Biomass base membrane with phenol hydroxy-amino group for ultraselective adsorption of radioactive Co(II) in trace concentration

Abstract

60Co is widely utilized in industries and can emit high gamma energy. The removal radioactive 60Co in trace concentration from wastewater is important for human health and environment protection. Here, we designed a biomass base membrane with phenol hydroxyl-amino group for ultraselective enriching of trace concentration of Co2+ from radioactive wastewater. This novel membrane adsorbent (PAM–PBWT), that is, the immobilized black wattle tannin (BWT) modified with polyethylenimine onto the polyamide microporous membrane (PAM), utilizes phenolic hydroxyl and amino group can form a coordinated coordination with Co2+, exhibiting high selectivity adsorption to Co2+ even in the presence of other ions. A maximal adsorption capacity (0.39 mmol g−1) was reached at pH 8.0 and 323 K. The continuous adsorption experiments showed that the PAM–PBWT can enrich the trace concentration of Co2+ (60 ng L−1) from radioactive wastewater in the presence of other coexisting ions (K+, Ca2+, Na+, Mg2+, Zn2+, Mn2+, Fe3+). Moreover, the processing capacity of three-layer PAM–PBWT for simulated 60Co-containing wastewater can reach 80 L m−2. Notably, PAM–PBWT can be easily regenerated with 0.1 M HNO3 without the loss of adsorption capacity. Our work might introduce a new strategy for realizing selectivity adsorption of trace concentration irradiation contaminants from radioactive wastewater.