Systems and methods for gas treatment

Abstract

A system and process for the recovery of at least one anesthetic from a gas stream including at least two anesthetics. The recovery includes adsorption by exposing the gas stream to an adsorbent. The adsorbent is then regenerated by exposing the adsorbent to a purge gas under conditions which efficiently desorb the at least two anethetics from the adsorbent. The at least two anesthetics (and impurities or reaction products) are condensed from the purge gas and subjected to fractional distillation to provide a recovered anesthetic.

What is claimed is: 
     
         1 . A process for the recovery of at least one anesthetic from a gas stream including a mixture of at least two different anesthetics, the process comprising:
 exposing the gas stream to at least one adsorbent having an organophillic pore lattice structure;   removing from the gas stream the at least one adsorbent containing the adsorbed mixture of at least two anesthetics;   regenerating the at least one adsorbent in a purge gas by exposing the at least one adsorbent to the purge gas under conditions which desorb the at least two anesthetics from the at least one adsorbent;   condensing the at least two anesthetics desorbed into the purge stream to provide a condensate comprising a mixture of the at least two anesthetics; and   distilling the mixture of at least two anesthetics to provide a purified at least one anesthetic at a medically acceptable purity level.   
     
     
         2 . A process according to  claim 1 , wherein the at condensing is performed at a predetermined temperature and pressure in a hydrocarbon condenser. 
     
     
         3 . A process according to  claim 2 , wherein moisture is removed from the purge gas in an aqueous condenser, a desiccant dryer, or both an aqueous condenser and desiccant dryer before the at least two anesthetics are condensed in the hydrocarbon condenser. 
     
     
         4 . A process according to  claim 1 , wherein the distilling is fractional distillation. 
     
     
         5 . A process according to  claim 4 , wherein the fractional distillation is performed under either a partial vacuum or increased pressure. 
     
     
         6 . A process according to  claim 4 , further comprising the step of washing the condensate with water before or after purification by fractional distillation. 
     
     
         7 . A process according to  claim 1 , wherein the condensate comprises a mixture of 2,2,2-trifluoro-1-fluoroethyl-difluoromethyl ether and 2,2,2-trifluoro-1-[trifluoromethyl]ethyl fluoromethyl ether. 
     
     
         8 . A process according to  claim 1 , wherein the at least one adsorbent is heated to an elevated temperature during regeneration of the at least one adsorbent to assist in desorption. 
     
     
         9 . A process according to  claim 8 , wherein the saturated adsorbent is heated with microwaves. 
     
     
         10 . A process according to  claim 8 , wherein the purge gas is heated to raise the temperature of the saturated adsorbent to the elevated temperature. 
     
     
         11 . A process according to  claim 8 , wherein the elevated temperature is in the range of 30° C. to 220° C. 
     
     
         12 . A process according to  claim 1 , wherein the purge gas is an inert gas or air. 
     
     
         13 . A process according to  claim 12 , wherein the purge gas comprises nitrogen. 
     
     
         14 . A system for the recovery of at least one anesthetic from a gas stream including a mixture of at least two different anesthetics, the system comprising:
 at least one adsorbent having an organophillic pore lattice structure placed in the path of the gas stream;   a regenerator in which the at least one adsorbent is placed to regenerate the at least one adsorbent in a purge gas by exposing the at least one adsorbent to the purge gas under conditions which desorb the at least two anesthetics from the at least one adsorbent;   a condenser connected with regenerator for condensing the at least two anesthetics desorbed into the purge stream to provide a condensate comprising a mixture of the at least two anesthetics; and   at least one distillation column for distilling the mixture of at least two anesthetics to provide the at least one anesthetic at a medically acceptable purity level.   
     
     
         15 . A system according to  claim 14 , wherein the at least one anesthetic is sevoflurane, desflurane, halothane, isoflurane or enflurane.