PO4) potassium dihydrogen phosphate (KH2PO4) chemical extraction
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Mechanism and kinetics study on removal of Iron from phosphoric acid by cation exchange resin 被引量:7
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作者 Xinke Leng Yanjun Zhong +2 位作者 Dehua Xu Xinlong Wang Lin Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1050-1057,共8页
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
关键词 PURIFICATION of wet-process phosphoric acid CATION EXCHANGE RESIN Kinetics MODELS Diffusion MODELS
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Centrifugal extraction of rare earths from wet-process phosphoric acid 被引量:8
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作者 WANG Liangshi YU Ying LIU Ying LONG Zhiqi 《Rare Metals》 SCIE EI CAS CSCD 2011年第3期211-215,共5页
Phosphorite ore is a potential resource of rare earths (RE) as well as phosphate; therefore, the recovery of RE from wet-process phosphoric acid (WPA) is promising. This study investigated the influence of rotatio... Phosphorite ore is a potential resource of rare earths (RE) as well as phosphate; therefore, the recovery of RE from wet-process phosphoric acid (WPA) is promising. This study investigated the influence of rotational speed, extractant concentration, flow ratio and phase contact time on the centrifugal extraction of RE from WPA and the separation of RE from impurities. The results indicate that higher rotational speed, higher extractant concentration and larger flow ratio are beneficial to the extraction of RE and impurities from phosphoric acid. It is found that the phase contact time for efficiently extracting RE and that for iron are of great difference, which provides an effective method for separating RE from iron using the non-equilibrium extraction process in centrifugal contactors. Compared with equilibrium extraction, the separation factor βRE/Fe is enhanced from 0.07 to 17.6. 展开更多
关键词 HYDROMETALLURGY centrifugal extraction rare earths phosphoric acid
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Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium 被引量:9
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作者 黄小卫 李建宁 +3 位作者 龙志奇 张永奇 薛向欣 朱兆武 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期410-413,共4页
The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric a... The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined. 展开更多
关键词 di-(2-ethylhexyl) phosphoric acid 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester synergistic extraction mechanism Sm^3+ Nd^3+ rare earths
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Sorption Behavior and Mechanism of Indium(Ⅲ) onto Amino Methylene Phosphonic Acid Resin 被引量:7
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作者 熊春华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2002年第2期47-50,共4页
The sorption behavior of amino methylene phosphonic acid resin (APAR) for In (Ⅲ ) was investigated . Experimental results show that In ( Ⅲ ) adsorbed on APAR can be elated with 2mol · L -1 HCl. The apparent rat... The sorption behavior of amino methylene phosphonic acid resin (APAR) for In (Ⅲ ) was investigated . Experimental results show that In ( Ⅲ ) adsorbed on APAR can be elated with 2mol · L -1 HCl. The apparent rate constant is k29 = 1.50 × 10-5s-1. The sorption behavior of APAR for In ( Ⅲ ) obeys the Freundlich isotherm. The themodynamic parameters of sorption, enthalpy change ()H, free energy change ()G and entropy change ()S of sorption (APAR) for In ( Ⅲ ) are 24.1 kJ·mol-1, -35. 1kJ· mol-1 and 200J· mol-1·K-1 respectively. The coordination molar ratio of the functional group of APAR to In( Ⅲ ) is 2:1. The sorption mechanism of APAR for In( Ⅲ ) was examined by IR spectrometry. 展开更多
关键词 Amino methylene phosphonic acid resin INDIUM sorption mechanism
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Insight into the formation mechanism of levoglucosenone in phosphoric acid-catalyzed fast pyrolysis of cellulose 被引量:4
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作者 Bin Hu Qiang Lu +5 位作者 Yu-ting Wu Wen-luan Xie Min-shu Cui Ji Liu Chang-qing Dong Yong-ping Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第4期78-89,共12页
The catalytic fast pyrolysis of cellulose impregnated with phosphoric acid (H3PO4) offers a promising method for the selective production of levoglucosenone (LGO),a valuable anhydrosugar product.However,the fundamenta... The catalytic fast pyrolysis of cellulose impregnated with phosphoric acid (H3PO4) offers a promising method for the selective production of levoglucosenone (LGO),a valuable anhydrosugar product.However,the fundamental mechanism for selective LGO formation is unclear.Herein,quantum chemistry calculations and catalytic fast pyrolysis experiments were performed to reveal the formation mechanism of LGO in H3PO4-catalyzed cellulose pyrolysis.H3PO4 significantly decreased the energy barriers of the pyrolytic reactions and altered the competitiveness of the LGO formation pathways,promoting LGO formation.Through different pathways in the non-catalytic and H3P04-catalyzed conditions,LGO is mainly produced from the primary decomposition of glucose units of cellulose and secondary conversion of levoglucosan.The major catalytic formation pathways of LGO comprise similar reactions,with dehydration at the 3-OH+2-H site as the rate-determining step.Importantly,secondary conversion of 1,4;3,6-dianhydro-α-D-glucopyranose is not feasible for LGO formation,in contrast to previous reports.In addition,a high degree of polymerization is beneficial for the selectivity of LGO formation in the catalytic process,because the glycosidic bond is important for the formation of the bicyclic structure (1,5-and1,6-acetal rings). 展开更多
关键词 phosphoric acid LEVOGLUCOSENONE Formation mechanism Density functional theory Py-GC/MS
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Hydrophobic flocculation flotation of rutile fines in presence of styryl phosphonic acid 被引量:10
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作者 Xiao-tao HUANG Wei XIAO +6 位作者 Hong-bo ZHAO Pan CAO Qi-xiu HU Wen-qing QIN Yan-sheng ZHANG Guan-zhou QIU Jun WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第7期1425-1433,共9页
The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid(SPA) was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based part... The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid(SPA) was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based particle size analysis, adsorption measurements and DLVO theory. The flotation tests indicated that rutile fines could be flocculated by SPA, and pH, shear force(stirring speed) and stirring time played significant roles in flocculation. The isoelectric point(IEP) and zeta-potential in whole range all moved to negative values as SPA was added according to the results from zeta-potential measurement. It was demonstrated that the primary reason for above was chemical adsorption. The laser-based particle size results showed the particle size at a stirring speed of 1800 r/min and 1000 mg/L SPA was the largest in all experiments. Furthermore, using the optical microscope observation and flotation tests, it was important for flotation of rutile fines to produce the flocculant. In the light of above-mentioned facts, floc flotation of rutile fines could be induced in the form of chemical adsorption by SPA to increase particle size. The data calculated from DLVO theory also indicated that chemical adsorption was the main reason for the formation of flocculant. 展开更多
关键词 hydrophobic flocculation flotation rutile fines styryl phosphonic acid(SPA) DLVO theory
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Leaching kinetics of calcium molybdate with hydrochloric acid in presence of phosphoric acid 被引量:5
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作者 Wen-juan ZHANG Cheng-yan WANG Bao-zhong MA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第4期859-867,共9页
Calcium molybdate(CaMoO4)is the main component of powellite and is a predominant intermediate in the pyrometallurgical and hydrometallurgical process of molybdenum.The extraction of Mo from CaMoO4 by a combination of ... Calcium molybdate(CaMoO4)is the main component of powellite and is a predominant intermediate in the pyrometallurgical and hydrometallurgical process of molybdenum.The extraction of Mo from CaMoO4 by a combination of phosphoric acid and hydrochloric acid was investigated.For further understanding of the leaching mechanism,the effects of five key factors were studied to describe the leaching kinetics.The results indicated that the dissolution rate of CaMoO4 was independent of the stirring speed.Mo extraction significantly increased with increasing HCl concentration and temperature,but decreased with increasing particle size.A shrinking core model with surface chemical reaction was found to withstand the dissolution of CaMoO4.The apparent activation energy was calculated to be 70.879 kJ/mol,and a semi-empirical equation was derived for the rate of reaction. 展开更多
关键词 calcium molybdate leaching kinetics phosphoric acid hydrochloric acid
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Adsorption of Macroporous Phosphonic Acid Resin for Nickel 被引量:2
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作者 熊春华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第4期16-19,共4页
Tje adsorption bchavior and mechanism of a novel chelate resin,macroporous phosphonic acid resin(PAR)for Ni(Ⅱ)were imestigated.The stotically saturated adsorption capacity is 64.3mg·g^-1 resin at 298K in HAc... Tje adsorption bchavior and mechanism of a novel chelate resin,macroporous phosphonic acid resin(PAR)for Ni(Ⅱ)were imestigated.The stotically saturated adsorption capacity is 64.3mg·g^-1 resin at 298K in HAc-NaAc medium.The Ni(Ⅱ)adsorbed on PAR can be eluted by 0.5mal·L^-1 HCl and the elution percentage reaches 96.6%.The resin can be regenerated and reused without abvious decrease in adsorption capacity.The apparent adsorption rate constant is k298=2.6×10^-5s^-1.The adsorption behavior of PAR for Ni(Ⅱ)obeys the Freundllich isotherm.The thermodynamie adsorption parameters.enthalpy change △H,free energy change △G and entropy change △S of PAR for Ni(Ⅱ)are 3.36kJ·mol^-1,-5.47kJ·mol^-1 and 29.6J·mol^-1·K^-1,respectively.The apparent activation energy is Ea=12.2kJ·mol^-1,The molar coordination ratio of the functional group of PAR to Ni(Ⅱ)is about 4:1.The adsorption mechanism of PAR for Ni(Ⅱ)was examined by a chemical method and IR spectrometry. 展开更多
关键词 macroporous phosphonic acid resin NICKEL ADSORPTION MECHANISM
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Adsorption equilibrium and kinetics studies of divalent manganese from phosphoric acid solution by using cationic exchange resin 被引量:4
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作者 Haibo Zhuang Yanjun Zhong Lin Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第11期2758-2770,共13页
There are numerous impurities in wet-process phosphoric acid,among which manganese is one of detrimental metallic impurities,and it causes striking negative effects on the industrial phosphoric acid production and dow... There are numerous impurities in wet-process phosphoric acid,among which manganese is one of detrimental metallic impurities,and it causes striking negative effects on the industrial phosphoric acid production and downstream commodity.This article investigated the adsorption behavior of manganese from phosphoric acid employing Sinco-430 cationic ion-exchange resin.Resorting FT-IR and XPS characterizations,the adsorption mechanism was proved to be that manganese was combined with sulfonic acid group.Several crucial parameters such as temperature,phosphoric acid content and resin dose were studied to optimize adsorption efficiency.Through optimization,removal percentage and sorption capacity of manganese reached 53.12 wt%,28.34 mg·g^-1,respectively.Pseudo-2nd-order kinetic model simulated kinetics data best and the activation energy was evaluated as 6.34 kJ·mol^-1 for the sorption reaction of manganese.In addition,the global adsorption rate was first controlled by film diffusion process and second determined by pore diffusion process.It was found that the resin could adsorb up to 50.24 mg·g^-1 for manganese.Equilibrium studies showed that Toth adsorption isotherm model fitted best,followed by Temkin and Langmuir adsorption isotherm models.Thermodynamic analysis showed that manganese adsorption was an endothermic process with enhanced randomness and spontaneity. 展开更多
关键词 MANGANESE Ion exchange phosphoric acid KINETICS ISOTHERM THERMODYNAMICS
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STUDIES ON THE SORPTION OF MACROPOROUS PHOSPHONIC ACID RESIN FOR LANTHANUM 被引量:24
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作者 Xiong Chunhua Su Zhengnian Chen Yiyong 《Chinese Journal of Reactive Polymers》 1998年第2期7-15,共9页
The influences of medium pH sorption temperature, sorption time, etc. on thesorption capacity of macroporous Phosphonic acid resin for La3+ were determined Thesorption rate constant was k298 = 7.64×10-5 s-1. The ... The influences of medium pH sorption temperature, sorption time, etc. on thesorption capacity of macroporous Phosphonic acid resin for La3+ were determined Thesorption rate constant was k298 = 7.64×10-5 s-1. The complex ratio of phosphonicgroups of the resin to La3+ was 3:1. The basic sorption parameters were determinedThe sorption mechanism of macroporous phosphonic acid resin for La3+ was examinedby chemical analysis and IR- spectrometry. 展开更多
关键词 LANTHANUM Macroporous phosphonic acid resin SORPTION MECHANISM
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Adsorption Behaviors and Mechanism of Macroporous PhosphonicAcid Resin for Gadolinium 被引量:2
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作者 吴香梅 熊春华 姚彩萍 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第6期785-789,共5页
The adsorption behaviors and mechanism of a novel chelate resin, macroporous phosphonic acid resin(PAR)for Gd(Ⅲ)were investigated. The statically and dynamically saturated adsorption capacity is respectively 308 mg&#... The adsorption behaviors and mechanism of a novel chelate resin, macroporous phosphonic acid resin(PAR)for Gd(Ⅲ)were investigated. The statically and dynamically saturated adsorption capacity is respectively 308 mg·g^(-1)resin and 296 mg·g^(-1)resin at 298 K in HAc-NaAc medium at pH 5.6. Gd(Ⅲ)adsorbed on PAR can be reductively eluted by 0.5~5.0 mol·L^(-1) HCl used as eluant and the elution percentage is up to 94.7% in 1.0 mol·L^(-1) HCl. The resin can be regenerated and reused without apparent decrease in adsorption capacity. The apparent adsorption rate constant is k_(298)=3.96×10^(-5) s^(-1). The adsorption behavior of PAR for Gd(Ⅲ) conforms to the Freundlich isotherm. The thermodynamic adsorption parameter, enthalpy change △H of PAR for Gd(Ⅲ)is 22.6kJ·mol^(-1). The apparent adsorption activation energy(Ea)of PAR for Gd(Ⅲ)is 5.0 kJ·mol^(-1). The molar coordination ratio of the functional group of PAR to Gd(Ⅲ)is about 3∶1. The adsorption mechanism of PAR for Gd(Ⅲ)was examined by using chemical method and IR spectrometry. 展开更多
关键词 macroporous phosphonic acid resin gadolinium adsorption mechanism rar earths
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Thermal stability and oil absorption of aluminum hydroxide treated by dry modification with phosphoric acid 被引量:3
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作者 周向阳 李昌林 +3 位作者 霍登伟 李劼 伍上元 刘业翔 《Journal of Central South University of Technology》 EI 2007年第6期779-782,共4页
The dry modification of aluminum hydroxide powders with phosphoric acid and the effects of modification of technological conditions on thermal stability, morphology and oil absorption of aluminum hydroxide powders wer... The dry modification of aluminum hydroxide powders with phosphoric acid and the effects of modification of technological conditions on thermal stability, morphology and oil absorption of aluminum hydroxide powders were investigated. The results show that the increase of mass ratio of phosphoric acid to aluminum hydroxide, the decrease of mass concentration of phosphoric acid and prolongation of mixing time are favorable to the improvement of thermal stability of aluminum hydroxide; when the mass ratio of phosphoric acid to aluminum hydroxide is 5:100, the mass concentration of phosphoric acid is 200 g/L and the mixing time is 10 min, the initial temperature of loss of crystal water in aluminum hydroxide rises from about 192.10 to 208.66 ℃, but the dry modification results in the appearance of agglomeration and macro-aggregate in the modified powders, and the oil absorption of modified powders becomes higher than that of original aluminum hydroxide. 展开更多
关键词 aluminum hydroxide phosphoric acid thermal stability oil absorption dry modification
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CFD investigation of the agitation in the desupersaturation during the wet-process phosphoric acid(WPPA)process 被引量:2
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作者 Asmaa Hadane Lhachmi Khamar +2 位作者 Saad Benjelloun Abderrahman Nounah Mohammed Khamar 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第8期2064-2074,共11页
Desupersaturation is a complex cooling operation that involves hydrodynamic,thermal and mechanical phenomena.This process requires continuous agitation to avoid fouling problems and sludge deposition.The current work ... Desupersaturation is a complex cooling operation that involves hydrodynamic,thermal and mechanical phenomena.This process requires continuous agitation to avoid fouling problems and sludge deposition.The current work aims to investigate the well mixedness in the desupersaturation tank for optimal performance.For this purpose,a multi-fluid CFD study was conducted based on the Euler–Euler modeling approach,considering a multiphase flow involving a liquid phase(phosphoric acid)and a poly-dispersed solid phase,i.e.a sludge with three different sizes where each size is considered as a separate phase.First,the hydrodynamic behavior of the flow within the agitated desupersaturator is analyzed through the investigation of the velocity fields as well as the power and pumping numbers,to determine both the agitator capacity to pump the flow and its power consumption during the operation.Then,in order to assess the mixture homogeneity,we evaluated the solid suspension in the desupersaturation reactor following conventional methods and two new proposed methodologies:the first approach is to evaluate the suspension quality in the mixing system by compartment and the second consists on the assessment of the uniform convergence of the solid concentration.Furthermore,we calculated the time required to achieve a full suspension at different solid concentrations.On other hand,we conducted a detailed analysis of the solid distribution dependency on the impeller rotational speed at different solid volume fraction,which allows a good understanding of the parameters controlling the homogenization in the desupersaturator. 展开更多
关键词 CFD Multiphase flow Mass transfer phosphoric acid AGITATION
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