[meerin]

I have read many papers about pyrolysis of biomass..and they used methanol as a collected medium for pyrolysis oil..
After that the bio-oil was separated from methanol by evaporation at temp of 78 C.
I would like to know about the evaporation technique used to separate bio-oil from methanol.
- the volatile pyrolysis compounds are vaporized during the heating 78 c or not ?
- aging reaction such as condensation reactions will occur during this heating period and changing bio-oil composition or not ?
and why do they commonly use the solvent as a collected medium in the pyrolysis process ?

Thank you very much

[vmelkon]

I would like to know about the evaporation technique used to separate bio-oil from methanol.

Probably a single stage distillation. They haven't posted a schematic at all in their papers?

- the volatile pyrolysis compounds are vaporized during the heating 78 c or not ?

You said "bio-oil". Oils tend to have a higher boiling point than water.
They probably chose 78 C because at 64 C (or whatever the exact number is), methanol boils and at 78 C, ethanol boils. It is possible that ethanol forms during pyrolysis (among many other compounds including methanol).

why do they commonly use the solvent as a collected medium in the pyrolysis process ?

I wouldn't know. Perhaps it helps to capture the vapors. Maybe someone else can answer that.

[SABRY]

- the volatile pyrolysis compounds are vaporized during the heating 78 c or not ?

and why do they commonly use the solvent as a collected medium in the pyrolysis process ?

Thank you very much

1. Any components of lower boiling point than 78 C will vaporizes such as naphtha

2. Using solvent for better product yields and processing economics.