Cationic Pullulan Derivatives Based Flocculants for Removal of Some Metal Oxides from Simulated Wastewater

Modified polysaccharides have been increasingly used as flocculants in wastewater treatment due to their non-toxicity, low price, biodegradability, etc. However, the pullulan derivatives are less used in wastewater purification processes. Therefore, this article presents some data regarding FeO and TiO2 particle removal from model suspensions by some pullulan derivatives with pendant quaternary ammonium salt groups, trimethylammonium propyl carbamate chloride (TMAP(x)-P). The influence of the polymer ionic content, dose, and initial solution concentration as well as of the dispersion pH and composition (metal oxide content, salts, and kaolin) on the separation efficacy were considered. UV-Vis spectroscopy measurements have shown a very good removal efficacy of TMAP(x)-P for the FeO particles (around 95% and more), irrespective of the polymer and suspension characteristics; a lower clarification of the TiO2 particles suspension (removal efficiency between 68% and 75%) was noticed. Both the zeta potential and the particle aggregates size measurements revealed the charge patch as the main mechanism which governs the metal oxide removal process. The surface morphology analysis/EDX data provided supplementary evidence regarding the separation process. A good removal efficiency (90%) of the pullulan derivatives/FeO flocs for the Bordeaux mixture particles from simulated wastewater was found.

Automated summary

Due to their non-toxicity, low price, and biodegradability, modified polysaccharides are increasingly used as flocculants in wastewater treatment. However, pullulan derivatives have been less utilized in wastewater purification processes. This article provides data on the removal of FeO and TiO2 particles from model suspensions using pullulan derivatives with pendant quaternary ammonium salt groups, trimethylammonium propyl carbamate chloride (TMAP(x)-P). The study evaluates the influence of various factors on the separation efficacy, including polymer ionic content, dose, initial solution concentration, dispersion pH and composition. UV-Vis spectroscopy measurements show a high removal efficacy of TMAP(x)-P for FeO particles (around 95% and more), while a lower clarification of TiO2 particles suspension is observed (removal efficiency between 68% and 75%). The zeta potential and particle aggregates size measurements indicate that the charge patch mechanism plays a crucial role in the metal oxide removal process. Surface morphology analysis/EDX data provide additional evidence regarding the separation process. The pullulan derivatives/FeO flocs exhibit good removal efficiency (90%) for Bordeaux mixture particles in simulated wastewater.