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Cloud point extraction (CPE) processes with two silicone surfactants, Dow Corning DC-190 and DC-193, were studied as preconcentration and treatment for the water polluted by three trace polycyclic aromatic hydrocarbons (PAHs): anthracene, phenanthrene and pyrene. For all cases, the volumes of surfactant-rich phase ob-tained by two silicone surfactants were very small, i.e. a lower water content in the surfactant-rich phase was ob-tained. For example, less than 3% of the initial solution was obtained in a 1% (by mass) surfactant solution, which was much smaller than that of TX-114 in the same surfactant concentration. And TX-114 is known as a high com-pact surfactant-rich phase among most nonionic surfactants, thus the comparison showed that an excellent enrich-ment was ensured in the analysis application by the CPE process with the silicone surfactants, and the lower water content obtained in the surfactant-rich phase is also important in the large scale water treatment. The influences of additives and phase separation methodology on the recovery of PAHs were discussed. Comparing with DC-193, DC-190 has a lower cloud point and a higher recovery (near 100%) of all the three PAHs in same surfactant con-centration, which was required for application as a preconcentration process prior to HPLC system. However the DC-190 solution is hard to be phase separated only by heating, whereas DC-193 has a relative higher phase sepa-rating speed by heating, but a high cloud point (around 360K) limits its application. Due to the phase separation by heating is the only method of CPE suitable to the large scale water treatment, the mixtures of two silicone surfac-tants solutions were investigated in this study. A solution containing 1% of mixed DC-190 and DC-193 (in the ratio of 90︰10) removed anthracene, phenanthrene and pyrene near 100% with a relative low cloud point and quick phase separating speed.
Processed for preconcentration and treatment for the water polluted by three trace polycyclic aromatic hydrocarbons (PAHs): anthracene, phenanthrene and pyrene. For all cases, the volumes of surfactant-rich phase ob-tained by two silicone surfactants were very small, ie a lower water content in the surfactant-rich phase was ob-tained. For example, less than 3% of the initial solution was obtained in And TX-114 is known as a high com-pact surfactant-rich phase among most nonionic surfactants, thus the comparison showed that an excellent enrichment-ment was ensured in the analysis application by the CPE process with the silicone surfactants, and the lower water content obtained in the surfactant-rich phase is also important in the large scale water treatment. The influences of additives and phase separation methodology on the recovery of PAHs were discussed. Comparing with DC-193, DC-190 has a lower cloud point and a higher recovery (near 100%) of all the three PAHs in same surfactant con-centration, which was required for application as a preconcentration process prior to HPLC system. However the DC-190 solution is hard to be phase separated only by heating, but DC-193 has a relative higher phase sepa rating of by heating, but a high cloud point (around 360K) limits its application. Due to the phase separation by heating is the only method of CPE suitable to the large scale water treatment, the mixtures of two silicone surfac-tants solutions were investigated in this study. A solution containing 1% of mixed DC-190 and DC-193 (in the ratio of 90: 10) removed anthracene, phenanthrene and pyrene near 100% with a relative low cloud point and quick phase separating speed.