A sensitive sequential non-chromatographic speciation analysis of chromium in natural/wastewaters by inductively coupled plasma optical emission spectrometry

Abstract

A highly sensitive and novel sequential non-chromatographic speciation procedure has been developed for selective pre-concentration and separation of Cr(III) and Cr(VI) from natural and wastewaters. In this procedure, Triton X-114 micelle and cetylpyridinium bromide-Triton X-114 mixed-micelle are used sequentially for the extraction of hydrophobic Cr(III)-trifluoropentanedione and hydrophilic Cr(VI), respectively. Inductively couple plasma optical emission spectrometry (ICP-OES) is used for its determination. The parameters affecting the extraction process are optimized. Under the optimized conditions, the pre-concentration factors obtained are 50 and 15 while limits of detection (LOD) are 0.02 and 0.05 ng mL À1 for Cr(III) and Cr(VI), respectively. These LODs are better than those of IC-ICP-MS and comparable to those of IC-ICP-DRC-MS methods. The recoveries are in the range of 95 to 99% at 10 to 40 ng mL À1 with relative standard deviation of 2-4%. The accuracy of the procedure is validated by comparing the sum of the concentrations of each individual chromium species obtained from sequential extraction with total chromium in BCR certified reference materials such as Effluent-713, Influent-714 and Industrial effluent-715. The method was then applied to various water samples collected locally.

Facile preparation of glutathione-stabilized gold nanoclusters for selective determination of chromium (III) and chromium (VI) in environmental water samples

“…Run-to-run ICP-OES [9,10], and ICP-MS [11], this method could be considered more economical and the sample treatments are more simple. Additionally, the use of a 96-well plate instead of a colorimetric cuvette made the detection procedure simple, fast and high throughput.…”

“…Over the past decades, various techniques for determination of Cr(III) and Cr(VI) have been developed, including electro-thermal atomic absorption spectroscopy (ETAAS) [4,5], spectrophotometry coupled with cloud point extraction [6] or solid phase extraction [7] or high-performance liquid chromatography [8], inductively coupled plasma optical emission spectrometry (ICP-OES) [9,10], and inductively coupled plasma mass spectrometry (ICP-MS) [11]. However, most of these methods involve complex and timeconsuming sample pretreatment procedures, and can only directly detect one valence state.…”

Atomic Spectrometry Update: review of advances in elemental speciation

“…It is difficult to see that this approach has much merit. Meeravali et al determined 125 Cr in the trichloroethylene extracts by ETAAS after mixing with methanol containing 2 % (V/V) nitric acid.…”

An Amyloid‐Fibril‐Based Colorimetric Nanosensor for Rapid and Sensitive Chromium(VI) Detection

“…In the case of wastewater, the nanosensor can also colorimetrically respond to 30-80 ppb of Cr VI (Figure S13 in the Supporting Information). Unlike other advanced instrumental methods (e.g., ion chromatography, [8] ICP-OES [9] and ICP-MS [10] ), the nanosensor does not require sophisticated and expensive instruments, tedious sample treatment, and skilled operators for Cr VI testing. With these advantages, the nanosensor can play a critical role in the frontline monitoring of Cr VI prior to the use of advanced instrumental methods for confirmatory Cr VI testing in laboratories.…”

“…Ion chromatography coupling to post-column chemical modification has been the conventional method for Cr VI detection. [8] Inductively coupled plasma optical emission spectrometry (ICP-OES) [9] and inductively coupled plasma mass spectrometry (ICP-MS), [10] as well as atomic absorption spectrometry (AAS), [11] can also detect Cr VI if they are used in combination with chromium-chelating agents in sample preparations. HPLC coupling to cloud-point extraction [12] and ionicliquid extraction [13] techniques have been reported for Cr VI analysis.…”