| 摘 要： | This study addresses the liquid–liquid extraction behavior of phosphorus from a sulfuric acid solution using benzyl dimethyl amine(BDMA) in kerosene. The extraction equilibria investigated with varied BDMA concentrations could reveal the formation of■ complex in the organic phase. The thermodynamic properties determined at various temperatures indicated that the process was exothermic with a calculated enthalpy(■) of-24.0 k J·mol~(-1). The organic-to-aqueous phase(O/A) volume ratio was varied to elucidate the quantitative extraction of phosphorus. The Mc Cabe–Thiele diagram plotted for the extraction isotherm was validated for the requirement of three counter-current stages in the extraction at an O/A volume ratio of 2.0/3.5. The back-extraction of phosphorus from the loaded organic phase was quantitatively achieved by contacting 4.0 mol·L~(-1) H_2SO_4 solution in three stages of counter-current contact at an O/A volume ratio of 3/2. This study can be applied to remove phosphorus from the sulfuric acid leach solutions of monazite processing, and many other solutions.
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