Supramolecular fabrication of hyperbranched polyethyleneimine toward nanofiltration membrane for efficient wastewater purification

Abstract

Nanofiltration technology has opened an efficient pathway to addressing the grand issue of wastewater purification. Polyethyleneimine (PEI), as a hydrophilic polymer, is a promising material to manufacture separation membranes owing to its superiority. Here, we prepared a hyperbranched PEI-based separation membrane through the supramolecular hydrogen bond interaction for wastewater purification. The amino groups in the PEI molecule were partially oxidized to the nitro groups with sodium hypochlorite (NaClO). Moreover, the PEI molecular chains can be regulated from the hyperbranched state to the internal nucleation state. Molecular dynamics simulation results further indicated the strong hydrogen bonds among the oxidized PEI (O-PEI) molecular chains and the decreased gyration radius of the O-PEI molecule due to the formation of the nitro groups. In addition, the wettability and zeta potential of O-PEI membranes can be controlled by adjusting the molecular weight and oxidation degree of the PEI molecules. Under the collective effect of size screening and charge repulsion, the O-PEI separation membrane displayed a wide range of purification capabilities for contaminations, such as dye molecules and salts. This work may offer a new strategy to fabricate hyperbranched O-PEI membranes for wastewater purification.

Advancing Strategies of Biofouling Control in Water-Treated Polymeric Membranes

“…Therefore, improving the hydrophilicity of the membrane surface can not only effectively reduce the adhesion of microorganisms and other contaminants, but also increase the permeating flux of the membrane. The highly hydrophilic polymers, such as polyethylene glycol (PEG)ylated materials, polyethylenimine (PEI), sericin (a natural polymer), hyperbranched poly(amido amine) (PAMAM), polydopamine, amino acids, and polyamide, have been commonly employed to combat nonspecific protein adsorption and cell adhesion due to their extremely low fouling ability [ 70 , 71 , 72 , 73 ].…”

Efficient degradation of Health-threatening organic pollutants in water by atomically dispersed Cobalt-Activated peroxymonosulfate

“…[3][4][5] Many approaches have been developed to remove HTOPs from water or soil, such as physical adsorption, chemical adsorption, photocatalytic degradation, electrocatalysis degradation, and advanced oxidation process (AOPs) degradation. [6][7][8][9][10][11][12] Adsorption has the advantage of simple operation; however, slow adsorption kinetics and the high cost of post-treatment of adsorbent sludge lead to this method requiring a high investment. [13,14] Photocatalytic or electrocatalysis degradation is environmentally friendly but require complicated equipment, additional light and electric energy input, and suitable catalysts.…”

Nature-Inspired Polyethylenimine-Modified Calcium Alginate Blended Waterborne Polyurethane Graded Functional Materials for Multiple Water Purification

“…It is known that sodium alginate (SA) can form a superhydrophilic skeleton through simple chemical cross-linking, endowing it with an oil-stain repelling property. , In addition, the abundant carboxyl and hydroxyl groups are easy to graft and can adsorb heavy metal ions through ion-exchange and complexation. − Branched polyethylenimine (PEI) is a positively charged water-soluble polymer containing many amino groups, which can be connected with alginate through amide reaction. Moreover, the abundant amino groups in PEI can be used to remove heavy metal ions, sterilize, and adsorb micro/nano plastics. − Green, environmentally friendly, and non-volatile waterborne polyurethane (WPU) can be used as a filler for gel materials to improve flexibility and three-dimensionality. , The above three materials are combined to form a powerful SA@WPU@WPU functional layer to effectively remove complex pollutants such as heavy metal, bacterium, micro-oil droplets, and nanoscale plastics.…”