Effect of straight-chain alcohols on the physicochemical properties of calcium lignosulfonate.

Lignosulfonate is an anionic surfactant from pulp processing industries. Alcohols are often used as cosurfactants in the application of surfactant. The improvement of straight-chain alcohols with different alkyl chain lengths as cosurfactant on the physicochemical properties of calcium lignosulfonate (CL) aqueous solution has been investigated. The results indicate that small amounts of straight-chain alcohols with longer alkyl chains are helpful in improving the surface activity of CL, especially when the number of carbon atoms in alcohols is 10 or larger. The adsorption amount of CL solutions with additives of longer chain alcohols on TiO(2) particles increases greatly, and the zeta potential of TiO(2) particles adsorbing CL rises significantly. It can be concluded that there is a cooperative effect of the longer chain alcohols on lignosulfonate to form a tighter adsorption layer at the interface. The steric hindrance increases with the increasing amount of adsorption, and the static repulsive force increases with the increasing zeta potential. Therefore, the effect of CL on the stability of the TiO(2) suspension is enhanced dramatically by addition of longer chain alcohols. This understanding can lead to further development in expanding the functionalities of the lignosulfonate through manipulation of the adsorption capacity of CL on solid particles and enhance the dispersive ability of CL on solid suspensions by adding longer straight-chain alcohols.