Solvent extraction experiments of La(III) with di-(2-ethylhexyl)phosphoric acid (P204) from chloride solution in the presence of a complexing agent (lactic acid) have been performed. The effective separation factors c...Solvent extraction experiments of La(III) with di-(2-ethylhexyl)phosphoric acid (P204) from chloride solution in the presence of a complexing agent (lactic acid) have been performed. The effective separation factors can be achieved when the complexing agent is added to the aqueous phase of the extraction system. The complexing agent lactic acid can be effectively recycled using tributyl phosphate (TBP) as extractant, by the use of a countercurrent extraction process, and the chemical oxygen demand (COD) value in the raffinate is 57.7 mg/L, which meets the emission standards of pollutants from rare earths industry. Thus, the simple and environment-friendly complexing method has been proved to be an effective strategy for separating light rare earths, and provides a positive influence on the purification of La(III).展开更多
Process reinforcement research was carried out in Y-junction slug flow microreactors under variable conditions,using EHEHPA(2-ethylhexyl phosphonic acid mono-2-ethylhexyl)to extract yttrium(Ⅲ)from hydrochloric acid s...Process reinforcement research was carried out in Y-junction slug flow microreactors under variable conditions,using EHEHPA(2-ethylhexyl phosphonic acid mono-2-ethylhexyl)to extract yttrium(Ⅲ)from hydrochloric acid solution.The influence of pH and flow rate on the extraction-reaction efficiency,slug size,mass transfer performance was assessed.The experimental results showed that maximum extraction-reaction efficiency of 91.85%can be achieved in the smallest microreactor(residence time is 11.25 s),which was significantly higher than traditional extraction requiring more than 10 min.The slug length tended to decrease with the increase of pH and flow rate.Volumetric mass transfer coefficients for the slug flow microreactors were found to be in the range of 1.39×10^-1-1.642s^-1 that is several orders of magnitude higher as compared to traditional extractors,which testified the beneficial effects of Y-junction slug flow microreactor.Significant mass transfer reinforcement has prompted the use of microreactor as a suitable alternative to traditional extractors,which can advantageously improve the economic and environmental development of mineral processing.展开更多
文摘Solvent extraction experiments of La(III) with di-(2-ethylhexyl)phosphoric acid (P204) from chloride solution in the presence of a complexing agent (lactic acid) have been performed. The effective separation factors can be achieved when the complexing agent is added to the aqueous phase of the extraction system. The complexing agent lactic acid can be effectively recycled using tributyl phosphate (TBP) as extractant, by the use of a countercurrent extraction process, and the chemical oxygen demand (COD) value in the raffinate is 57.7 mg/L, which meets the emission standards of pollutants from rare earths industry. Thus, the simple and environment-friendly complexing method has been proved to be an effective strategy for separating light rare earths, and provides a positive influence on the purification of La(III).
基金support from the following program:Yunan Ten Thousand Talents Plan Young&Elite Tal-ents Project(No.YNWR-QNBJ-2018-323).
文摘Process reinforcement research was carried out in Y-junction slug flow microreactors under variable conditions,using EHEHPA(2-ethylhexyl phosphonic acid mono-2-ethylhexyl)to extract yttrium(Ⅲ)from hydrochloric acid solution.The influence of pH and flow rate on the extraction-reaction efficiency,slug size,mass transfer performance was assessed.The experimental results showed that maximum extraction-reaction efficiency of 91.85%can be achieved in the smallest microreactor(residence time is 11.25 s),which was significantly higher than traditional extraction requiring more than 10 min.The slug length tended to decrease with the increase of pH and flow rate.Volumetric mass transfer coefficients for the slug flow microreactors were found to be in the range of 1.39×10^-1-1.642s^-1 that is several orders of magnitude higher as compared to traditional extractors,which testified the beneficial effects of Y-junction slug flow microreactor.Significant mass transfer reinforcement has prompted the use of microreactor as a suitable alternative to traditional extractors,which can advantageously improve the economic and environmental development of mineral processing.
