Hexavalent Chromium Reduction with Zero-Valent Iron (ZVI) in Aquatic Systems

Abstract

Hexavalent chromium is a heavy metal used in a variety of industrial applications which is highly toxic to humans, animals, plants and microorganisms. Moreover, it is a well-established human carcinogen by the inhalation route of exposure and a possible human carcinogen by the oral route of exposure. Therefore, it should be removed from contaminated waters. Its reduction to trivalent chromium can be beneficial because a more mobile and more toxic chromium species is converted to a less mobile and less toxic form. During the last two decades, there has been important interest in using zero-valent iron (ZVI) as a Cr(VI)-reducing agent. A considerable volume of research has been carried out in order to investigate the mechanism and kinetics of Cr(VI) reduction with ZVI, as well as the influence of various parameters controlling the reduction efficiency. Therefore, the purpose of this review was to provide updated information regarding the developments and innovative approaches in the use of ZVI for the treatment of Cr(VI)-polluted waters.

Testing the suitability of metallic iron for environmental remediation: Discoloration of methylene blue in column studies

“…A new method to correlate intrinsic reactivity and treatability efficiency of metallic iron ( Metallic iron (Fe 0 ) is a reactive material currently used for environmental remediation and safe drinking water provision [1][2][3][4][5][6][7]. Available Fe 0 materials are obtained from various sources [8][9][10][11][12] and are supposed to satisfy design expectations [7,[13][14][15][16][17].…”

Electrospun Nanofibrous Polyacrylonitrile/calixarene Mats: an Excellent Adsorbent for the Removal of Chromate Ions from Aqueous Solutions

“…All of the reagents used in this study were obtained from analytical grade and used without further purification. [4]arene diester (4) and p-tert-butylcalix [4]arene diamide (5) compounds were synthesized according to the literature procedures.…”

“…The synthesis of desired calix [4]arene derivatives containing piperidine units at upper rim or lower rim is depicted in the Figure 1. For this purpose, the required starting materials, p-tert-butylcalix [4]arene (1), calix [4]arene (2) and diester derivative (4) were synthesized by following the procedure available in the literature.…”

“…For this purpose, the required starting materials, p-tert-butylcalix [4]arene (1), calix [4]arene (2) and diester derivative (4) were synthesized by following the procedure available in the literature. 18 In case, compounds (3) and (5) were prepared according to previous reports as follow.…”

“…3 On the other hand, Cr (III) is virtually both less toxic than Cr (VI) and required nutrient for living organisms. 4 The most commonly reported chronic effects of chromium (VI) exposure include contact dermatitis, skin ulcers, irritation and ulceration of the nasal mucosa and perforation of the nasal septum. Less common are reports of hepatic and renal damage and pulmonary effects (bronchitis, asthma, and bronchospasm).…”