The objective of this study is to examine the solubilization effects of polycyclic aromatic hydrocarbons (PAHs) using various surfactants. Naphthalene was chosen to represent PAH compounds and anionic sodium dodecyl sulfate (SDS) surfactant and nonionic polyoxyethylene surfactants (C10E4、C10E8 and C14E8) were employed. A series of batch experiments in an absorption cell were performed at 50℃ and surfactant concentration both lower and higher than the critical micelle concentration (CMC). Naphthalene was analyzed by solid-phase microextraction equipment (SPME) and gas chromatograph (GC) with a photon ionization detector (PID). The CMC values of SDS were measured by a conductivity meter. Experimental results show that CMC values increased with temperature and decreased with pH values because of the electrolyte effects. Lower than critical micelle concentration (CMC), the apparent solubility and absorption rates of naphthalene with or without CO2 or SO2 were practically identical to those of pure water. However, higher than CMC, equilibrium naphthalene apparent solubility increased linearly in proportion to the surfactant concentrations. Naphthalene apparent solubility slightly increased with pH. The apparent solubility of naphthalene, CO2, and SO2 all decreased owing to competitive absorption in a simultaneous absorption system. The major absorption mechanism of naphthalene is the solubilization in the core of micelles, however, CO2 or SO2 was likely to be adsorbed at the surface of hydrophilic regions of micelles.

Greenhouse gas,Surfactant,Removal rate