The Removal of Hydrophobic Matter from Thermosensitive Poly[(ethylene glycol) Monomethyl Ether Acrylate] Gel Adsorbent in Alcohol-Water Mixtures.

A thermosensitive gel that exhibits lower critical solution temperature (LCST) becomes hydrophilic at low temperatures and hydrophobic at high temperatures in water. A system for absorbing hydrophobic organic matters that exploits this property has been reported. While washing the gel at a low temperature with a good solvent is a possible method for removing the adsorbed matter, a process that then shrinks the gel is also required.

Synthesis, Phase-Transition Behaviour, and Oil Adsorption Performance of Porous Poly((ethylene glycol) Alkyl Ether Acrylate) Gels.

To probe the effects of pendant side-chain structures on the properties of porous thermoresponsive polymer gels, (ethylene glycol) alkyl ether acrylates were polymerised in an aqueous medium under radical-mediated phase-separation conditions. The monomer structures varied according to the lengths and termini of their ethylene glycol side chains. The porous poly((ethylene glycol) alkyl ether acrylate) (POEGA) gels exhibited variable lower critical solution temperatures (LCSTs) but similar and rapid swelling-deswelling behaviours.

The effect of γ-FeOOH on enhancing arsenic adsorption from groundwater with DMAPAAQ + FeOOH gel composite.

Arsenic contamination of groundwater is a serious concern worldwide. The research gaps in removing arsenic are selectivity, regeneration and effective removal rate at neutral pH levels. In this study, we discussed the reasons of the high arsenic adsorption from groundwater of our previously developed adsorbent, a cationic polymer gel, N,N-dimethylamino propylacrylamide, methyl chloride quaternary (DMAPAAQ), loaded with iron hydroxide.

Removal of Arsenic Using a Cationic Polymer Gel Impregnated with Iron Hydroxide.

In this work, we prepared an adsorbent composed of a cationic polymer gel containing iron hydroxide in its structure designed to adsorb arsenic from groundwater. The gel we selected was the N,N-dimethylamino propylacrylamide methyl chloride quaternary (DMAPAAQ) gel. The objective of our preparation method was to ensure the maximum content of iron hydroxide in the structure of the gel.

Deterioration Mechanism of a Tertiary Polyamide Reverse Osmosis Membrane by Hypochlorite.

A tertiary polyamide membrane was synthesized using ,'-dimethyl--phenylenediamine. The durability of this membrane to chlorination by hypochlorite treatment followed by sodium hydroxide treatment was examined, and then deterioration mechanisms were proposed. The tertiary polyamide membrane demonstrated better durability to free chlorine than a conventional secondary polyamide one; however, the former was deteriorated by hypochlorite for 24 h at 2000 ppm of free chlorine below pH 7.

Development and regeneration of composite of cationic gel and iron hydroxide for adsorbing arsenic from ground water.

Globally, arsenic contaminated groundwater is a serious concern for human health. Previous studies have developed various methods to remove arsenic. But, most of them fail to selectively adsorb arsenic and regenerate.