Solvent substitution/solvent replacement
You may want to substitute an organic solvent with another one or another mixture that is
- more environmental friendly
- useful for reaction and workup
- removable for potential reuse
Strategy 1 with focus on solvent S to be replaced
This strategy implies that solvent S has been the optimal choice for the application. Solvent S and other chemically compatible solvents are placed in the HSP space. Similarity of alternative solvents can be ranked according to their distance to S where the best candidates have short distance to S. Solvent S can be replaced by a close neighbor solvent like C. But even 2 bad solvents like A & B here mixed in vol ratio A/B = 2/1 may substitute S if A and B are miscible.
Single solvents and solvent pairs are listed by increasing distance to S.
Strategy 2 with focus on the application of solvent S
This strategy tries to resemble the current process blend of reactants R and solvent S representet by the virtual reaction point T. The volume ratio of solvent S / reagents R define the position of T on the R-S line.
The alternative process with solvent A uses the same reagents R and has the virtual process point t. The distance T-t is minimized by moving t on the R-A line which defines the optimal volume ratio of solvent A / reagents R.
Two-component systems of reagents R and the alternative solvent A were ranked by increasing distance T-t.
This approach was successfully applied on an alkylation reaction, however the customer decided to keep the details unpublished.