A technique for purifying wastewater with polymeric flocculantproduced from waste plastic

One of the most important treatment processes in surface water treatment is coagulation. Surface waters such asrivers and lakes contain suspended particles and turbidity. With the aid of coagulants, and by flocculation process,followed by sedimentation and filtration, these impurities can be removed from raw waters. Besides conventionalchemicals such as alum and ferric chloride, polymers such as sulfonated polystyrene are getting common. In thisstudy, we are interested in waste plastics; waste polystyrene-containing additives were converted into a polymericflocculant by chemical modification. Specifically, waste polystyrene consisting of white coffee cups was sulfonatedto produce a water-soluble polymer. The sulfonation was characterised by FTIR technique and the degree ofsulfonation was determined by titration. The polymer provides high purification of the supernatant after flocculatinga kaolin suspension. Moreover, the material provides a pure supernatant in the treatment of actual wastewatercomparable to conventional polymeric flocculants. A new reclamation technology to convert waste plastic into afunctional polymer is reported.