PHOTOCATALYTIC DECONTAMINATION OF CHLORANTRANILIPROLE RESIDUES IN WATER USING ZnO NANOPARTICLES. DR. A. RAMESH, Ph.D, D.Sc.,

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1 PHOTOCATALYTIC DECONTAMINATION OF CHLORANTRANILIPROLE RESIDUES IN WATER USING ZnO NANOPARTICLES DR. A. RAMESH, Ph.D, D.Sc., 1

2 OBJECTIVES Determination of persistence and photolysis of chlorantraniliprole in water and at different ph conditions Liquid phase synthesis of ZnO nanorods Decontamination of residues of chlorantraniliprole in water using ZnO nanocatalyst LC-ESI-MS/MS confirmation of residues and its metabolites

3 SYNTHESIS OF ZnO NANOPARTICLES To.5 M Zinc acetate added.5 M of triethanolamine drop wise under nitrogen atmosphere Sonicated for 2 hours at 8 C Resulting light yellow colour precipitate was washed several times with Milli Q water Dried at 2 C in air for 2 hours Ref.: Rongguo Xie et al, Journal of physical chemistry B, 11, 26,

4 SEM IMAGE OF ZINC OXIDE NANORODS Particle size :.7 1. µm length; 1-15 nm Dia.

5 GAS CHROMATOGRAPHIC DETERMINATION OF CHLORANTRANILIPROLE Instrument - Shimadzu GC-14B Gas Chromatograph with Electron Capture detector Column - DB-5 Megabore (3m length x.53 mm I.D., 1. µm film thickness). Detector - 63 Ni Electron Capture Detector Temperature conditions Oven - 3 C Injector - 3 C Detector - 3 C Gas flow rate Nitrogen - 1 KPa Makeup - 5 KPa Current - 1 na Retention time (approximate) minutes

6 CALIBRATION - CHLORANTRANILIPROLE Concentration (mg/l) Peak area (µv-sec) LOD.1 mg/l BASED ON SIGNAL TO NOISE RATIO 3:1

7 EXTRACTION/DERIVATIZATION PROCEDURE Five ml of water sample was partitioned with 4 ml of hexane : ethyl acetate (5:5) mixture The organic layer was separated and evaporated to dryness and reconstituted the residues using acetonitrile with.15% ammonium hydroxide The content were placed in a heating block and held at 7 C for 2 hours. Partitioned with 2 x 5 ml portions of ethyl acetate Evaporated to dryness and reconstituted the residues with acetone

8 METHOD OF CALCULATION A x B x C Chlorantraniliprole content (ppm) = x F x D x E Where, A - Peak area in sample (µv-sec) B - Final volume of the sample (ml) C - Concentration of the standard (ppm) D - Peak area in standard (µv-sec) E - Volume of the sample (ml) F - Dilution Factor Conversion factor

9 RECOVERY OF CHLORANTRANILIPROLE IN WATER AT DIFFERENT ph LEVELS SUBSTRATES RECOVERY (%) Acidic water 95 Neutral water 93 Basic water 91 Milli Q water 96 LIMIT OF QUANTIFICATION.3 mg/l BASED ON SIGNAL TO NOISE RATIO 1:1

10 PERSISTENCE AND DECONTAMINATION OF CHLORANTRANILIPROLE RESIDUES IN WATER Fortified concentrations - 1. and 2. mg/l Water ph - 4., 7. and 9. Sampling occasions -, 1, 3, 5, 7, 1, 15, 2, 3 and 5 days after fortification. Photocatalysis with ZnO nanorods Optimum catalyst amount -.4 g/l Sampling occasions -, 3, 6, 9, 15 and 2 hours after fortification

11 DISSIPATION OF CHLORANTRANILIPROLE IN ACIDIC WATER WITHOUT CATALYST Dissipation of Chlorantraniliprole in Acidic Water Sampling occasion (Days) Residues (mg/l) Acidic water (ph 4) 1. mg/l 2. mg/l <LOQ.78 5 <LOQ <LOQ Residues in mg/l mg/l 2. mg/l Occasion in days DT 5 in days DT 9 in days 1. mg/l 2. mg/l 1. mg/l 2. mg/l

12 DISSIPATION OF CHLORANTRANILIPROLE IN NEUTRAL WATER WITHOUT CATALYST Sampling occasion (Days) Residues (mg/l) Neutral water (ph 7) 1. mg/l 2. mg/l <LOQ.77 2 <LOQ <LOQ 3 <LOQ <LOQ 5 <LOQ <LOQ Concentration in mg/l Dissipation of Chlorantraniliprole in neutral water mg/l 2. mg/l Occasion in days DT 5 in days DT 9 in days 1. mg/l 2. mg/l 1. mg/l 2. mg/l

13 DISSIPATION OF CHLORANTRANILIPROLE IN BASIC WATER WITHOUT CATALYST Sampling occasion (Days) Residues (mg/l) Basic water (ph 9) 1. mg/l 2. mg/l <LOQ.59 2 <LOQ <LOQ 3 <LOQ <LOQ 5 <LOQ <LOQ Concentration in mg/l Dissipation of Chlorantraniliprole in Basic Water mg/l 2. mg/l Occasion in days DT 5 in days DT 9 in days 1. mg/l 2. mg/l 1. mg/l 2. mg/l

14 DISSIPATION OF CHLORANTRANILIPROLE IN MILLI Q WATER WITHOUT CATALYST Sampling occasion (Days) Residues (mg/l) Neutral water (ph 7) 1. mg/l 2. mg/l <LOQ.77 2 <LOQ <LOQ 3 <LOQ <LOQ 5 <LOQ <LOQ Concentration in mg/l Dissipation of Chlorantraniliprole in milli Q Water mg/l 2. mg/l Occasion in days DT 5 in days DT 9 in days 1. mg/l 2. mg/l 1. mg/l 2. mg/l

15 TEMPERATURE AND LIGHT INTENSITY DURING PHOTOCATALYIC DEGRADATION OF RESIDUES Temperature Light intensity Temperature ( C) Intensity (lux) Time (hours) Time (hours)

16 Residues in mg/l Concentration in mg/l Photocatalytic degradation of Chlorantraniliprole in Acidic Water with ZnO Catalyst Dissipation of Chlorantraniliprole in Acidic Water without catalyst 1. mg/l 2. mg/l 1. mg/l 2. mg/l Occasion in hours Occasion in days Dissipation in acidic water with ZnO catalyst Sampling occasion (hours) Residues ( mg/l) Acidic water (ph 4) 1. mg/l 2. mg/l <LOQ <LOQ

17 2.5 Photocatalytic degradation of Chlorantraniliprole in neutral water with ZnO Catalyst Dissipation in neutral water with ZnO catalyst Concentration in mg/l mg/l 2. mg/l Occasion in hours Sampling occasion (hours) Residues ( mg/l) Neutral water (ph 7) 1. mg/l 2. mg/l Dissipation of Chlorantraniliprole in neutral water without catalyst Concentration in mg/l mg/l 2. mg/l <LOQ <LOQ Occasion in days

18 2.5 Photocatalytic degradation of Chlorantraniliprole in Basic Water with ZnO Catalyst Dissipation in Basic water with ZnO catalyst Concentration in mg/l mg/l 2. mg/l Occasion in hours Sampling occasion (hours) Residues ( mg/l) Basic water (ph 9) 1. mg/l 2. mg/l Dissipation of Chlorantraniliprole in Basic Water without Catalyst Concentration in mg/l mg/l 2. mg/l <LOQ <LOQ Occasion in days

19 Concentration in mg/l Concentration in mg/l Photocatalytic degadation of Chlorantraniliprole in Milli Q Water with ZnO catalyst 1. mg/l 2. mg/l Occasion in hours Dissipation of Chlorantraniliprole in milli Q Water without catalyst 1. mg/l 2. mg/l Dissipation in Milli Q Water with ZnO catalsyt Sampling occasion (hours) Residues ( mg/l) Milli Q water 1. mg/l 2. mg/l Occasion in days 2 <LOQ <LOQ

20 RATE CONSTANT, DT5 AND DT9 VALUES FOR DISSIPATION OF CHLORANTRANILIPROLE IN WATER Substrate Rate constant (k) day -1 DT 5 in days DT 9 in days 1. mg/l 2. mg/l 1. mg/l 2. mg/l 1. mg/l 2. mg/l Acidic Water Neutral Water Basic Water Milli Q Water

21 RATE CONSTANT, DT5 AND DT9 VALUES FOR DISSIPATION OF CHLORANTRANILIPROLE IN WATER IN PRESENCE OF ZnO NANORODS Substrate Rate constant (k) hr -1 DT 5 in hours DT 9 in hours 1. mg/l 2. mg/l 1. mg/l 2. mg/l 1. mg/l 2. mg/l Acidic Water Neutral Water Basic Water Milli Q Water

22 CONFIRMATION OF RESIDUES AND ITS BREAKDOWN PRODUCTS USING LC-ESI-MS/MS Dry gas : Nitrogen Collision gas : Helium Nebulizer : 4 psi Dry gas flow : 7 ml/min Interface Temp : 34 C Scan range : 1 to 55 m/z High capacity iontrap electrospray tandem mass spectrometry

23 HPLC SEPARATION PARAMETERS Instrument : Agilent 12 series HPLC with VWD detector Column : Xterra MS C18 (15 mm X 4.6 mm) Mobile phase A : Acetonitrile (.1% Formic acid) Mobile phase B : Milli Q Water (.1% Formic acid) Injection volume : 5 µl Flow program Time %B Flow

24 CHLORANTRANILIPROLE AND BREAKDOWN PRODUCTS IN WATER Molecular formula Molecular weight m/z Retention time in min MS2 Fragmentation ions m/z C 18 H 14 N 5 O 2 Cl 2 Br and 286 C 9 H 5 N 3 O 2 ClBr and 26 C 9 H 11 N 2 OCl C 17 H 12 N 5 O 2 C l2 Br and 286 C 18 H 15 N 5 O 2 ClBr and 25 C 18 H 15 N 5 O 2 Cl

25 EXTRACTED ION CHROMATOGRAM OF CHLORANTRANILIPROLE AND ITS BREAKDOWN PRODUCTS IN WATER EIC m/z 32 EIC m/z 484 Chlorantraniliprole EIC m/z 199 EIC m/z 44 EIC m/z 448 EIC m/z 468

26 ESI-MS/MS SPECTRA OF CHLORANTRANILIPROLE Intens. x MS2(483.8), 15.9min #(164) m/z Chlorantraniliprole m/z 483

27 ESI-MS/MS SPECTRA OF BREAKDOWN PRODUCTS Intens. x MS2(449.6), 15.8min #(152) m/z m/z m/z - 44 Intens. x MS2(44.4), 16.7min #(114) m/z

28 ESI-MS/MS SPECTRA OF BREAKDOWN PRODUCTS Intens. x Intens. x MS2(199.4), 14.2min #(944) m/z MS2(33.4), 13.9min #(921) m/z m/z - 32 m/z - 198

29 ESI-MS/MS SPECTRA OF BREAKDOWN PRODUCTS Intens. x MS2(469.8), 15.4min #(129) 468. m/z m/z

30 m/z C-N Cleavage DEGRADATION PATTERN OF CHLORANTRANILIPROLE IN WATER m/z Loss of CH 3 m/z 469 Loss of Cl m/z - 44 Loss of Br C-N Cleavage Chlorantraniliprole m/z 483 m/z - 32

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