Review of Techniques to Characterize the Distribution of Chromate Contamination in the Vadose Zone of the 100 Areas at the Hanford Site

Topological control of metal–organic frameworks toward highly sensitive and selective detection of chromate and dichromate

“…2,3 Cooling water with an approximate Cr(VI) concentration of 700 μg kg −1 is discharged from the reactors to natural water bodies after cooling in retention basins. 4 As a consequence, high-level Cr(VI) contamination (ranging up to nearly 300 mg kg −1 ) has been identified in the groundwater at the Hanford site and the nearby Columbia river, which imposes a potential hazard to human health due to its high carcinogenicity. 4,5 Furthermore, the presence of chromate in high-level waste (HLW) leads to the formation of undesirable spinel crystals during the vitrification of nuclear waste, which increases the anticipated cost and risk of HLW vitrification.…”

“…4 As a consequence, high-level Cr(VI) contamination (ranging up to nearly 300 mg kg −1 ) has been identified in the groundwater at the Hanford site and the nearby Columbia river, which imposes a potential hazard to human health due to its high carcinogenicity. 4,5 Furthermore, the presence of chromate in high-level waste (HLW) leads to the formation of undesirable spinel crystals during the vitrification of nuclear waste, which increases the anticipated cost and risk of HLW vitrification. 6 Hence, facile detection and the subsequent effective sequestration of chromate and dichromate from contaminated water and HLW are highly indispensable.…”

“…[7][8][9][10][11] The concentration of Cr(VI) solution can be determined colorimetrically by the diphenylcarbazide method. 4 However, this technology suffers from low sensitivity (limit of detection of 0.5 mg kg −1 ). Instrumental techniques including inductively coupled plasma atomic emission spectroscopy (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) are advantageous in terms of limit of detection (LOD) 12 but they are unable to distinguish the toxic Cr(VI) from the benign Cr(III) ion, the latter of which is the dominant natural background species of chromium in sediments.…”