Phase separation phenomena and thermodynamics of octylphenol polyoxyethylene ether in micellar solutions: Effect of high concentration of inorganic salts and linear correlation
| Autor: | Ye Xi Zhang, Dan Ni Li, Xiao Feng Quan, Huan Tian, Jing Huang, Zhao Hua Ren, Zheng Bo Qian, Rui Sheng, Jun Ru Wang, Bei Bei Li |
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| Rok vydání: | 2021 |
| Předmět: |
chemistry.chemical_classification
Aqueous solution Chemistry General Chemical Engineering Extraction (chemistry) Inorganic chemistry Enthalpy Salt (chemistry) Ether 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Gibbs free energy chemistry.chemical_compound symbols.namesake Pulmonary surfactant Micellar solutions symbols 0210 nano-technology |
| Zdroj: | Journal of Industrial and Engineering Chemistry. 99:172-178 |
| ISSN: | 1226-086X |
| Popis: | The phase separation phenomena or cloud points (CP) behavior of nonionic octylphenol polyoxyethylene ether with oxyethylene glycol ether unit of 15 (OP-15) were investigated in aqueous micellar solutions containing high concentrations of inorganic salts including NaCl, KCl, MgCl2, CaCl2, BaCl2, AlCl3, FeCl3, Na2SO4 and Na2SiO3. The change in CP induced by salts and its mechanism are discussed theoretically. In aqueous solutions containing high concentration of salt, for the first time the linear relationship between CP and salt concentration is well established to characterize the depression of CP. Based on pseudo phase separation model, thermodynamic parameters are estimated and adopted to further describe the phase separation process and the interactions between OP-15 molecules or the OP-15/water interactions. Thermodynamic parameters including standard Gibbs energy change ( Δ G C P 0 ), enthalpy change ( Δ H C P 0 ) and entropy change ( Δ S C P 0 ) indicate that the additions of different salts result in the change in entropy-driven nonspontaneous process of phase separation. These data, which are from the compensation temperatures and the change of molar heat capacity, also prove that different ions induce the change in the interactions between surfactant molecules or the surfactant–water interaction and thus affect the depression of CP. These findings help with understanding the effect of inorganic salts, especially the high concentration of salt, on CP of nonionic surfactant and then broadening the application of nonionic surfactant based on CP such as the extraction of biomaterials in biological samples derived from animals or plants, etc. |
| Databáze: | OpenAIRE |
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