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Removal of sulfamethazine and sulfathiazole from water using modified bamboo biochar
Md. Boshir Ahmed (PhD, 2nd Year)Principle Supervisor: Professor John L. Zhou
Co-supervisor: Professor Huu Hao NgoUniversity of Technology Sydney (UTS),
Sydney, Australia.
School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney.
USBI: 2016 ConferenceOregon State University, Corvallis, OR, USA
22nd -25th of August, 2016
Contents
About Antibiotic Properties and DifferentsSorbents
Biochar and Modified Biochar Preparation
Properties, Isotherms, Kinetics and Details ofDifferent Sorption Mechanism’s Based on FTIRand Raman Spectroscopy, Resonance Effects andpH Shift Test.
Summery
Antibiotics and Their EffectsAntibiotics 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. Geno-toxic effects
0.1
1
10
100
1000
10000
100000
1000000
BC AC Resin MWCNTs SWCNTs
Pric
e of
adso
rben
t ($/
kg)
Adsorbent
Lower price Higher price
Fig. The price of different adsorbents (BC = Biochar, AC = Activated Carbon, MWCNTs= Multi Wall Carbon Nanotubes, SWCNTs = Single Wall Carbon Nanotubes (Ahmed etal., 2015).
Ahmed, M. B., Zhou, J. L., Ngo, H. H., & Guo, W. (2015). Adsorptive removal of antibiotics from waterand wastewater: progress and challenges. Sci. Total Environ. 532, 112-126.
Price of Different Adsorbents
Biochar is a carbon dominant product which is obtained whenbiomass feedstock’s are heated at elevated temperature in a closedreactor 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 trace-gas emissions from soil and atmosphere Bolster soil fertility agricultural and crop production Carbon sequestration
Biochar, Modified Biochar and Their Applications
Ahmed, M. B., Zhou, J. L., Ngo, H. H., & Guo, W. (2016a). Insight into biochar properties and its cost analysis. Biomass Bioenerg. 84, 76-86.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, 836-851.
Class Compound Acronym CAS Number
logkow pKa Molecular mass
Molecular formula
Sulphonamides (SAs) Sulfamethazine Sulfathiazole
SMTSMZ
57-68-174-14-0
0.140.05
2.65/7.652.2/7.24
278.34255.32
C12H14N4O2S, C10H11N3NaO3S+ [1]
Kow: Octanol-water partition coefficient & pKa : Acid dissociation constant
Moderately soluble in water and the logKow indicates that they are moderately hydrophilic
Physicochemical Properties of Sulfonamide Antibiotics
S
O
O
NH
NH2
N
N
CH3
CH3
S
O
O
NHS
N
NH2
R1
R2
SMT
SMZ
SMT0/ SMZ0
SMT+/-/ SMZ+/-
SMT+/ SMZ+ SMT-/ SMZ-
pKa1
pKa1
pKa2
pKa2 NH2
S
O
O
NH R1/R2
Sulfonamide structures
General formula of sulfonamides
Sulfonamide species
At pH range: 0-3.0, SMZ+ species dominant At pH range: 3.00-6.0, SMZo species dominant (negligible)At pH range: 6.00-10, SMZ- species dominant (Fukahori et al., 2011)
At pH range: 0-3.00, SMT+ species dominant At pH range: 3.00-7.50, SMTo species dominant At pH range: 7.50-11, SMT- species dominant (Teixido et al., 2011)
Biochar and Modified Biochar Preparation
BiomassCut into
small sizes
Wash & drying at
105 °C
Pyrolysis at 380 °C for 2 h
at 2 psi
Increased N2pressure 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)
Experimental Design: Pyrolyser
3
4
Vent
Gasses OutletN2 Inlet
Pyrolyser Head
Furnace
N2 Cylinder
Valve
Pyrolysis Cham
ber
Screws
Results
1
Sample Composition data
Yielddry basis (%) Moisture content (%) Ash (%) Volatile mater (%) Fixed carbon (%)
Biomass 5.61 12.93 63.83 26.67
Biochar 43.50
Modified Biochar
Initial pH 1.62 3.00 4.35 6.13 10.00
Final pH 1.15 2.74 3.39 4.09 8.28
Zeta potential (mV) 5.34±0.32 -3.25±0.24 -12.76±1.23 -19.6±1.15 -45.9±4.67
Sample EDS analysis BET surface area BJH Adsorption pore
diameter
C % O % P % Molar O/C
Biochar 81.18 18.83 - 0.219 0.50 m2 g-1 113.5 Å
Modified Biochar 51.96 39.52 8.16 0.71 1.12 m2 g-1 83.8 Å
Physicochemical Properties of Biochar and Modified Biochar
Scanning Electron Microscopic (SEM) Picture of Biochar and Modified Biochar
Effect of pH on Distribution Coefficient (Kd) for (a)Sulfathiazole (SMZ) and (b) Sulfamethazine (SMT) Sorption
HPLC Analysis Method: Mobile Phase A (Acetonitrile : Formic Acid = 99.99% : 0.1% , v/v) andMobile Phase B ( Milli Q Water : Formic Acid = 99.99% : 0.1% , v/v), Measured at 285 nm.Initial Flow Rate 0.400 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.
20000
25000
30000
35000
40000
45000
50000
55000
60000
65000
70000
1 3 5 7 9 11
K dva
lues
(L K
g-1)
Initial pH
0
5000
10000
15000
20000
25000
30000
35000
40000
45000
50000
1 2 3 4 5 6 7 8 9 10 11
K dva
lues
(L K
g-1)
Initial pH
(a) (b)
Distribution Coefficient (Kd) values for Sulfamethazine (SMT) and Sulfathiazole (SMZ) Sorption
Pseudo first order (PFO) and Pseudo second order (PSO) kinetic model for SMT and SMZ sorption on modified biochar
0 200 400 600 800 1000 1200 1400
0
10
20
30
40
50
60
70 SMZ sorption on 1MbBBC600 SMT sorption on 1MbBBC600 PFO kinetic model fit for SMZ PFO kinetic model fit for SMT PSO kinetic model fit for SMZ PFO kinetic model fit for SMT
Qt (
mg
g-1)
t (min)
Sorption Isotherm Models of Sulfamethazine (SMT) and Sulfathiazole (SMZ)
0 10 20 30 40 500
10
20
30
40
50
60
70
SMT sorption data Langmuir Model Fit Freundlich Model Fit
qe
(mg
g-1
)
Ce (mg L-1)
SMZ sorption data Langmuir Model Fit Frundlich Model Fit
0 10 20 30 40 500
20
40
60
80
100
120
qe(
mg
g-1
)
Ce(mg L-1)
Sorption Isotherm Data Using Modified Biochar
Kinetic Parameters
PFO at 21 ± 0.5 °C PSO at 21 ± 0.5 °C Intra-particle Diffusion Model
Name Qe cal (mg g-
1)
K1 (min-
1)
R2 Qe cal (mg g-1) K2 (g mg-1
min-1)
R2 C (mg g-1) Ki (mg g-1
min-0.5)
R2
SMZ 56.71±1.70 0.00783 0.960 66.08±1.17 0.0001412 0.992 12.01±3.2 1.66±0.18 0.857
SMT 37.46±1.84 0.00627 0.907 43.30±1.18 0.0001840 0.963 7.25±1.49 1.08±0.08 0.921
Freundlich Isotherm Parameter’s Langmuir Isotherm Parameters
Antibiotics At 21 ± 0.5 °C Temperature At 21 ± 0.5 °C Temperature
KF n R2 Qmax KL R2
SMZ 27.03±0.946 2.6±0.072 0.998 127.7±18.87 0.058±.0105 0.995
SMT 24.81±2.77 5.94±1.253 0.915 65.74±6.25 0.208±0.087 0.897
FTIR Spectra Based Sorption Mechanisms
4000 3500 3000 2500 2000 1500 1000-0.01
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08 -OH bending 990-1020
1520
C=O stretching of -COOH
1690C=O stretching Including ketone, -COOH, ester & anhydries
2340C=O i.e. carbonyl Bond Group
2920
-CH stretching vibration of asymmetric aliphatic -CH, -CH2 & -CH3
Abs.
Wave length (cm-1)
Raw Bamboo BBC380 1MbBBC600 SMT-1MbBBC600 SMZ-1MbBBC600
-OH group3800-3900 3320
-OH Group
Sorption Mechanisms Inferred from Raman Spectra
500 1000 1500 2000 2500 3000-1500
0
1500
3000
4500
6000
7500
9000
10500
12000
13500
15000
(ID/IG =1.0056722= 1MbBBC600-SMT)
(ID/IG =0.849705= BBC380)
(ID/IG =0.991932 =1MbBBC600.SMZ)(ID/IG =1.056722 = 1MbBBC600)
Inte
nsity
(cou
nts)
Raman shift (cm-1)
BBC380 1MbBBC600 1MbBBC600-SMT 1MbBBC600-SMZ
1589-15991332-1345
D and G bands refer to carbon SP3 and SP2 hybridization, respectively. Intensity ratio (ID/IG) indicate the degree of graphitization
Schematic Sorption Mechanism
O O
O
O
OO
OO
O
O
H
H
H
H
H
H
OH
O
O HO H
NH2S
O
O
N-
R
NH2 S
O
O
N-
R
NH2 S
O
O
NH R
NH2
SO O
NH
R
NH2 S
O
O
N R
H
δ -
δ+
δ -
δ+
δ -
δ -
δ -
δ +
δ -
δ +
π
π π
π π
H
NH2S
O
O
NR
δ +
δ -
CAHB
CAHB
Lewis acid base interaction
SMT (R1)
SMZ (R2)
..
..
π π π
π
π π π
π
..
Diffusion
Higher electron density
..:
δ -
δ -
δ - δ+
δ+ δ+
electron acceptorπ
δ + δ + - EAA π π
δ -
δ - δ -
..
π - EDA
Where, R=R1/R2
π ..
..
π + at low pH
at high pH
For neutral molecules
at higher pH where negative species exist (mostly favored)
at higher pH where negative species
exist (less favorable)
t= t t= o
Sorption affinites and Kd values trend: SMZ>SMT
Summery
Phosphoric acid modified biochar (1MbBBC600) can be used asan alternate adsorbent to effectively remove emergingcontaminants such as antibiotics.
Adsorption distribution coefficient (Kd) values followed thetrend of SMZ > SMT.
Freundlich isotherm sorption parameters slightly better fits thanLangmuir isotherm sorption parameters
Mechanism of the sorption largely pH dependent and mostlygoverned by strong H-bond formation, π+-π electron-donor-acceptor (EDA), and by Lewis acid-base interaction at neutralregion. Sorption at very low pH followed π-π EDA interaction.At high pH, sorption was favored through –OH exchange withwater molecule leading to formation of π-π EAA interaction.
Acknowledgements
Professor John L. Zhou Professor Huu Hao NgoDr Wenshan Guo IRS, FEIT Scholarships and Blue Sky FundingFEIT, Centre for Technology in Water and
Wastewater (CTWW), and my colleges’ support in University of Technology Sydney (UTS), Sydney, Australia.
Thanks !! Questions ???
Mohammad Boshir AhmedPhD Student (2nd Year)Civil and Environmental EngineeringUniversity of Technology Sydney (UTS)Sydney, NSW, Australia.Email: [email protected]
Contact for Collaboration or Exchange: Professor John ZhouHead of SchoolSchool of Civil & Environ. Eng.University of Technology Sydney (UTS)Tel: +61295142023Email: [email protected]