Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various det...Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various determination methods. The effects of leaching time,leaching temperature,leaching agent concentration,leaching L/S ratio,granularity of material,additive consumption were investigated based on the mineralogy.The results show that under the conditions of leaching time of 3-4 h, temperature of 150℃,sulfuric acid consumption of 25%?30%,ratio of liquid to solid of 1.2:1,the granularity less than 0.074 mm, additive consumption of 3%-5%,and oxygen pressure of 1.2 MPa,and the vanadium leaching rate can be more than 92%by the method of two-step pressurized acid leaching.The powdery V2O5 product with 99.52%in V2O5 content is obtained by the flowsheet of acid recovery,removing iron by reduction process,solvent extraction,precipitating vanadium with ammonium water,and pyrolysis from the stone-coal oxygen pressure acid-leaching solution.The total recovery efficiency of vanadium is above 85%,which is more than 20%higher than that obtained in the conventional process.Furthermore,the new process does not cause air pollution since no HCl or Cl2 is released by calcination of the raw material.展开更多
This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the peri...This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the periodic flow processes for industrial applications. In this regard, a comprehensive evaluation on the energy consumption in case of a pulsed flow for three different chemical systems is conducted and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and the plate free area is investigated as well. Moreover, the concept of characteristic velocity models at flooding points is evaluated with respect to the variation of pressure drop along the column at different operational conditions.展开更多
优化了中药葛根异黄酮类成分加压溶剂提取的条件。采用高效液相色谱法同时测定葛根提取液中葛根素、大豆苷和大豆苷元含量,以三者含量总和为评价指标,以用正交设计的考察方式对影响加压溶剂提取葛根异黄酮类成分的因数进行优化。优选出...优化了中药葛根异黄酮类成分加压溶剂提取的条件。采用高效液相色谱法同时测定葛根提取液中葛根素、大豆苷和大豆苷元含量,以三者含量总和为评价指标,以用正交设计的考察方式对影响加压溶剂提取葛根异黄酮类成分的因数进行优化。优选出最佳提取条件:溶剂为甲醇;温度140℃;提取时间10 m in;压力8.27 MPa,置换体积为60%,并与葛根药典提取方法进行比较,结果表明:加压溶剂提取法具有提取时间短、溶剂消耗少、提取效率高、重现性好、操作模式多样化以及操作过程自动化等优点,将有助于中药质量控制提取过程的标准化。展开更多
建立了高效液相色谱串联质谱技术(Liquid chromatography tandem mass spectrometry,LC-MS/MS)同时测定土壤中邻苯二甲酸酯(Phthalic acid esters,PAEs)的分析方法。确定了土壤样品加速溶剂萃取最优条件是以正己烷为萃取溶剂,在160...建立了高效液相色谱串联质谱技术(Liquid chromatography tandem mass spectrometry,LC-MS/MS)同时测定土壤中邻苯二甲酸酯(Phthalic acid esters,PAEs)的分析方法。确定了土壤样品加速溶剂萃取最优条件是以正己烷为萃取溶剂,在160℃下,静态萃取4次,每次12 min,萃取液经旋转蒸发浓缩,以乙腈-0.1%甲酸溶液为流动相梯度洗脱分离后,用LC-MS/MS结合大气压化学源(Atmospheric pressure chemical ionization,APCI)进行定性及定量分析。土壤中11种PAEs的浓度与其峰面积呈良好的线性关系,检出限为0.03-13.0μg/kg,样品的加标平均回收率为72.8%-101.8%,相对标准偏差(RSD)为1.7%-6.7%。方法简便快速,且灵敏度高,适用于土壤中11种邻苯二甲酸酯的同时测定。展开更多
基金Project(2006AA06Z130)supported by the High-tech Research and Development Program of ChinaProject(50874053)supported by the National Natural Science Foundation of ChinaProject(2007GA010)supported by Science and Technology Bureau of Yunnan Province,China
文摘Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various determination methods. The effects of leaching time,leaching temperature,leaching agent concentration,leaching L/S ratio,granularity of material,additive consumption were investigated based on the mineralogy.The results show that under the conditions of leaching time of 3-4 h, temperature of 150℃,sulfuric acid consumption of 25%?30%,ratio of liquid to solid of 1.2:1,the granularity less than 0.074 mm, additive consumption of 3%-5%,and oxygen pressure of 1.2 MPa,and the vanadium leaching rate can be more than 92%by the method of two-step pressurized acid leaching.The powdery V2O5 product with 99.52%in V2O5 content is obtained by the flowsheet of acid recovery,removing iron by reduction process,solvent extraction,precipitating vanadium with ammonium water,and pyrolysis from the stone-coal oxygen pressure acid-leaching solution.The total recovery efficiency of vanadium is above 85%,which is more than 20%higher than that obtained in the conventional process.Furthermore,the new process does not cause air pollution since no HCl or Cl2 is released by calcination of the raw material.
基金School of Chemical Engineering, College of Engineering, University of Tehran, for the financial support
文摘This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the periodic flow processes for industrial applications. In this regard, a comprehensive evaluation on the energy consumption in case of a pulsed flow for three different chemical systems is conducted and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and the plate free area is investigated as well. Moreover, the concept of characteristic velocity models at flooding points is evaluated with respect to the variation of pressure drop along the column at different operational conditions.
文摘优化了中药葛根异黄酮类成分加压溶剂提取的条件。采用高效液相色谱法同时测定葛根提取液中葛根素、大豆苷和大豆苷元含量,以三者含量总和为评价指标,以用正交设计的考察方式对影响加压溶剂提取葛根异黄酮类成分的因数进行优化。优选出最佳提取条件:溶剂为甲醇;温度140℃;提取时间10 m in;压力8.27 MPa,置换体积为60%,并与葛根药典提取方法进行比较,结果表明:加压溶剂提取法具有提取时间短、溶剂消耗少、提取效率高、重现性好、操作模式多样化以及操作过程自动化等优点,将有助于中药质量控制提取过程的标准化。
文摘建立了高效液相色谱串联质谱技术(Liquid chromatography tandem mass spectrometry,LC-MS/MS)同时测定土壤中邻苯二甲酸酯(Phthalic acid esters,PAEs)的分析方法。确定了土壤样品加速溶剂萃取最优条件是以正己烷为萃取溶剂,在160℃下,静态萃取4次,每次12 min,萃取液经旋转蒸发浓缩,以乙腈-0.1%甲酸溶液为流动相梯度洗脱分离后,用LC-MS/MS结合大气压化学源(Atmospheric pressure chemical ionization,APCI)进行定性及定量分析。土壤中11种PAEs的浓度与其峰面积呈良好的线性关系,检出限为0.03-13.0μg/kg,样品的加标平均回收率为72.8%-101.8%,相对标准偏差(RSD)为1.7%-6.7%。方法简便快速,且灵敏度高,适用于土壤中11种邻苯二甲酸酯的同时测定。