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Chlorpyrifos Removal from Aqueous Solutions by Emulsion Liquid Membrane: Stability, Extraction, and Stripping Studies

Al-Damluji Farrah Emad, Mohammed Ahmed A.

Journal of Ecological Engineering

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2023

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Vol. 24, nr 2

101--111

EN

The current paper focuses on assessing key parameters affecting the extraction of Chlorpyrifos as well as emulsion stability using the emulsion liquid membrane technology. Five parameters affecting the extraction have been studied: homogenizer speed, emulsification time, agitating time, surfactant concentration, and stripping phase concentration taking into consideration the emulsion breaking. Experiments proved that using the resulting optimum values will maximize both extraction and stripping efficiencies (93.8% and 94.7% respectively), while minimizing the emulsion breakage (increasing the stability of emulsion) to 0.73% with no need to employ a carrier agent. A 10 min agitating time, 3% (v/v) Span 80 as a surfactant, 12700-rpm homogenizer speed, 0.25 M HCl as an internal phase concentration, and 5 min emulsification time are chosen to be the optimum parameters’ values. A study of extraction kinetics and estimation of mass transfer coefficient was also accomplished (3.89×10-9m/s). The conclusions of this work can be extended to the removal of other types of pesticides from water.

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Validation of UV Spectrophotometric and HPLC Methods for Quantitative determination of chlorpyrifos

Zalat O. A., Elsayed M. A., Fayed M. S., Abd El Megid M. K.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 2

58-63

EN

A specific and sensitive HPLC and UV spectrophotometric methodwere developed for determination and analysis of chlorpyrifos. Chromatographic separation was achieved on a 150 mm x 10 mm I.D. reversed phase column Zorbax SB C-18. usingdeionizedwater: acetonitrile in the ratio of 10:90 v/v respectively as mobile phase. The effluent was monitored at 290 and 230 nm. Two sharp peaks were obtained for the solvent and chlorpyrifos at 2.7 and 3.45 min respectively. UV spectrophotometric method was performed at 290 nm using Isopropanol as the solvent. Linear range was 0.025-3500 ppm (r2 = 0.9986 ±0.0009) for HPLC method and 2.229 to 200 ppm (r2 = 0.9988) for UV spectrophotometric method. Validation guidelines and statistical analysis showed that both the methods were precise, accurate, sensitive, and can be used for the routine quality control of chlorpyrifos in waste discharges.

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Monitoring of organophosphorus pesticides and remediation technologies of the frequently detected compound (chlorpyrifos) in drinking water

Derbalah A., Ismail A., Shaheen S.

Polish Journal of Chemical Technology

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2013

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Vol. 15, nr 3

25-34

EN

Studies on the currently used organophosphorus insecticides with respect to their environmental levels and effective remediation technologies for their residues in water have been considered as a source of major concern. This study was carried out to monitor the presence of organophosphorus in drinking water plants (Kafr-El-Shiekh, Ebshan, Elhamoul, Mehalt Aboali, Fowa, Balteem and Metobess) in Kafr-El-Shiekh Governorate, Egypt. Furthermore, it was carried out to evaluate the efficiency of different remediation technologies (advanced oxidation processes and bioremediation) for removing chlorpyrifos in drinking water. The results showed the presence of several organophosphorus pesticides in water sampling sites. Chlorpyrifos was detected with high frequency relative to other compounds in drinking water. Nano photo-Fenton like reagent (Fe2O3(nano)/H2O2/UV) was the most effective treatment for chlorpyrifos removal in drinking water followed by ZnO(nano)/H2O2/UV, Fe3+/H2O2/UV and ZnO/H2O2/ UV, respectively. Bioremediation of chlorpyrifos by effective microorganisms (EMs) removed 100% of the chlorpyrifos initial concentration after 23 days of treatment. There is no remaining toxicity in chlorpyrifos contaminated-water after remediation on treated rats with respect to cholinesterase activity and histological changes in kidney and liver relative to control. Advanced oxidation processes especially with nanomaterials and bioremediation with effective microorganisms can be regarded as safe and effective remediation technologies for chlorpyrifos in drinking water.