Rapid and Selective Recycling of Ag(I) from Wastewater Through an Allylrhodanine Functionalized Micro-Filtration Membrane

Membrane filtration is one of the most rapid and effective method to recycle noble metal in wastewater. However, the poor selectivity and stability of membrane are also need to be considered in a complex wastewater. In this work, a polyvinylidene fluoride (PVDF) with 3-allylrhodanine (3-AR) modified composite 3-AR/PVDF membrane was fabricated by non-solvent induced phase separation method. The parameters of prepared 3-AR/PVDF membranes were examined, including water flux, selectivity and rejection.. The effect of 3-AR hybridization on the cross-sectional morphology and hydrophilicity of PVDF membranes was also investigated. The retention of Ag + was mainly relied on the chemical bonding of C=S and C-S groups on 3-AR. 3-AR/PVDF-0.13 membrane exhibited excellent performance in adsorption (46.42 mg cm -2 ), water flux (196.04 L m -3 h -1 ), rejection (8.75 mg), and selectivity ( β > 10). Membrane thickness exhibits a linear relationship with water flux and interception ( R 2 > 0.94), which could be regulated by the thickness of membrane. Most important, the costs of membrane and operation were assessed during the long-term filtration, which is of significance for practical applications