Development Of Non-Ionic Silicone Surfactant-Based Extraction Methods Of Triazine Herbicides In Milk And Water Samples
| dc.contributor.author | Nur Izzaty Mohd | |
| dc.date.accessioned | 2021-02-02T01:03:22Z | |
| dc.date.available | 2021-02-02T01:03:22Z | |
| dc.date.issued | 2018-08 | |
| dc.description.abstract | Cloud point extraction (CPE) – spectrophotometric method had been developed for separation of atrazine and propazine using non-ionic silicone surfactant, polysiloxane polyether, as a new approach of triazine compounds extractor in the CPE. This type of surfactants was chosen as a green extraction solvent because of its structure and properties. There were two types of polysiloxane polyether (OFX 0309 and DC 193C) were studied in the CPE to investigate their effectiveness as extractor toward triazine compounds. Performance recovery of CPE can be observed when the following conditions was applied; CPE-OFX 0309, 1.0 mL 0.4 v/v % surfactant concentration, solution pH at 5, 2.0 M of Na2SO4, incubation time for 15 minute at 50 °C dan sample volume of 1mL at concentration of 10 mg/L while for CPE-DC 193C; the same conditions was applied except for concentration of salt used (1.5 M of Na2SO4). Using the optimized parameters, CPE was applied in milk and water samples. Langmuir model was found to fit well with the solubilization of the triazine compounds into the OFX 0309 and DC193C surfactant. Thus, Langmuir isotherm has been used to explain the solubilization study between surfactant and triazine compounds. The thermodynamic parameters were determined such as Gibbs free energy (ΔGº) which increases with temperature, value of enthalpy (ΔHº) and value of entropy (ΔSº) which increase with the surfactant hydrophobicity. The thermodynamic results indicated that the solubilization of the triazine compounds solubilized into the both surfactants were feasible, spontaneous and endothermic. Based on the performance of OFX 0309 in the developed of CPE method, the OFX 0309 surfactant was used to modify the surface of activated charcoal (AC) before coated with magnetic surfaces (AC-OFX MNPs) as adsorbent material. The OFX 0309 surfactant was chosen due to its properties that have flexible polysiloxane chain without any aromatic structure with compact micelles structure which provided good recoveries toward the triazine compounds. The synthesized material of AC-OFX MNPs was employed in magnetic solid phase extraction (MSPE). Due to magnetic properties of the AC-OFX MNPs material, the extraction with good extraction recovery was explored. Several parameters such as 20 w/v % of concentration surfactants used to modify the surface of AC, 15 mg of amount of sorbent, sample pH 5, 4 minute of extraction time, 300 μL of desorption solvent, 80 seconds of desorption time with using a mixture of acetonitrile: methanol and 15 mL of sample volume were optimized in the MSPE method. Using the optimized parameters, the newly synthesize AC-OFX MNPs was applied in milk and water samples to determine the recovery of MSPE method towards triazine herbicides coupled with high performance liquid chromatography with diode array detector (HPLC-DAD). | en_US |
| dc.identifier.uri | http://hdl.handle.net/123456789/11117 | |
| dc.language.iso | en | en_US |
| dc.publisher | Universiti Sains Malaysia | en_US |
| dc.subject | Herbicides | en_US |
| dc.title | Development Of Non-Ionic Silicone Surfactant-Based Extraction Methods Of Triazine Herbicides In Milk And Water Samples | en_US |
| dc.type | Thesis | en_US |
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