Chromium removal from water using modified organic materials: A review

Chromium is a non-biodegradable element predominantly found in two chemical forms, Cr(VI) and Cr(III). Several remediation strategies have been implemented to achieve its removal from aquatic environments with limited results. This review article focuses on the analysis of removal strategies including the use of: (1) raw materials (agro-wastes, activated carbons, extracts and solutions) and (2) treated materials (alkaline and acid treatments). The article also reviews and analyses results obtained with surfactant modified organic biomasses. Although this review aims to summarise chromium removal techniques by highlighting relevant results of several studies, surface modification is outlined as a promising method to improve removal efficiency in aqueous solutions. The information presented in this article can help in the development of more efficient methods considering the improvements that surfactants may offer.