Microsticky Microsticky Measurements by Measurements by - - PowerPoint PPT Presentation

Microsticky Microsticky Microsticky Microsticky Measurements by Measurements by Measurements by Measurements by Headspace Gas Chromatography Headspace Gas Chromatography Headspace Gas Chromatography Headspace Gas Chromatography

X.S. Chai, J.C. Samp X.S. Chai, J.C. Samp

Institute of Paper Science and Technology Institute of Paper Science and Technology

Q.F. Yang, H.N. Song Q.F. Yang, H.N. Song

Guangxi University, China Guangxi University, China

J.Y. Zhu J.Y. Zhu

USDA Forest Products Laboratory USDA Forest Products Laboratory

Niagara Falls, ON, Canada Niagara Falls, ON, Canada September 24 September 24-

• 27, 2007

27, 2007

BACKGROUND

Stickies Stickies and and Microstickies Microstickies

Pass through 0.006 Pass through 0.006” ” slots slots TOC method: filtrate through 3,000 TOC method: filtrate through 3,000-

• 10,000

10,000 Dalton cut Dalton cut-

• off membrane
• ff membrane

Dissolved and colloidal form Dissolved and colloidal form

BACKGROUND

• Headspace Gas Chromatography (HSGC)

Headspace Gas Chromatography (HSGC) Headspace Gas Chromatography (HSGC) Headspace Gas Chromatography (HSGC)

Headspace (Vapor) Sample Sample Vial

HS GAS CHROMATOGRAPHY -

Vapor Vapor-

• Liquid Equilibrium Analysis

Liquid Equilibrium Analysis

Solute Water (Solvent)

Sample Sample Headspace

Vaporized Solute

PHYSICAL MODEL

Solute Water Adhesive

HSGC: MICROSTIKIES HSGC: MICROSTIKIES MEASUREMENTS MEASUREMENTS

Water Water Toluene Toluene + Adhesives + Adhesives Adhesives Toluene GC Signal Vaporized Solute

S k C K C

l g 1

/ − =

MATHEMATICAL MODEL

S S apparent effective surface area apparent effective surface area k k1 1 adsorptivity adsorptivity of the solute on

• f the solute on

the polymer substances the polymer substances k k hydrophobic characterization coefficient hydrophobic characterization coefficient

• f the polymers
• f the polymers

ρ density of sticky material density of sticky material d d average diameter of average diameter of microsticky microsticky particles particles

d m k S

s

⋅ = ρ

A b a C b a m

g s

⋅ − = ⋅ − = '

EXPERIMENTAL

Four Commercial Adhesives Four Commercial Adhesives

Carbtac Carbtac Avery acrylic Avery acrylic HYCAR 26288 HYCAR 26288 Unknown PSA Unknown PSA

Key Chemical Composition Key Chemical Composition

Polyacrylates Polyacrylates ( (e.g., e.g., PMMA) and Co PMMA) and Co-

• polymer

polymer

Particle Size in 50 Particle Size in 50 ppm ppm Solution: 0.7 Solution: 0.7 μ μm m

EXPERIMENTAL

HS GC Conditions HS GC Conditions

Flame ionization detector (FID) Flame ionization detector (FID) 30 m Capillary Column (HP 30 m Capillary Column (HP-

• 5)

5) Headspace with in Headspace with in-

• house made compressed air

house made compressed air cooling conduit: to temperature 32 cooling conduit: to temperature 32o

• C

C

Sample Sample

85 85 ppm ppm ( (v/v v/v) 10 ) 10 μ μL L toluene toluene-

• methanol

methanol added to added to 5 5 mL mL sample in a 20 sample in a 20 mL mL vial ( vial ( toluene= toluene=170 ppb) 170 ppb)

WITHOUT A HEADSPACE SYSTEM?

5 mL sample 10 mL Toluene-methanol

EQUILIBRIUM OF THREE PHASE SYSTEM

2 4 6 8 10 12 14 16 20 40 60 80 100 120 140

• Temp. = 32
• C

PSA = 1000 ppm

GC signal Equilbration time, min.

PHYSICAL MODEL

Adhesive

Surface effect Surface effect – – Surface area or Surface area or particle size particle size Adhesive type Temperature Solute/Adhesive content

PRELIMINARY RESULTS

200 400 600 800 1000 0.7 0.8 0.9 1.0 32

• C

60

• C

Toluene content 170 ppb 400 ppb 170 ppb

Normalized GC signal Polyacrylate added, ppm

101.4 0.1 101.4 1,000 99.6 300 98.3 1,000 100.6 0.08 100.6 800 101.4 200 99.7 800 101 0.06 101.0 600 100.7 120 98.9 600 99.5 0.04 99.5 400 100.9 80 99.9 400 100.4 0.02 100.4 200 99.0 40 100.1 200 100.8 100.8 100.4 99.9

GC signal Content mol/L GC signal Content (ppm) GC signal Content (ppm) GC signal Content (ppm)

NaCl Starch Clay Fine

Matrix Effect

200 400 600 800 1000 0.70 0.75 0.80 0.85 0.90 0.95 1.00 R

2 = 0.9926

T = 32

• C, 10 min

Carbtac PSA Avery acrylic HYCAR 26288

Normalized GC signal Amount of microstickies, ppm

CALIBRATION

s

m A ) 10 4 . 8 ( 10 686 . 1 ) 005 . ( 996 .

6 4 − −

× ± × − ± =

VALIDATION

200 400 600 800 1000 200 400 600 800 1000

Standard added (ppm)

Data

y = 0.942x, r = 0.989

HSGC Measured (ppm)

SUMMARY

Demonstrated a HSGC technique for the Demonstrated a HSGC technique for the determination of the amount of determination of the amount of microstickies microstickies in white water. in white water. Toluene is an effective agent that can sens Toluene is an effective agent that can sense e the change of the amount of the change of the amount of microstickies microstickies in in white water. white water. Headspace temperature 32 Headspace temperature 32o

• C seems effective

C seems effective for the technique. for the technique. For the limited studies conducted, the four For the limited studies conducted, the four adhesives have similar behavior for HSGC adhesives have similar behavior for HSGC measurements. measurements.

SUMMARY

The effect of the particle size of The effect of the particle size of microstickies microstickies needs to be studied in the future. needs to be studied in the future.