SYNTHESIS AND MODELING OF AGGLOMERATION AND DISINTEGRATION PROCESS OF OXIDE AND NOBLE NANOPARTICLES FOR SOLVING POPULATION BALANCES IN PRECIPITATION

摘要

Agglomeration and disintegration of oxide nanoscaled particles is a challenge to be met when controlling particle size distributions in many areas like precipitation, crystallization and milling. The presented work shows a combined experimental as well as numerical approach to determine particle size distribution using titanium dioxide as the model substance. Modeling must now include the influence of colloidal surface forces and hydrodynamic forces on particle aggregation and breakup. The superposition of the population balance models for agglomeration and grinding with the appropriate kernels leads to a system of partial differential equations, which can be solved in various ways numerically solved by different methods. This includes a comparison of the derived particle size distributions, moments and its accuracy depending on the starting particle size distribution and the used agglomeration and disintegration kernels. Finally, the computational effort of both methods in comparison to the prior mentioned parameters is evaluated in terms of practical application.