SOLVENT EXTRACTION FROM BIODEGRADABLE MICROPARTICLES

摘要

Embodiments may also include a system for reducing a solvent concentration in a plurality of microparticles. The system may include a solvent extraction tank. In the solvent extraction tank, a mixture including the plurality of microparticles and the solvent may be contacted with water to form an aqueous suspension. A first portion of the solvent may dissolve into the water of the aqueous suspension to reduce the solvent concentration in the plurality of microparticles. The system may also include a concentration unit in fluid communication with the solvent extraction tank. The concentration unit may further reduce the solvent concentration in the plurality of microparticles. A microparticle concentrate may be formed. The system may further include a washing unit. In the washing unit, the microparticle concentrate may be contacted with a washing solution and may form an amalgam of washed particles.

主权项

1. A system for reducing a solvent concentration in a plurality of microparticles, the system comprising:
a solvent extraction tank where a mixture comprising the plurality of microparticles and the solvent are contacted with water to form an aqueous suspension; wherein a first portion of the solvent dissolves into the water of the aqueous suspension to reduce the solvent concentration in the plurality of microparticles from a first solvent concentration in the mixture to a second solvent concentration in the aqueous suspension; a concentration unit in fluid communication with the solvent extraction tank, wherein the concentration unit further reduces the solvent concentration in the plurality of microparticles from the second solvent concentration to a third solvent concentration by:
(i) introducing additional water to the aqueous suspension in the concentration unit; and(ii) removing at least a portion of the water and at least a portion of the solvent from the aqueous suspension in the concentration unit, wherein the additional water is introduced at a slower rate than the water and the solvent are removed from the concentration unit to form a microparticle concentrate with the third solvent concentration; and a washing unit adapted to receive the microparticle concentrate from the concentration unit, wherein the microparticle concentrate is contacted in the washing unit with a washing solution to form an amalgam of washed microparticles with a fourth solvent concentration.