Solubility enhancement of producer gas tar compounds in water using sodium dodecyl sulfate as a surfactant

• Solubility enhancement of tar compounds using SDS in water was studied.
• SDS significantly improved aqueous solubility of tar compounds.
• Solubility of tar compounds correlated linearly with SDS concentration.
• Solubility of tar compounds reduced as the solvent temperature increased.

The overall goal of this study was to improve the solubility of tar compounds in water using a surfactant, sodium dodecyl sulfate (SDS). The solubility experiments were performed using 100-ml media bottles. Benzene, toluene, ethylbenzene, styrene, and p-xylene were used as model tar compounds because these compounds are sparingly soluble in water. The solubility of tar compounds was measured using UV/VIS spectrophotometer. Statistical analysis showed that solubilities of tar compounds improved significantly (p < 0.0001) using SDS above the critical micelle concentration. Experimental results showed that the solubility of benzene, toluene, ethylbenzene, styrene and p-xylene increased 4 to 14, 9 to 33, 19 to 69, 18 to 83 and 29 to 135 fold, respectively, as SDS concentration increased from 0, i.e., water as control to 15, 30, 45 and 60 g/L at solvent temperature of 20 °C. Results also showed that solubilities of benzene, toluene and ethylbenzene decreased as the solvent temperature increased.