Effects of organic acids of different molecular size on phosphate removal by HZO-201 nanocomposite

Abstract

Various organic acids in wastewater effluent could significantly influence the performance of phosphate adsorbent. This study focused on the effects of organic acids of different-molecular-size on phosphate adsorption by a novel nanocomposite HZO-201. Three organic acids (gallic acid (GA), tannic acid (TA) and humic acid (HA)) with distinct molecular size (HA > TA > GA) were chosen for this purpose. Both isotherm and kinetic tests of phosphate adsorption were conducted in the single-phosphate and binary system, and a series of microscopic techniques (i.e., XPS, FT-IR and SEM-EDX) and N adsorption-desorption test were employed to explore the underlying mechanism. It was found that GA could greatly weaken phosphate adsorption capability of HZO-201 by directly competing for ammonium group on the nanocomposite, TA exhibited significant inhibition on phosphate adsorption rate mainly through pore constriction/blockage, while HA posed negligible impact on phosphate adsorption because of the size exclusion effect. It was also observed that although GA, TA and HA showed substantial influence on bulky HZO due to complexation, their impact on the nano-HZO loaded inside HZO-201 was little. The covalently bounded ammonium group and the networking pore structure of HZO-201 may play important roles in it.

Removal of Glyphosate from Aqueous Solution Using Nanosized Copper Hydroxide Modified Resin: Equilibrium Isotherms and Kinetics

“…Macroporous exchange resin such as D201 have been regarded as an excellent adsorbent to remove numerous organic pollutants due to their preferred pore structure, stable framework, and great adsorption capacity. , Nevertheless, resins are not suitable for the removal of glyphosate when plenty of inorganic salts existing owing to low salinity resistance. It is well-known that nanosized copper hydroxides has high specific surface areas and lattice defects.…”

Efficient Removal of Trace Se(VI) by Millimeter-Sized Nanocomposite of Zerovalent Iron Confined in Polymeric Anion Exchanger

“…Typically, HA is negatively charged, and its adsorption onto the corrosion products on the ZVI surface might be responsible for the slight inhibitory effect. , On the other side, HA could form complexes with soluble Fe species. , The formed complexes of large molecules and steric structures might hinder the mass transfer of Se­(VI) and block some reactive sites. Nevertheless, in this study, the favorable performance might be attributed to the size exclusion effect, and the nanoporous structure of nZVI@D201 is supposed to hinder HA permeation inside the polymeric phase and interaction with the embedded ZVI nanoparticles …”

Nanoscale Lanthanum Carbonate Hybridized with Polyacrylic Resin for Enhanced Phosphate Removal from Secondary Effluent

“…Organic acids, which were preferentially adsorbed by IERs, could be averse to the separation of phosphate from water. , Thus, three different organic acids [HA, tannic acid (TA), and gallic acid (GA)], which accounted for 14–60% (in mass) of the organic material in WWTP bioeffluents, were chosen as the interferential substances . To investigate the effects of the supporting resins on phosphate removal, NLC@213 and NLC@201 were employed to conduct the adsorption experiments under the disturbance of organic acids.…”