Removal of sulfamethazine and sulfathiazole from water using modified bamboo biochar

Transcription

1 Removal of sulfamethazine and sulfathiazole from water using modified bamboo biochar Md. Boshir Ahmed (PhD, 2 nd Year) Principle Supervisor: Professor John L. Zhou Cosupervisor: Professor Huu Hao Ngo University of Technology Sydney (UTS), Sydney, Australia. USBI: 2016 Conference regon State University, Corvallis, R, USA 22 nd 25 th of August, 2016 School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney.

2 Contents About Antibiotic Properties and Differents Sorbents Biochar and Modified Biochar Preparation Properties, Isotherms, Kinetics and Details of Different Sorption Mechanism s Based on FTIR and Raman Spectroscopy, Resonance Effects and ph Shift Test. Summery

3 Antibiotics and Their Effects Antibiotics as emerging contaminants are of global concern due to the development of antibiotic resistant genes potentially causing superbugs. They are unique among medicines in that they act selectively on bacteria, among them the pathogens, while leaving cells and tissues unaffected (Ahmed et al., 2015). Impacts of antibiotics: Significance impacts on aquatic organisms on their survival, growth and body weight at μg L 1 mg L 1 concentration level. Can alter the microbial communities leading to the antibiotic resistance of some bacteria. May be absorbed eventually by humans through food chain and drinking water. Genotoxic effects

4 Price of Different Adsorbents Lower price Higher price Price of adsorbent ($/kg) BC AC Resin MWCNTs SWCNTs Adsorbent Fig. The price of different adsorbents (BC = Biochar, AC = Activated Carbon, MWCNTs = Multi Wall Carbon Nanotubes, SWCNTs = Single Wall Carbon Nanotubes (Ahmed et al., 2015). Ahmed, M. B., Zhou, J. L., Ngo, H. H., & Guo, W. (2015). Adsorptive removal of antibiotics from water and wastewater: progress and challenges. Sci. Total Environ. 532,

5 Biochar, Modified Biochar and Their Applications Biochar is a carbon dominant product which is obtained when biomass feedstock s are heated at elevated temperature in a closed reactor with little or oxygen hungry conditions even (Ahmed et al., 2016a). Modified biochar is obtained when biochar is further activated or modified either chemically or physically in order to improve their sorptive properties of contaminants (Ahmed et al., 2016b). Applications of Biochar: Sorptive removal of heavy metals, anionic contaminants, and organic including emerging contaminants Reduction of tracegas emissions from soil and atmosphere Bolster soil fertility agricultural and crop production Carbon sequestration Ahmed, M. B., Zhou, J. L., Ngo, H. H., & Guo, W. (2016a). Insight into biochar properties and its cost analysis. Biomass Bioenerg. 84, Ahmed, M. B., Zhou, J. L., Ngo, H. H., Guo, W., & Chen, M. (2016b). Progress in the preparation and application of modified biochar for improved contaminant removal from water and wastewater. Bioresour. Technol. 214,

6 Physicochemical Properties of Sulfonamide Antibiotics Class Compound Acronym CAS Number Sulphonamides (SAs) Sulfamethazine Sulfathiazole SMT SMZ K ow : ctanolwater partition coefficient & pk a : Acid dissociation constant logk ow pk a Molecular mass / / Molecular formula C 12 H 14 N 4 2 S, C 10 H 11 N 3 Na 3 S + [1] Moderately soluble in water and the logk ow indicates that they are moderately hydrophilic H 2 N CH 3 SMT + / SMZ + SMT / SMZ pk a1 H 2 N pk a1 S S NH pk a2 NH pk a2 N N N S CH 3 SMT SMZ R 1 R 2 N H 2 SMT 0 / SMZ 0 SMT +/ / SMZ +/ Sulfonamide species Sulfonamide structures S NH R 1 /R 2 General formula of sulfonamides At ph range: 03.00, SMT + species dominant At ph range: , SMT o species dominant At ph range: , SMT species dominant (Teixido et al., 2011) At ph range: 03.0, SMZ + species dominant At ph range: , SMZ o species dominant (negligible) At ph range: , SMZ species dominant (Fukahori et al., 2011)

7 Biochar and Modified Biochar Preparation Biomass Cut into small sizes Wash & drying at 105 C Pyrolysis at 380 C for 2 h at 2 psi Increased N 2 pressure 10 psi at 380 C for 15 minutes Cooling in room temp. Crushed into desired size, wash with DI & drying Biochar (BBC380) Biochar (BBC380) Soaking in 50% phosphoric acid solution Leave at 50 C for 3 h Heated at 600 C for 2 h at 2.0 psi Cooling in room temp. Wash with DI & adjust ph to 7.0 and dry Modified Biochar (1MbBBC 600)

8 Experimental Design: Pyrolyser N 2 Inlet Gasses utlet Vent Pyrolyser Head 4 Screws Valve Pyrolysis Chamber Furnace 3 N 2 Cylinder

9 Results Physicochemical Properties of Biochar and Modified Biochar Sample Composition data Yield dry basis (%) Moisture content (%) Ash (%) Volatile mater (%) Fixed carbon (%) Biomass Biochar Modified Biochar Initial ph Final ph Zeta potential (mv) 5.34± ± ± ± ±4.67 Sample EDS analysis BET surface area BJH Adsorption pore diameter C % % P % Molar /C Biochar m 2 g Å Modified Biochar m 2 g Å 1

10 Scanning Electron Microscopic (SEM) Picture of Biochar and Modified Biochar

11 Effect of ph on Distribution Coefficient (K d ) for (a)sulfathiazole (SMZ) and (b) Sulfamethazine (SMT) Sorption (a) (b) K d values (L Kg 1 ) K d values (L Kg 1 ) Initial ph Initial ph HPLC Analysis Method: Mobile Phase A (Acetonitrile : Formic Acid = 99.99% : 0.1%, v/v) and Mobile Phase B ( Milli Q Water : Formic Acid = 99.99% : 0.1%, v/v), Measured at 285 nm. Initial Flow Rate ml min 1 at 40% A and 60%B and At 0.10 min Flow Rate Change to 0.30 ml min 1 over 8 minutes.

12 Distribution Coefficient (K d ) values for Sulfamethazine (SMT) and Sulfathiazole (SMZ) Sorption

13 Pseudo first order (PF) and Pseudo second order (PS) kinetic model for SMT and SMZ sorption on modified biochar SMZ sorption on 1MbBBC600 SMT sorption on 1MbBBC600 PF kinetic model fit for SMZ PF kinetic model fit for SMT PS kinetic model fit for SMZ PF kinetic model fit for SMT 50 Q t (mg g 1 ) t (min)

14 Sorption Isotherm Models of Sulfamethazine (SMT) and Sulfathiazole (SMZ) q e (mg g 1 ) SMZ sorption data Langmuir Model Fit Frundlich Model Fit q e (mg g 1 ) SMT sorption data Langmuir Model Fit Freundlich Model Fit C e (mg L 1 ) C e (mg L 1 )

15 Sorption Isotherm Data Using Modified Biochar Freundlich Isotherm Parameter s Langmuir Isotherm Parameters Antibiotics At 21 ± 0.5 C Temperature At 21 ± 0.5 C Temperature K F n R 2 Q max K L R 2 SMZ 27.03± ± ± ± SMT 24.81± ± ± ± Kinetic Parameters PF at 21 ± 0.5 C PS at 21 ± 0.5 C Intraparticle Diffusion Model Name Q e cal (mg g K 1 (min R 2 Q e cal (mg g 1 ) K 2 (g mg 1 R 2 C (mg g 1 ) K i (mg g 1 R 2 1 ) 1 ) min 1 ) min 0.5 ) SMZ 56.71± ± ± ± SMT 37.46± ± ± ±

16 FTIR Spectra Based Sorption Mechanisms Abs H bending Raw Bamboo BBC380 1MbBBC600 SMT1MbBBC600 SMZ1MbBBC600 CH stretching vibration of asymmetric aliphatic CH, CH 2 & CH 3 H Group H group C= stretching Including ketone, CH, ester & anhydries 1690 C= i.e. carbonyl Bond Group 2340 C= stretching of CH Wave length (cm 1 )

17 Sorption Mechanisms Inferred from Raman Spectra Intensity (counts) (I D /I G = = 1MbBBC600SMT) BBC380 1MbBBC600 1MbBBC600SMT 1MbBBC600SMZ 3000 (I D /I G = =1MbBBC600.SMZ) (I D /I G = = 1MbBBC600) (I D /I G = = BBC380) Raman shift (cm 1 ) D and G bands refer to carbon SP 3 and SP 2 hybridization, respectively. Intensity ratio (I D /I G ) indicate the degree of graphitization

18 Schematic Sorption Mechanism t= o t= t Sorption affinites and K d values trend: SMZ>SMT.. H 2 N Diffusion SMT (R 1 ) SMZ (R 2 ) Higher electron density S at higher ph where negative species exist (less favorable).. H 2 N CAHB N H + + H R S H H H N H R N S at low ph + + electron acceptor + EDA.. : R + + Where, R=R 1 /R 2.. NH 2 H CAHB + R.. H 2 N H N S H H + H.. NH 2 at higher ph where negative species exist (mostly favored) S NH Lewis acid base interaction + EAA + R For neutral molecules R NH S H 2 N.. at high ph

19 Summery Phosphoric acid modified biochar (1MbBBC600) can be used as an alternate adsorbent to effectively remove emerging contaminants such as antibiotics. Adsorption distribution coefficient (K d ) values followed the trend of SMZ > SMT. Freundlich isotherm sorption parameters slightly better fits than Langmuir isotherm sorption parameters Mechanism of the sorption largely ph dependent and mostly governed by strong Hbond formation, + electrondonoracceptor (EDA), and by Lewis acidbase interaction at neutral region. Sorption at very low ph followed EDA interaction. At high ph, sorption was favored through H exchange with water molecule leading to formation of EAA interaction.

20 Acknowledgements Professor John L. Zhou Professor Huu Hao Ngo Dr Wenshan Guo IRS, FEIT Scholarships and Blue Sky Funding FEIT, Centre for Technology in Water and Wastewater (CTWW), and my colleges support in University of Technology Sydney (UTS), Sydney, Australia.

21 Thanks!! Questions??? Contact for Collaboration or Exchange: Professor John Zhou Head of School School of Civil & Environ. Eng. University of Technology Sydney (UTS) Tel: Mohammad Boshir Ahmed PhD Student (2 nd Year) Civil and Environmental Engineering University of Technology Sydney (UTS) Sydney, NSW, Australia.