Determination of trace metals in high-salinity petroleum produced formation water by inductively coupled plasma mass spectrometry following on-line analyte separation/preconcentration

Abstract

A procedure is detailed for the determination of trace metals in high salinity petroleum produced formation water (PFW) by inductively coupled plasma mass spectrometry (ICP-MS) coupled with flow injection (FI) on-line matrix separation and preconcentration. High salinity PFW waters present complex composition containing various organic and inorganic substances. Mini-columns packed with Toyopearl AF-Chelate-650M iminodiacetate resin were used for the analyte separation/ preconcentration of Cd, Pb, Ni, Zn, V, Co and U; Toyopearl 8-hydroxiquinoline resin for Fe, and silica immobilized 8-hydroxyquinoline resin for Mo. A Doehlert matrix and desirability function was used to generate response surfaces to optimize the column separation/preconcentration parameters. Using 7.5 mL aliquots of PFW, method limits of detection of 0.0007, 0.009, 0.017, 0.024, 0.0002, 0.047, 0.058, 0.002, 0.013 and 0.041 ng ml À1 were obtained for Cd, Pb, Ni, Zn, U, Mo, Fe, Co, V and Mn, respectively. Vanadium, Co and Mn were determined by the method of standard additions whereas Cd, Pb, Ni, Zn, Mo, Fe and U were quantitated using isotope dilution. CASS-4 (coastal seawater) certified reference material was used for method validation and high-salinity PFW (39-120&) from Brazilian offshore platforms examined. The concentration ranges found in these waters were 0.

Ultrasound-assisted temperature-controlled ionic liquid microextraction for the preconcentration and determination of cadmium content in mussel samples

“…Among the extraction techniques currently being used for the preconcentration of Cd (II) are solid phase extraction (SPE) (Lemos, Bezerra, & Amorim, 2008;Oliveira et al, 2011), cloud point extraction (CPE) (Arain et al, 2014), liquideliquid extraction (LLE) (Mellah & Benachour, 2006), and coprecipitation (Prasad, Gopikrishna, Kala, Rao, & Naidu, 2006). Recently, the need for the development of rapid, simple, and versatile methods has led to the miniaturization of some extraction techniques, for example solidphase microextraction (SPME) (Tian, Cheng, Ye, Liu, & Jia, 2014) and liquid-phase microextraction (LPME) (Cunha & Fernandes, 2013).…”

Use of Functionalized Resin for Matrix Separation and Trace Elements Determination in Petroleum Produced Formation Water by Inductively Coupled Plasma Mass Spectrometry

“…Table 6 it is observed that the trace metal levels in the production formation waters analyzed did not exceed the Brazilian guidelines. The proposed method allows determining these five metals in lower limit of quantification than other methods previously published [4,28,30]. Also an online solid-phase extraction offers some additional advantage, in comparison to other methods, such as reutilization of solid phase for several cycles, simplicity, elimination of matrix effect, and low reagent consumption.…”

Determination of Copper and Cadmium in Petroleum Produced Formation Water by Electrothermal Atomic Absorption Spectrometry after Cloud Point Extraction

“…It is a practice throughout the oil industry, physically separating water from fluids and then discard them directly into the ocean or injecting it back into the wells or other suitable geological formations, with or without further treatment. 2 The PFW is a complex mixture constituting of the injection water, hydrocarbons residual, metals in the form of inorganic salts, radioactive materials and chemical residues added during the production and treatment process in the extraction.…”