Zn induced surface modification of stable goethite nanoparticles for improved regenerative phosphate adsorption

Iron oxide-based adsorbents showed potential to reach ultra-low phosphorus (P) concentrations to prevent eutrophication and recover P. High affinity, high capacity at low P concentrations (<1 mg L⁻¹), good stability, and reusability of the adsorbent are key factors for economic viability. In this study, nanoparticles of goethite...

Effect of goethite doping using elements with different preferential oxidation states for improved reversible phosphate adsorption

Phosphorus (P) removal from freshwater bodies to ultra-low concentrations is fundamental to prevent eutrophication, while its recovery is necessary to close the P usage cycle. Iron oxide-based adsorbents seem promising candidates, being abundant, cheap, and easy to synthesize compounds, with good affinity for P. Affinity is the key parameter...

FeOOH and (Fe,Zn)OOH hybrid anion exchange adsorbents for phosphate recovery: A determination of Fe-phases and adsorption–desorption mechanisms

Hybrid anion exchange adsorbents (HAIX) seem promising to prevent eutrophication and recover phosphate (P). HAIX consist of an anion exchange resin (AIX) backbone, promoting anion physisorption (outer-sphere complex), impregnated with iron (hydr)oxide nanoparticles (NPs), for selective P chemisorption (inner-sphere complex). In this work, for...

Adsorption as a technology to achieve ultra-low concentrations of phosphate: Research gaps and economic analysis

Eutrophication and the resulting formation of harmful algal blooms (HAB) causes huge economic and environmental damages. Phosphorus (P) from sewage effluent and agricultural run-off has been identified as a major cause for eutrophication. Phosphorous concentrations greater than 100 μg P/L are usually considered high enough to cause...

Effect of pore size distribution and particle size of porous metal oxides on phosphate adsorption capacity and kinetics

Phosphate is a vital nutrient but its presence in surface waters even at very low concentrations can lead to eutrophication. Adsorption is often suggested as a step for reducing phosphate down to very low concentrations. Porous metal oxides can be used as granular adsorbents that have a high surface area and hence a high adsorption capacity....

Understanding and improving the reusability of phosphate adsorbents for wastewater effluent polishing

Phosphate is a vital nutrient for life but its discharge from wastewater effluents can lead to eutrophication. Adsorption can be used as effluent polishing step to reduce phosphate to very low concentrations. Adsorbent reusability is an important parameter to make the adsorption process economically feasible. This implies that the adsorbent...

Effect of pore size distribution on iron oxide coated granular activated carbons for phosphate adsorption – Importance of mesopores

Adsorption is often suggested for to reach very low phosphate levels in municipal wastewater effluent and even to recover phosphate. Adsorbent performance is usually associated with surface area but the exact role of the pore size distribution (PSD) is unclear. Here, we show the effect of the PSD on phosphate adsorption. Granular activated...