Bioflocculant Synthesized by Klebsiella pneumoniae during 1,3-Propanediol and Bio-diesel Integration Process

The bio-diesel and 1,3-prpanediol ( 1,3-PD) processes are combined in our practices. The properties of flocculant from 1,3-propanediol fermentation was investigated. The characterization of the bioflocculant by GPC indicated the average molecular weight was about 2.0x10(5) Da. The neutral mono saccharides were the main component of the flocculant. Ca2+, Mg2+, Cu2+, K+ and Na+ were employed as flocculant aid to investigate the flocculating activity with Kaolin suspension. Ca2+ and Mg2+ provided the significant positive effect whereas Cu2+ provided a negative effect. 3.4 mmol/l Ca2+ was chosen for the further research. Two peaks of flocculating activity appeared at about pH 4.5 and 10, respectively. A case study of dye removal showed that the by-product flocculant from of 1,3-PD fermentation was a promising material for discoloring of textile wastewater.