Determination of total phenols in waters and wastewaters using flow injection with electrochemical detection; an alternative to the standard colorimetric procedure

Christophersen, M.J.; Cardwell, Terence J.

doi:10.1016/0003-2670(95)00614-1

Cited by 54 publications

(30 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Better limit of detection was obtained for sulphate with this method compared with that obtained with a FIA system (19 mg.dm -3 ) based on the formation of FeSO 4 + complex cation, but, in other hand, the linear range is smaller (25-600 mg.dm -3 ) [19]. In the phenolic compounds determination using this method we obtained slightly larger detection limits (0.03 mg.dm -3 ) than those obtained using a FIA system and linear range are similar when compared with the spectrophotometric and amperometric FIA systems [20,21].…”

Section: Analytical Figures Of Meritmentioning

confidence: 82%

Simultaneous determination of nitrite, nitrate, sulphate and phenolic compounds, by sequential injection analysis, in wastewaters

2000

View full text Add to dashboard Cite

There is an increasing need of process analysers to monitor water chemical parameters such as nitrite, nitrate, phenolic compounds and sulphate in natural water streams and industrial effluents due to the widespread industrial use of sulphuric acid [1], the increased use of nitrogen-based fertilizers over the last years [2][3][4] and the extensively phenolic compounds use as pesticides, herbicides and fungicides [5].The limits of emission values in the discharge of wastewaters, presented in the Portuguese Legislation [6] are 50 mg.dm -3 for nitrate, 2000 mg.dm -3 for sulphate and 0.5 mg.dm -3 for phenolic compounds.Automatic systems for on-line process control based on flow analyses were, already, developed and used in the monitorization of chemical species in wastewaters and industrial effluents. Flow injection analysis (FIA) has often been used as a technique to solve environmental analytical problems since its introduction by Ruzicka and Hansen in 1975 [7].The demand for mechanically simple and robust flow injection methodology, as advanced by the needs of process analytical chemistry, associated to reliability, long-term stability and low frequency of maintenance required for process analysers, have been the driving force behind developing a sequential injection technique. While manual reconfiguration of the flow channel, high reagent consumption due to continuous flow operation, frequent assistance of peristaltic pumps and frequent recalibration of the system is acceptable in laboratory applications, these are obstructive in terms of cost and manpower in a process environment. The sequential injection analysis (SIA) conceived comprising only a single propeller system, single valve and a single channel allows to overcoming the difficulties related to the conventional flow systems. Minimising the number of mechanical components is beneficial for a process control environment as it increases the reliability of the apparatus [8][9][10][11]. This paper describes a SIA system for the simultaneous determination of nitrite, nitrate, sulphate and phenolic compounds in wastewaters. The nitrite determination is based on the Griess-Llosvay reaction: nitrite ion is diazotized with sulphanilamide [12] and the product of diazotization is coupled with N-(1-naphthyl)-ethylenediamine (N1NED) to form a coloured azo dye which is measured spectrophotometrically at 540 nm. Nitrate is reduced on-line to nitrite in a copperized cadmium column and analysed as nitrite. The sulphate determination is based on the turbidimetric determination using barium chloride as reagent and the phenolic compounds determination (determination of the sum of compounds possessing a phenolic moiety) is based on the oxidative coupling with 4-AAP in alkaline solution, measuring the absorbances of the formed suspension and coloured compound, respectively, spectrophometrically at 540 nm. Abstract. A sequential injection analysis (SIA) system for the simultaneous determination of nitrite, nitrate, sulphate and phenolic compounds, in wastewaters has been deve...

show abstract

Section: Analytical Figures Of Meritmentioning

confidence: 82%

Simultaneous determination of nitrite, nitrate, sulphate and phenolic compounds, by sequential injection analysis, in wastewaters

2000

View full text Add to dashboard Cite

show abstract

“…The electrochemical oxidation of phenolic compounds on carbon based electrodes produces a polymeric nonconducting film on the surface when the reaction takes place, with the consequent loss of response [12,13]. Nevertheless, as previously reported, these same surfaces can be improved in their performance by the electrochemical deposition of polymeric films based on resole prepolymer mixtures of phenol (or some substituted phenols) and formaldehyde, that protect the surface from poisoning [12,14].…”

Section: Introductionmentioning

confidence: 86%

“…Coupling amperometric detection and flow injection analysis, has proved to be extremely useful for analytical applications, offering advantages like low detection limits, high sampling rate, possibility of coupling chemical reactors [15], very low sample volume, the use of inexpensive equipment and the accuracy of its results [12,13]. In a previous article [13] chemically modified electrodes with polymers made from resole mixtures with phenol, 4-hydroxybenzaldehyde and 4-hydroxybenzoate/formaldehyde was reported.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Determination of tert-Butylhydroxytoluene by Flow Injection Analysis at Polymer Modified Glassy Carbon Electrodes

Ortiz

1998

Electroanalysis

View full text Add to dashboard Cite

A flow injection method for the determination of the antioxidant BHT using polymer modified electrodes in connection with amperometric detection is proposed. The procedure is based on the electrochemical oxidation at 0.700 V (vs. Ag/AgCl[3M NaCl]) in phosphate buffer solution (pH 7.2). BHT is determined over the range 0.001-0.020 or 0.005-0.030 gL ¹1 . Other analytical parameters, such as electrode working potential, flow rate, electrodeposited charge and solution pH were optimized. The proposed method was applied to the determination of BHT in electrical transformer and vegetable oils samples. The results were compared with the HPLC-UV detection standard technique.

show abstract

“…This fact allowed us to develop a kinetic method for the determination of para-nitrophenol, applicable to waste water samples. Other methods are currently used for the determination of phenols including UV-VIS spectrophotometry [20][21][22], potentiometric [23,24] and amperometric methods [25,26] or high -performance chromatographic techniques [27][28][29]. Not so common methods like non -aqueous capillary electrophoresis [30] or enzyme -linked immunosorbent assay [19,31] were also employed for the determination of phenols.…”

Section: Introductionmentioning

confidence: 99%

A kinetic method for para-nitrophenol determination based on its inhibitory effect on the catalatic reaction of catalase

2005

View full text Add to dashboard Cite

The inhibitory effect of para-nitrophenol on the catalytic reaction of catalase was investigated. Michaelis-Menten kinetic parameters were determined from Lineweaver-Burk plots obtained in the absence or in the presence of the inhibitor. The inhibitor pattern, revealed by the Lineweaver-Burk plots, suggested a fully mixed inhibition mechanism. Spectrophotometric monitoring of the indicator reaction: H 2 O 2 catalase, para−nitrophenol − −−−−−−−−−−−−−−−− → H 2 O+ 1 2 O 2 in conjunction with initial rate measurements was employed for the kinetic determination of the inhibitor. Calibration plots of initial rate vs. para-nitrophenol concentration were linear in the concentration range 0.9·10 −5 -2.5·10 −5 mol/L and the detection limit was 3·10 −6 mol/L (417 µg/L) para-nitrophenol. Interferences from other phenolic compounds like orto-cresole, metaand orto-nitrophenol were observed.

show abstract

Determination of total phenols in waters and wastewaters using flow injection with electrochemical detection; an alternative to the standard colorimetric procedure

Cited by 54 publications

References 16 publications

Simultaneous determination of nitrite, nitrate, sulphate and phenolic compounds, by sequential injection analysis, in wastewaters

Simultaneous determination of nitrite, nitrate, sulphate and phenolic compounds, by sequential injection analysis, in wastewaters

Determination of tert-Butylhydroxytoluene by Flow Injection Analysis at Polymer Modified Glassy Carbon Electrodes

A kinetic method for para-nitrophenol determination based on its inhibitory effect on the catalatic reaction of catalase

Contact Info

Product

Resources

About