Flocculation characteristics of polyacrylamide grafted cellulose from Phyllostachys heterocycla: An efficient and eco-friendly flocculant

•A BPC-g-PAM flocculant is prepared based on the cellulose from Phyllostachys heterocycla.•The flocculation effect and mechanism of the novel BPC-g-PAM are investigated.•The resultant BPC-g-PAM flocculant is biodegradable and environment-friendly.•The BPC-g-PAM flocculant has excellent turbidity-removal capacity.•An effluent from paper mill was used to evaluate the flocculation of BPC-g-PAM.

This work presents a synthesis process and flocculation characteristics of an eco-friendly flocculant based on bamboo pulp cellulose (BPC) from Phyllostachys heterocycla. Ployacrylamide (PAM) was grafted onto the BPC by free-radical graft copolymerization in homogeneous aqueous solution. The optimal synthesis conditions of the bamboo pulp cellulose-graft-ployacrylamide flocculant (BPC-g-PAM) and its performance on wastewater treatments were investigated. A UV-based method was used to rapidly determine the degree of substitution (DS) of BPC. The results showed that, under the optimal synthesis conditions, the obtained BPC-g-PAM held a grafting ratio of 43.8% and DS of 1.31. Turbidity removal of the product reached 98.0% accompanying with the significant flocculation and sedimentation in target suspensions. The flocculation mechanism was explored by means of zeta potential method. For negatively charged contaminants, like kaolin clay particles, the BPC-g-PAM could remove the contaminants efficiently via bridging and charge neutralization in acidic or neutral environment.

Graphical abstractProposed synthesis process and potential flocculation mechanism of the BPC-g-PAM product.Figure optionsDownload full-size imageDownload high-quality image (216 K)Download as PowerPoint slide