A novel biofilm photobioreactor using light guide plate enhances the hydrogen production

A novel biofilm photobioreactor (BPBR) using light guide plate (LGP) as light guider and biofilm support material was proposed to improve the hydrogen production. To further improve the biocompatibility and roughness of LGP surface, it was modified with SiO2-chitosan-medium (SCM) biomaterial. The luminous intensity on the surface of LGP and SCM-LGP were 10.1 W/m2 and 7.8 W/m2, respectively, much higher than that (2.8 W/m2) of the traditional polymethyl methacrylate (PMMA) flat-plate. The hydrogen production rate (HPR) of the BPBRs using LGP and SCM-LGP were 8.9 mmol/h/m2 and 11.6 mmol/h/m2, which were 0.62 and 1.11 times higher than that of the traditional BPBR using PMMA, respectively. In addition, the biofilm analysis including SEM and dry biofilm density showed that SCM-LGP was more suitable for the formation of biofilms relative to LGP and PMMA. These results suggested that the proposed BPBRs have great potential for immobilized cell technologies and biohydrogen production.