Abstract
The effect of coexisting salts for adsorption of nonionic surfactants on activated carbon in aqueous solution was investigated. Inorganic salts which reduced the cloud point of polyoxyethylene nonylphenyl ether (NP-10) increased the adsorption of NP-10 on activated carbon, while inorganic salts which raised the cloud point disturbed the adsorption. In the case of organic salts, the adsorption of NP-10 on activated carbon was disturbed because of the competing adsorption between NP-10 and organic salts. The amount of adsorption of NP-10 decreased with increasing the hydrophobicity of organic salts. Sodium sulfate, sodium perchlorate and sodium citrate aggregated NP-10 molecules. The aggregation was influenced by temperature. The amount of adsorption of NP-14 on activated carbon was unaffected by the changes of pH in the range of 2 to 12.
