Application of << mass titration >> to determination of surface charge of metal oxides

The mass titration method, used for the point of zero charge determination, was extended to the measurement of the surface charge density. The results agree with the common method, which is the acid-base titration of the coll oidal suspension. The advantage of mass titration is that one does not need to perform blank titration, instead one simply adds metal oxide powder to the electrolyte aqueous solution of known pH. To cover the pH range above a nd below the point of zero charge, two experimental runs are necessary.