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US 4,478,720 AGranted
Fractionation process for mixtures by elution chromatography with liquid in supercritical state and installation for its operation
AssigneeSociete Nationale Elf Aquitaine
InventorMichel Perrut
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Abstract
The present invention concerns a fractionation process of a mixture by elution chromatography. It is characterized in that the collected eluent is purified, restored to supercritical state and recycled in the head of the column. It concerns a cracking process of mixtures by elution chromatography with liquid in the supercritical state and an installation for its operation.
Claims14
A process for fractionating a mixture by supercritical fluid elution chromatography, said process comprising the steps of:
- (a) continuously feeding an eluent fluid in the supercritical state at a constant flow rate through an elution chromatography column;
- (b) periodically injecting an amount of a mixture to be fractionated into the supercritical eluent fluid at the head of the elution chromatography column;
- (c) detecting the emergence of fractions of said mixture in the supercritical eluent stream emerging from the elution chromatography column;
- (d) selectively directing portions of said supercritical eluent stream containing detected fractions of said mixture to individual separators of a bank of parallel separators;
- (e) separating mixture components from each eluent portion by allowing the supercritical eluent of each portion to expand in the separator to which it was directed;
- (f) withdrawing separated mixture components from the bottom of each separator;
- (g) withdrawing gaseous eluent from the top of each separator;
- (h) purifying the withdrawn eluent;
- restoring the purified eluent to the supercritical state, and
- (j) recycling the supercritical eluent from step (i) to step (a) such that the quantity of eluent present in the circuit of steps (a) through (j) is maintained constant.
7 more elements
Apparatus for fractionating a mixture by supercritical fluid elution chromatography, said apparatus comprising:
- (a) an elution chromatography column;
- (b) means for continuously feeding an eluent fluid in the supercritical state at a constant flow rate through said elution chromatography column;
- (c) means for periodically injecting an amount of a mixture to be fractionated into the supercritical eluent fluid at the head of said elution chromatography column;
- (d) means for detecting the emergence of fractions of said mixture in the supercritical eluent stream emerging from the elution chromatography column;
- (e) a bank of parallel separators selectively connectable to said detecting means;
- (f) means for selectively directing portions of said supercritical eluent stream containing detected fractions of said mixture to individual separators of said bank of said parallel separators;
- (g) means for allowing supercritical eluent to expand in said separators;
- (h) means for withdrawing separated mixture components from the bottom of each separator;
- (i) means for withdrawing gaseous eluent from the top of each separator;
- (j) means for purifying the withdrawn eluent;
- (k) means for restoring the purified eluent to the supercritical state, and
- (l) means for recycling the supercritical eluent from the purification means to the supercritical eluent feeding means.
9 more elements
Dependencies are inferred from the claim text.