| 摘要 |
The invention relates to a method of preparing a smoke extract, which method comprises the steps of
i) preparing a tar from wood or cellulose preferably by pyrolysis,
ii) extracting one or more fractions of the tar with an extraction solvent in its supercritical state and/or an extraction solvent in its liquid state, said solvent in its supercritical state being selected from the group consisting of CO 2 , propane, methane, ethylene, ammoniac, methanol, water and mixtures of one or more of these solvents, said solvent in its liquid state being selected from the group consisting of CO 2 , propane and mixtures of these components,
iii) collecting at least some of the extracted tar to thereby obtain a smoke extract, wherein the extracted tar is collected from the solvent by removing the solvent from the non-dissolved part of the char, and reducing the pressure in one or more steps, wherein at least some of the extracted char is condensed in each step of pressure reduction. |
