Mixed Matrix PVDF Membranes With in Situ Synthesized PAMAM Dendrimer-Like Particles: A New Class of Sorbents for Cu(II) Recovery from Aqueous Solutions by Ultrafiltration

Abstract

Advances in industrial ecology, desalination, and resource recovery have established that industrial wastewater, seawater, and brines are important and largely untapped sources of critical metals and elements. A Grand Challenge in metal recovery from industrial wastewater is to design and synthesize high capacity, recyclable and robust chelating ligands with tunable metal ion selectivity that can be efficiently processed into low-energy separation materials and modules. In our efforts to develop high capacity chelating membranes for metal recovery from impaired water, we report a one-pot method for the preparation of a new family of mixed matrix polyvinylidene fluoride (PVDF) membranes with in situ synthesized poly­(amidoamine) [PAMAM] particles. The key feature of our new membrane preparation method is the in situ synthesis of PAMAM dendrimer-like particles in the dope solutions prior to membrane casting using low-generation dendrimers (G0 and G1-NH2) with terminal primary amine groups as precursors and epichlorohydrin (ECH) as cross-linker. By using a combined thermally induced phase separation (TIPS) and nonsolvent induced phase separation (NIPS) casting process, we successfully prepared a new family of asymmetric PVDF ultrafiltration membranes with (i) neutral and hydrophilic surface layers of average pore diameters of 22–45 nm, (ii) high loadings (∼48 wt %) of dendrimer-like PAMAM particles with average diameters of ∼1.3–2.4 μm, and (iii) matrices with sponge-like microstructures characteristics of membranes with strong mechanical integrity. Preliminary experiments show that these new mixed matrix PVDF membranes can serve as high capacity sorbents for Cu­(II) recovery from aqueous solutions by ultrafiltration.

Copper Ions Removal from Water using A2B3 Type Hyperbranched Poly(amidoamine) Hydrogel Particles

“…In recent decades, copper has becomes one of the popular technology metals in the industrial field. It is widely used from electrical wires to integrated circuits and thin-film solar cells [6], but copper ions show toxicity to humans, living organisms, and the environment [7]. From this point of view, the removal of the heavy metal ions that are poisoning the aqueous environment is an issue which needs a continuous research effort, in addition to the restriction of the use of toxic heavy metals.…”

Preparation of PVDF/Hyperbranched-Nano-Palygorskite Composite Membrane for Efficient Removal of Heavy Metal Ions

“…The ATR-FTIR spectra of the PVDF membrane and PVDF/PAMAM-Pal membrane are compared in curves a–e in Figure 5. The characteristic FTIR bands of PVDF membrane still existed for PVDF/PAMAM-Pal membranes, which suggested that the structure of PVDF was not destroyed [40]. In addition, PVDF/PAMAM-Pal membranes had new absorption bands at 1650 cm −1 and 1545 cm −1 due to bending vibrations of N–C=O bonds (amide II) and stretching vibrations of C–N groups [30].…”

A Review: Adsorption and Removal of Heavy Metals Based on Polyamide-amines Composites

“…The desorption experiments showed that PVDF-g-PAA-PAMAM membranes had excellent recycling performance. Kotte et al (2015) prepared a novel mixed matrix polyvinylidene fluoride (PVDF) composites membrane via one-pot method, which contained in situ synthesized polyamide-amines (PAMAMs) particles, and investigated its adsorption performance for Cu(II). The present experiment shows that the mixed matrix PVDF membranes can act as a novel high-capacity adsorbent to recover Cu(II) from aqueous solution.…”