Fast Pyrolysis Bio-oil

Viscosity

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

viscosity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 June 2013 to 12 July 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Test Guideline 114 (Viscosity of Liquids)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

rotational viscometer (dynamic)

Key result

Temp.:

20°C

Parameter:

dynamic viscosity (in mPa s)

Value:

125

Remarks on result:

other: at a shear rate of 5 s-1

Key result

Temp.:

20°C

Parameter:

dynamic viscosity (in mPa s)

Value:

137.9

Remarks on result:

other: at a shear rate of 100 s-1

Key result

Temp.:

40°C

Parameter:

dynamic viscosity (in mPa s)

Value:

190.7

Remarks on result:

other: at a shear rate of 5 s-1

Key result

Temp.:

40°C

Parameter:

dynamic viscosity (in mPa s)

Value:

117.4

Remarks on result:

other: at a shear rate of 100 s-1

Temp.:

20°C

Parameter:

other: Kinematic viscosity (in cm2/s)

Value:

1.065

Remarks on result:

other: at a shear rate of 5 s-1

Temp.:

20°C

Parameter:

other: Kinematic viscosity (in cm2/s)

Value:

1.174

Remarks on result:

other: at a shear rate of 100 s-1

Temp.:

40°C

Parameter:

other: Kinematic viscosity (in cm2/s)

Value:

1.649

Remarks on result:

other: at a shear rate of 5 s-1

Temp.:

40°C

Parameter:

other: Kinematic viscosity (in cm2/s)

Value:

1.015

Remarks on result:

other: at a shear rate of 100 s-1

Conclusions:

Oerall mean dynamic viscosity was found to be 121.1 mPa s at 20 °C and 129.2 mPa s at 40 °C. Due to immendiate sample segmentation into two phases, repeatable results were not possible to obtain and the results should be regarded as approximate values. 1.031 cm2/s

Executive summary:

The viscosity of Fast Pyrolysis Bio-oil was determined with a rotational viscometer according to OECD 114. The test was performed in duplicate at 20 °C and 40 °C. The viscosity was not constant with the shear rates. The samples were segmented into two phases immediately after stirring. Due to this inhomogeneity repeatable results were not possible to obtain and the resultd should be regarded as approximate values.

The mean results for the dynamic viscosity are:

20 °C: at a shear rate of 5 s^-1:       125.0 mPa s⁽¹⁾

at a shear rate of 100 s^-1:   137.9 mPa s⁽¹⁾

overall mean:                    121.1 mPa s⁽²⁾

40 °C: at a shear rate of 5 s^-1:       190.7 mPa s⁽¹⁾

at a shear rate of 100 s^-1:   117.4 mPa s⁽¹⁾

overall mean:                    129.2 mPa s⁽²⁾

The mean calculated results for the kinematic viscosity are:

20 °C, δ = 1.1742 g/cm³:  

at a shear rate of 5 s^-1:       1.065 cm²/s

at a shear rate of 100 s^-1:   1.174 cm²/s

overall mean:                    1.031 cm²/s

40 °C, δ = 1.1568 g/cm³:  

at a shear rate of 5 s^-1:       1.649 cm²/s

at a shear rate of 100 s^-1:   1.015 cm²/s

overall mean:                    1.117 cm²/s

Reference 2

Endpoint:

viscosity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 2015.

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: ASTM D1076-88

Deviations:

no

GLP compliance:

no

Type of method:

rotational viscometer (dynamic)

Key result

Temp.:

40°C

Parameter:

dynamic viscosity (in mPa s)

Value:

ca. 19.5

Remarks on result:

other: Sample 1, at a shear rate of 60 s-1 and spindel 18.

Key result

Temp.:

40°C

Parameter:

dynamic viscosity (in mPa s)

Value:

ca. 15.5

Remarks on result:

other: Sample 1, at a shear rate of 60 s-1 and spindel 18.

Key result

Temp.:

40°C

Parameter:

dynamic viscosity (in mPa s)

Value:

ca. 18.9

Remarks on result:

other: Sample 2 at a shear rate of 60 s-1 and spindel 18.

Key result

Temp.:

40°C

Parameter:

dynamic viscosity (in mPa s)

Value:

18.5

Remarks on result:

other: Sample 2 at a shear rate of 60 s-1 and spindel 18.

Conclusions:

The average for the dynamic viscosity 40 °C were 17.5 mPa s (Sample 1 Wood chips) and 18.7 mPa s (Sample 2 Forest residue).

Executive summary:

The viscosity of Fast Pyrolysis Bio-oil was determined with a rotational viscometer according to ASTM D1076-88. The test was performed at 40 °C for homogenised Fast Pyrolysis Bio-oil duplicate samples from Wood chips and Forest residue. The used share rate was 60 s-1 with spindel 18. The mean results for the dynamic viscosity were 17.5 mPa s (Sample 1 Wood chips) and 18.7 mPa s (Sample 2 Forest residue).

Description of key information

The viscosity of Fast Pyrolysis Bio-oil was determined with a rotational viscometer according to OECD 114 and ASTM D1076-88. The first test according to OECD 114 was performed in duplicate at 20 °C and 40 °C. The viscosity was not constant with the shear rates. The samples were segmented into two phases immediately after stirring. Due to this inhomogeneity repeatable results were not possible to obtain and the results should be regarded as approximate values. Viscosity was 121.1 mPa s at 20 °C.
In two ASTM D1076-88 accordant studies, the averages for dynamic viscosity were 17.5 mPa s (Sample 1 Wood chips) and 18.7 mPa s (Sample 2 Forest residue). The analyses were performed as duplicates. The used share rate was 60 s-1 with spindel 18. The average of these results was used as Key value for Chemical Safety assessment, as these samples represent full scale produced good guality Fast Pyrolysis Bio-oils.

Key value for chemical safety assessment

Viscosity:

18.1 mPa · s (dynamic)

at the temperature of:

20 °C

Additional information

According to literature, generic values for kinematic viscosity of wood pyrolysis liquids varies between 15 -40 cSt at 40 °C (Oasmaa & Peacocke 2010). In BIOTOX project, values ca. 47 - 226 cSt at 20°C and ca. 9 - 41 cSt at 50 °C respectively were measured.

According to Oasmaa et al. (1997), viscosities of pyrolysis liquids are a function of water content (see attachment: viscosity as a function of water content).

REFERENCES:

Anja Oasmaa & Cordner Peacocke. Properties and fuel use of biomass-derived fast pyrolysis liquids.

A guide. Espoo 2010. VTT Publications 731. 79 p. + app. 46 p.

BIOTOX. 2005. An assessment of bio-oil toxicity for safe handling and transportation. Final Technical Report. Part I: Publishable Final Report. Report drafted by Blin, J. Project N°: S07.16365. Project co-ordinator: Centre de Coopération Internationale de Recherche Agronomique pour le Développement (Cirad). Partners: Aston University, Bundesforschungsanstalt für Forst- und Holzwirtschaft (BFH).

Oasmaa, A., Leppämäki, E., Koponen, P., Levander, J. & Tapola, E. 1997. Physical characterisation of biomass-based pyrolysis liquids. Application of standard fuel oil analyses. Espoo, VTT. 46 p. + app. 30 p. VTT Publications 306. ISBN 951 -38-5051-X.