For the development of lithium ion recovery process from seawater, a series of experimental researches were performed. Solvent extraction of lithium ion from aqueous solution using kerosene as solvent was proposed. Li...For the development of lithium ion recovery process from seawater, a series of experimental researches were performed. Solvent extraction of lithium ion from aqueous solution using kerosene as solvent was proposed. Lithium ion is effectively extracted by thenoyltrifluoroace- tone-trioctylphosphine oxide （TTA-TOPO） in kerosene within 80 min. Extraction efficiency is severely influenced by stoichiometric parameters. Among the stoichiometric parameters, volume ratio of aqueous （A） to extraction （E） solution is the most influential parameter. After extrac- tion, lithium ion could be easily stripped from the extraction solution by acidic solutions. Stripping efficiency decreases with pH of acidic solutions, and the kind of acid does not affect the stripping efficiency. Extraction efficiency main- tains at more than 93 % even when the extraction solution is recycled three times. 65 % of lithium ion can be extracted from seawater by this solvent extraction process when magnesium ion is precipitated by NHaOH prior to solvent extraction process. Other metallic ions in seawater decrease the extraction efficiency of lithium ion.展开更多
The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar co...The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).展开更多
以DBU/甲醇为开关溶剂,大豆油代替藻类油脂,在无水条件下通过条件实验确定了开关溶剂提取油脂、开关溶剂循环利用两个实验的较好条件。提取大豆油:VDBU/V甲醇:1∶1;V开关溶剂:21 m L;V大豆油:7 m L;通CO_2t:35 min;T:室温;CO_2连续鼓泡...以DBU/甲醇为开关溶剂,大豆油代替藻类油脂,在无水条件下通过条件实验确定了开关溶剂提取油脂、开关溶剂循环利用两个实验的较好条件。提取大豆油:VDBU/V甲醇:1∶1;V开关溶剂:21 m L;V大豆油:7 m L;通CO_2t:35 min;T:室温;CO_2连续鼓泡;转速:540 r/min。大豆油的收率91.43%。开关溶剂循环:加热温度:130℃;冷凝回流1.5 h;N2连续鼓泡;转速:540 r/min。由L9(33)正交试验得出各因素对反应的影响强弱顺序为:V开关溶剂/V大豆油>通CO_2的温度>VDBU/V甲醇。开关溶剂循环次数可达到6次以上。展开更多
基金financially supported by the Research Grant of Pukyong National University (2014)
文摘For the development of lithium ion recovery process from seawater, a series of experimental researches were performed. Solvent extraction of lithium ion from aqueous solution using kerosene as solvent was proposed. Lithium ion is effectively extracted by thenoyltrifluoroace- tone-trioctylphosphine oxide （TTA-TOPO） in kerosene within 80 min. Extraction efficiency is severely influenced by stoichiometric parameters. Among the stoichiometric parameters, volume ratio of aqueous （A） to extraction （E） solution is the most influential parameter. After extrac- tion, lithium ion could be easily stripped from the extraction solution by acidic solutions. Stripping efficiency decreases with pH of acidic solutions, and the kind of acid does not affect the stripping efficiency. Extraction efficiency main- tains at more than 93 % even when the extraction solution is recycled three times. 65 % of lithium ion can be extracted from seawater by this solvent extraction process when magnesium ion is precipitated by NHaOH prior to solvent extraction process. Other metallic ions in seawater decrease the extraction efficiency of lithium ion.
基金supported by the National Natural Science Foundation of China(22078281)。
文摘The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).
文摘以DBU/甲醇为开关溶剂,大豆油代替藻类油脂,在无水条件下通过条件实验确定了开关溶剂提取油脂、开关溶剂循环利用两个实验的较好条件。提取大豆油:VDBU/V甲醇:1∶1;V开关溶剂:21 m L;V大豆油:7 m L;通CO_2t:35 min;T:室温;CO_2连续鼓泡;转速:540 r/min。大豆油的收率91.43%。开关溶剂循环:加热温度:130℃;冷凝回流1.5 h;N2连续鼓泡;转速:540 r/min。由L9(33)正交试验得出各因素对反应的影响强弱顺序为:V开关溶剂/V大豆油>通CO_2的温度>VDBU/V甲醇。开关溶剂循环次数可达到6次以上。
