Determination of phosphate in water by flow coulometry

Abstract

In this work, the possibility of flow coulometry application as coulometric titration was studied. The method was used to analyze phosphates in wastewater samples. The principle of the determination consisted in the formation of molybdophosphate and its subsequent one-electron electrolytic reduction. The present method is applicable under optimal conditions in the concentration range of 1.5 × 10−6 to 5.5 × 10−5 mol/dm3. Detection limit of the method is 3.42 × 10−7 mol/dm3. Mineralization step has been proved a problem in total phosphate content determination. If mineralization was not carried out, only inorganic soluble phosphates were determined. It is a new method characterized by its simplicity of instrumentation and handling, which is a prerequisite for its further use in the field of trace analysis.

Modeling the coulometric data for on-chip flow rate detection as a first order decay problem in a microfluidic device

“…The method in the present work can be performed using highly portable hand-held device and has a 3σ resolution of 3.64 µL/min. Coulometry measures the amount of electric charge required for electrochemical conversion [27]. It is widely used for quantitative analysis in electrochemistry and has current efficiency of 100% [27,28].…”

“…Coulometry measures the amount of electric charge required for electrochemical conversion [27]. It is widely used for quantitative analysis in electrochemistry and has current efficiency of 100% [27,28]. Variation of electrolysis current with time and flow rate was studied by Oruc et al [29] for Hydrogen generation applications.…”

Recent Advancement of the Sensors for Monitoring the Water Quality Parameters in Smart Fisheries Farming

“…Some researchers used graphene-based electrochemical sensing methods [60][61][62][63][64][65][66], whereas some researchers used the colorimetric [67] method for detecting phosphate in water samples. A summary of the existing phosphate sensors is included in Table 7.…”

“…Ag/rGO 5~6000 1.20 [60] Al2O3/rGO 1~10 1 [61] rGO/ferritin 16.7~500 0.806 [62] Co/Pt/C/Ag-AgCl 1~9500 0.3 [63] Poly vinyl chloride/Polyurethane 0.096~960 0.096 [64] Cobalt/Glass 1~3300 0.08 [65] Wax paper 4~300 4 [66] Coulometric titration 1.5~55 1.5 [67] 2.5. Calcium (Ca) and Magnesium (Mg)…”