Effects of surface structure on the filtration properties of microcrystalline cellulose

The filtration of biomaterials is often a challenge due to high filtration resistances and the formation of compressible filter cakes. This study investigates how the local filtration properties of microcrystalline cellulose, a biomaterial forming compressible filter cakes, are affected by the surface structure of its particles. The surface structure was modified through mechanical shearing and the treatment resulted in an increased surface ruggedness along with a small decrease in particle size distribution. The mechanical treatment was found to increase the local specific filtration resistance to a large extent whereas no significant change to the local filter cake solidosity was observed. The relationship between the local solidosity of the filter cake and the local specific filtration resistance could be described by a cell model as flow around porous spheres with negligible permeability. The effect of an increased surface ruggedness was represented in this model as an increased specific surface area subjected to drag as well as a decrease in particle solidosity. (C) 2014 Elsevier B.V. All rights reserved.