surfactants; adsorption; subbituminous coal; zeta potential

The work deals with the parallel monitoring of adsorption and changes in zeta potential. A sample of natural subbituminous coal was selected as the adsorption material. The changes in the zeta potential values were then used to calculate the amount adsorbed. To calculate the adsorbed amount, we used a modified Langmuir equation, in which we replaced the adsorbed amount with zeta potential values. The results of the adsorbed amount calculated on the basis of the analytical determination of the equilibrium surfactant concentration were compared with the results calculated on the basis of the changes in the zeta potential. The difference between the theoretical and experimental value of the adsorbed amount was about 10% in the case of the highest initial surfactant concentration. The measurement of the zeta potential can be used to assess the quantity of the adsorption process. This approach is possible especially in the case of monolayer coating.

The work deals with the parallel monitoring of adsorption and changes in zeta potential. A sample of natural subbituminous coal was selected as the adsorption material. The changes in the zeta potential values were then used to calculate the amount adsorbed. To calculate the adsorbed amount, we used a modified Langmuir equation, in which we replaced the adsorbed amount with zeta potential values. The results of the adsorbed amount calculated on the basis of the analytical determination of the equilibrium surfactant concentration were compared with the results calculated on the basis of the changes in the zeta potential. The difference between the theoretical and experimental value of the adsorbed amount was about 10% in the case of the highest initial surfactant concentration. The measurement of the zeta potential can be used to assess the quantity of the adsorption process. This approach is possible especially in the case of monolayer coating.