Removal and Recovery of Phosphate from Water and Wastewater Using Metal-Loaded Agricultural Waste-Based Adsorbents: A Review

Abstract

There is a growing research interest in the development of adsorbents based on agricultural wastes (AWs) for the removal of phosphate from waste water sources, which otherwise can cause eutrophication. Nevertheless, due to the lack of active exposed surface sites, raw AWs-based adsorbents are usually inefficient for the adsorption of phosphate from aquatic environment. Consequently, modification of raw adsorbents has been frequently used to improve their phosphate adsorption capacity. Of the various methods of modification, this review paper focused on most widely used chemical modification method. It presents a critical and comprehensive review of the literature on the effectiveness of metal-loaded agricultural wastes (MLAWs)-based adsorbents in removing and recovering of phosphate from waste waters. Mechanisms and factors affecting phosphate adsorption as well as phosphate desorption and regeneration from MLAW adsorbents are critically evaluates. If phosphate from waste waters can be of economical value, regeneration may partly overcome the future shortage of global phosphate rock reserves. It is evident from the literature survey presented herein that MLAWs-based adsorbents exhibited as potential adsorbent for the removal/recovery of phosphate from waste waters. However, there still needs a refined practical utility of these adsorbents on a commercial scale, which may serve as the novel, cost effective and environmentally benign methods of modification.

Acid-treated pomegranate peel; An efficient biosorbent for the excision of hexavalent chromium from wastewater

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Recent Advances in Biomass-Based Waste Materials for the Removal of Chromium (VI) from Wastewater: A Review

“…Various methods, such as electro-dialysis, membrane technology, redox reaction followed by precipitation, ion exchange, and adsorption are applied to eliminate(VI) from the aquatic environment [13,14]. Requirements for the high energy and expensive instruments, lacking metal removal completion, toxic waste sludge, and disposals, etc., are the reasons which limit the use of most of the options mentioned above [15][16][17][18]. The adsorptive method of removal is the most widely used method for the removal of heavy metal pollutants, including Cr(VI), from the wastewater due to the availability of cheaper materials for the production of low-cost adsorbents [19,20].…”

A Review on Current Practices of Plastics Waste Management and Future Prospects

“…Improper management of plastics causes problems in many sectors including environment leading to global warming (Hoornweg & Bhadatata, 2015). Due to their lightweight, durability, and versatility, they find a diverse range of applications such as various household appliances, corrosion-protected pipelines, furniture, packaging materials, containers, automobile and aircraft parts, 3D printing (Azeez, 2018), bio-adsorbents (Pokhrel et al, 2019;Shrestha et al, 2019), for medical purposes (Phaiju et al, 2020), etc. Such applications of plastics and polymers led to their increased daily use in different forms and models.…”