Solvent Extraction Of The Thermal Dynamics Of Reverse Micelles Nature Of The Extractant

Solvent extraction is an important analytic technology. It is mainly used in analysis and separation. The assembly of this technology is simple and the manipulation is easy. So it is easy to realize massive production. The thermodynamic and kinetic property of solvent extraction is an important aspect of solvent extraction and is mainly about the study of extraction equilibrium, reaction rate and thermokinetic parameters .The further study of thermokinetic property of solvent extraction will supply a theory basis for ion extraction system. In this paper, the solvent extraction of Ag+ Pb~2+ La~3+ with l-phenyl-3methyl-4-Benzoyl-pyrazolane-5 has been studied. The equilibrium constants and thermodynamic parameters have been obtained and the property of extractants has been studied by the microcalorimetric method.1.The chief contents and conclusions1.1 Study of extraction thermokinetic propertyIn this paper, the ions(Ag~+ Pb~2+ La~3+ )were extracted. Their equilibrium equations are :Ag~++HPMBP (O) = Ag(PMBP)+H+Pb~2++2HPMBP (O) = Pb (PMBP) 2+2H+La3++3HPMBP (O) = La (PMBP) 3+3H+The reaction rate constant, reaction rate equation and activation energy were obtained and △_rH_m~θ was calculated. The thermodynamic function △_rH_m~θ, △_rG_m~θ 和 △_rS_m~θ were measured by microcalorimetric method. The determined △_rH_m~θ was compared with the calculated results, and they are very similar.1.2 Study of extractant's propertIn this paper, saponification-salt of PMBP has been made first. And it is diluted by different organic solvent such as normal octane, decane, dodecane,tetradecane, Hexade-cane. The formation of the function of reversed micelle for PMBP saponification-salt in above different organic phase was studied by using microcalorimetric method.The critical micelle concentration(CMC);aggregation number(n),formation constant of micelle(Km) and the thermodynamic functions (ArHme, ArGme f P ArSm6) were calculated.The saponification-salt for P507 was made with the method mentioned above and obtained similar regularity, however, the organic solvents are altered to decane, dodecane, tetradecane, benzene, toluene and xylene.2.The main innovative points2.1 Microcalorimetric method is a new method to determine the reaction heat of solvent extraction process, and it is more simple, convenient and reliable.2.2 In the extraction organic phase, the aggregation number(n)is small, so the traditional method is not enough. In this paper, CMC was determined by Microcalorimetric method quickly and correctly. The determination of micelle's aggregation number(n) in extrantant organic phase provided many important information to understand the extractant's state in extraction system.