Diffusion of phenol through a biofilm grown on activated carbon particles in a draft‐tube three‐phase fluidized‐bed bioreactor

TLDR

The study investigated phenol diffusion through a biofilm on activated carbon particles. Biofilm was cultivated on activated carbon in a draft‑tube three‑phase fluidized‑bed bioreactor under fed‑batch operation. Phenol did not adsorb onto the biofilm, and its diffusion coefficient within the biofilm was only 13–39 % of that in water, decreasing further with higher biofilm density—a behavior that likely applies to biofilms on various surfaces.

Abstract

Abstract Diffusion of phenol through a biofilm attached to activated carbon particles was investigated. The biofilm was grown on activated carbon particles in a draft‐tube three‐phase fluidized‐bed bioreactor operating in a fed‐batch mode. It was found that phenol did not adsorb on the biofilm and that the diffusion coefficient of phenol within the biofilm varied from 13 to 39% of its corresponding value in water. The diffusion coefficient of phenol within the biofilm was reduced by increasing the biofilm density. An extensive literature review of diffusion of substrates through biofilms indicated that this conclusion could be extended to biofilms grown on flat surfaces, rotating cylinders, and even bioflocs.