Extraction of cellulose with subcritical and supercritical ethanol

Abstract

Cotton cellulose was extracted with ethanol in sub-and supercritical states dynamically. The degree of conversion was 95.4% and the extract yield was 55.2% when cotton cellulose was non-isothermally extracted with ethanol from 20°C to 400°C. From an engineering standpoint, in the temperature range from 200°C to 320°C, the rate of extract formation could adequately be described by a second-order reaction kinetics equation with the activation energy of 105.3 kJ/mol and the pre-exponential factor of 3.53×10⁷ s⁻¹. With the non-isothermal experimental technique, it was possible to determine the kinetic parameters; conversion degree and extract yield by one experiment.

Keywords

Cellulose / Ethanol / Supercritical fluid extraction / Thermal decomposition

References

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