DETERMINATION OF RESIN AND FATTY ACIDS IN PROCESS WATERS OF PAPER INDUSTRIES
A. Rigola, A. Latorreb, S. Lacorteb, D. Barcelób
aDept.
Química Analítica, Universitat de Barcelona, Spain bDept. Química Ambiental, IIQAB-CSIC, Spain
INTRODUCTION
Wood Extractives (resin acids, fatty acids, etc.) Dispersion in process waters
Mechanical problems
Pitch deposits on paper machine, specks in the paper, etc. End up in effluents, remain in the final product.
Accumulation in whitewaters
96-h LC50 (salmon or rainbow trout) High toxicity to fish Resin acids Unsaturated fatty acids 0.4-1.7 mg/L 2.0-8.0 mg/L
INTRODUCTION
Usual analytical methods
Extraction
Liquid-liquid Solid phase Methyl ester Trimethilsylis ester Pentafluorobencyl ester GC-FID GC-MS
Derivatisation
Measurement
Time consuming Low derivative stability High sample manipulation
Alternative method
LC-MS
Rapid results Minimise sample manipulation
WORKPLAN
Development of a LC-MS method for RA and FA determination Optimisation of MS parameters Optimisation of separation conditions (two columns) Determination of quality parameters Application to water samples from paper industries (two ways
for sample preparation) Comparison of results
Modification of a GC-FID existing method by using MS detection Determination of quality parameters Analysis of water samples Comparison of LC-MS and GC-MS results Toxicity assays Toxicity of standards Toxicity of water samples
COMPOUNDS: RESIN ACIDS (RA)
COOH
COOH
COOH
Pimaric
Sandaracopimaric
Isopimaric
COOH
COOH
COOH
COOH
Palustric
Levopimaric
Cl
Abietic
Neoabietic
Cl
Cl COOH COOH COOH COOH
Cl
Dehydroabietic (DHA)
12-ChloroDHA
14-ChloroDHA
12,14-DichloroDHA
COMPOUNDS: FATTY ACIDS (FA)
Saturated fatty acids
O ( )14 OH Palmitic O ( )15 OH Margaric O ( )16 OH Stearic
Unsaturated fatty acids
O O
( )7
( )7 Oleic
OH
( )4
( )7 Linoleic
OH
SAMPLES
Paper production (Portugal) P1 - Effluent
Pulp and paper production (Sweden) S1 - untreated Kraft pulp mill, pine, wastewater S2 - biologically treated S3 - untreated Printing paper mill, whitewater S4 - biologically treated at 37ºC S5 - biologically treated at 55ºC
S6 - open system, untreated Packaging board mill, whitewater S7 - open system, biologically treated S8 - closed system, untreated S9 - closed system, biologically treated
SAMPLES
Paper recycling (RIUDESA, Sant Pere de Riudebitlles, Catalonia)
R1 - Well water R4 - Entrance 30 mm filter R2 - Exit process water (paper machine) R5 - Exit 30 mm filter R3 - Entrance purifying plant system R6 - River
3 4 5
FLOCULANT APPLIED
30 mm FILTER
2
6 1
WELL WATER (8m) RIVER
SAMPLE PREPARATION
Dilution (0.8:0.2 sample: methanol)
TOXICITY ASSAY
Water sample (< 0.45 mm fraction)
LIQUID-LIQUID EXTRACTION
4 mL water + 2mL methyl t-butylether (3 × 2 min extractions)
MTBE phase
Evaporation (N2 stream)
GC-MS
Silylation (100 mL BSTFA + 50 mL trimethylchlorosilane)
Reconstitution (0.4 mL methanol)
LC-MS
INSTRUMENTS
HPLC system (Hewlett-Packard)
HP1100 autosampler HP1090A pump
HP1100 mass-selective detector
Trace GC-MS instrument (Termoquest)
ToxAlert®100 (Merck)
Area (x10 )
7
FIA
0
Pimaric Sandaracopimaric Isopimaric Palustric Levopimaric Abietic Neoabietic DHA ChlorDHA DichlorDHA Palmitic Margaric Stearic Oleic Linoleic
2 APCI ESI -
4
6
8
LC-MS: CHOICE OF LC-MS INTERFACE
Are a (x10 ) Are a (x10 )
0 10 10 2 4 6 8
7
7
0
2
4
6
8
P im aric Sandarac opim aric Isopim aric P alustric Le vopim aric Abie tic N e oabie tic DHA C hlorD H A D ic hlorD H A
Corona current (mA)
Fragmentor (V)
P alm itic M argaric O le ic Linole ic Ste aric
8
6
4
LC-MS: OPTIMISATION OF MS PARAMETERS (APCI -)
80
10
200
130
100
LC-MS: OPTIMISATION OF MS PARAMETERS (APCI -)
FIA
PARAMETER Drying gas flow (l/min) Nebulizer pressure (psig) Drying gas temperature (ºC) Vaporizer temperature (ºC) Capillary voltage (V) Corona current (mA) Fragmentor (V) VALUES ASSAYED SETPOINT 6, 8 40, 60 300, 325, 350 400, 500 3500 4, 6, 8, 10 80, 100, 130, 200 6 40 325 500 3500 8 100
LC-MS: MAIN IONS
RESIN ACIDS
Compound Pimaric Sandaracopimaric Isopimaric Palustric Levopimaric Abietic Neoabietic DHA ChloroDHA DichloroDHA Mw 302 302 302 302 302 302 302 302 336 370 [M-H] 301 301 301 301 301 301 301 299 333,335 367,369,371
FATTY ACIDS
Compound Mw [M-H] Palmitic Margaric Stearic Oleic Linoleic 256 270 284 282 280 255 269 283 281 279
LC-MS: OPTIMISATION OF SEPARATION CONDITIONS
LiChrospher 100 RP-18 (250 x 4 mm, 5 µm) Columns
Hypersil C8 (150 x 4.6 mm, 3 µm)
Organic solvents
Mobile phase H2 O
Acetonitrile or Methanol Acetone or Isopropanol
Unbuffered Buffered
25 mM HCOONH4 , pH 6.5
25mM CH3COONH4 , pH 7
Flow 1.0, 0.8, and 0.6 mL/min
Temperature
40ºC
LiChrospher 100 RP-18: STANDARDS CHROMATOGRAM
H2O pH 7: 30% 0%
30 min
Flow: 0.8 mL/min
Gradient
Methanol: 70%
100%
Single ion monitoring
m/z 299 Relative intensity m/z 333 DHA CHLORDHA RESIN 301
m/z 301 m/z 367 m/z 279
m/z 255
DICHLORDHA LINOLEIC
PALMITIC OLEIC
m/z 281 m/z 269
m/z 283
MARGARIC STEARIC
TIC (0.5 mg/mL) 5 10 15 20 25 30 Time (min)
Hypersil C8: SEPARATION CONDITIONS
Gradient
60 50 40 30 20 10 0 0 10 20 30 Time (min) 40
Methanol Isopropanol
H2O (pH 7, 25mM CH3COONH4)
Flow
0.8 mL/min
Temperature
40ºC
Hypersil C8: STANDARDS CHROMATOGRAM
Single ion monitoring
m/z 299 Relative intensity
DHA CHLORDHA RESIN 301
m/z 333 m/z 301 m/z 367
m/z 279 m/z 255 m/z 281 m/z 269
DICHLORDHA LINOLEIC PALMITIC OLEIC
MARGARIC STEARIC TIC (0.5 mg/mL) 5 10 15 20 25 30 35 Time (min)
m/z 283
WATER SAMPLE CHROMATOGRAM
LiChrospher 100 RP-18, extracted sample, single ion monitoring
Relative intensity
m/z 301 PALMITIC
m/z 299 DHA
m/z 255
RESIN 301
TIC
0 5 10 15 20 25 30 Time (min)
LC-MS: QUALITY PARAMETERS
C8 RA Linear range (mg/mL) R2 Repeatabilitya (%RSD, n=5) Reproducibilitya (%RSD, n=6) LDinst. (ng/mL) %Recoverya-Direct sample (n=3) %Recoverya-Extracted sample (n=3)
a Determined
C18 FA 0.5-10 > 0.99 2.8-4.3 3.9-8.7 55-325 75-89 89-97 RA 0.5-10 > 0.99 1.5-3.8 6.2-7.4 3.8-12.6 75-87 70-94 FA 0.5-10 > 0.99 2.9-7.4 6.2-9.5 1.9-7.8 76-86 70-82
0.05-10 > 0.99 1.1-4.7 3.7-5.3 5.2-30.6 75-95 89-101
at 1mg/mL level
LC-MS: Lichrospher 100 RP-18 vs Hypersil C8
Lichrospher 100 RP-18 ( m g/L)
DHA
400 300 200 100 0 0 100 200 300 400 Hypersyl C8 (m g/L)
Compound Palmitic DHA Resin 301
n 8 9 8
Slope
R
1.060 0.975 1.003 0.996 1.085 0.980
LC-MS: Direct sample vs Extracted sample
Resin 301, Hypersil C8
200
Direct sample (m g/L)
Compound
n
Slope
R
Hypersil C8
150
DHA
100 50 0 0 50 100 150 200 250 Extracted sample (m g/L)
8 7
0.993 0.996 0.902 0.991
Resin 301
Lichrospher 100 RP-18 DHA Resin 301 9 8 1.190 0.999 1.159 0.981
GC-MS: CONDITIONS
Column Injection Carrier gas Temperatures
Temperature (ºC)
HP-5 (30m x 0.25 µm, 0.25 µm) 5% phenyl methyl siloxane 1 mL, splitless Helium at 10 p.s.i., 1 mL/min Inlet 260ºC Ion source 200ºC GC Interface 270ºC
Gradient
300 200 100 0 0 10
4ºC/min
20 30 40 Time (min) 50
Electron impact
Ionising energy 70 eV
Emission current 150 mA
GC-MS: MONITORED IONS
Compound Response factor Palmitic 1.0 Margaric (i.s.) Linoleic 0.28 Oleic 0.41 Stearic 0.93 Pimaric 0.28 Sandaracopimaric 0.63 Isopimaric 1.1 Palustric 1.2 Levopimatic 0.55 DHA 0.31 Abietic 1.5 Neoabietic 0.68 ChlorDHA 1.5 DichlorDHA 0.82
Quantification ion 313 327 337 339 341 257 359 241 241 159 357 256 148 273 307
Other 73, 117, 132 73, 117, 132 73, 262 73, 117, 129 73, 117, 132 73, 121, 359, 374 73, 121, 241, 259 73, 256, 359 359, 374 73, 121, 374 239 241, 359, 374 73, 135, 374 73, 391 73, 425, 440
GC-MS: MASS SPECTRA
Resin acid: Pimaric
121.1 100 73.0 95 90 CH3 85 Si CH3 (TMS) 80 75 CH3 70 65 60 120.1 55 50 45 40 35 Loss of COOTMS 30 257.2 25 81.1 Loss of CH3 91.0 20 55.1 105.1133.1 238.1 359.2 M 15 147.1 161.1 374.2 10 173.1 87.1 1 258.2 5 284.2 332.2 375.2 292.2 0 50 100 150 200 250 300 350 400
Fatty acid: Palmitic
117.0
m/z
100 -COOTMS 95 73.1 90 85 CH3 80 75 Si CH3 (TMS) 70 CH3 65 75.0 60 313.2 55 132.1 Loss of CH3 50 45 -CH2-COOTMS 40 35 145.0 30 25 -CH2-CH2-COOTMS 20 55.1 314.2 15 10 201.1 83.1 146.1 269.2 285.2328.3 185.1 243.2 5 329.3 361.0 0 50 100 150 200 250 300 350 400 m/z
Relative Abundance
Relative Abundance
Relative intensity (x 108)
Palmitic
23 24 25 26 27 28
Pimaric Sandaracopimaric Isopimari Palustric c Levopimaric DHA
Margaric (i.s.) Linoleic Oleic Stearic
SIM CHROMATOGRAMS
29 30 31 Time (min)
Abietic
32
Neoabietic
33
ChlorDHA
STANDARD 7 mg/mL
34 35 36 37
R1
S6
DichlorDHA
GC-MS: QUALITY PARAMETERS
RESIN ACIDS Linear range (mg/mL) R2 Repeatabilitya (%RSD, n=4) Reproducibilitya (%RSD, n=5) LDinst. (ng/mL) %Revoverya (n=3)
a Determined
FATTY ACIDS 0.01-20 > 0.999 2-8 2-11 0.7-6 100-115
0.01-20 > 0.999 4-5 6-13 0.1-3 99-111
at 0.7ng injected level
GC-MS vs LC-MS
DHA
Compound Palmitic DHA Resin 301 n Slope R
15 0.988 0.953 9 7 0.860 0.982 1.030 0.983
RA AND FA IN WATERS OF PAPER INDUSTRY (mg/L)
Palm. DHA 46-49