Development and improvment of analytical methods for speciation scheme of Al in the mobile soil phase.

A new method of isotachophoresis was developed allowing the determination of environmentally relevant concentrations of free aluminium-ions (greater or equal than 0,05 mg/l) in soil solutions. It is a particular advantage of the method that the originality of the samples is maintained. The specification of the method was tested by determining the formation constant of a weak Al complex, and the first hydrolysis equilibrium. Additionally, photometric and ion exchange methods were tested for the determination of Al species. On the basis of combined application of these method a speciation scheme of Al compounds in the mobile soil phase was developed. The feasibility of the analysis scheme was checked by means of lysimter experiments.