Summary: | Colloidal gels are possible intermediates in the generation of highly porous particle systems. In the production process the gels are fragmented after their formation. These gel fragments compact to particles whose application-technological properties are determined by their size and porosity. In the case of precipitated silica gels, this consolidation process depends on temperature and pH, among other parameters. It is shown that these dependencies can be characterized by oedometer measurements. Originally, the oedometer test (one-dimensional compression test) stemmed from soil mechanics. It has proven to be an interesting novel examination method for gels. Quantitative data of the time-dependent shrinkage of gel samples can be obtained. The consolidation of the gels shows a characteristic dependence on the above parameters.
|