Acid removal in cleaning processes

Abstract

Embodiments of the present disclosure include cleaning processes, cleaning machines, and methods of preventing acidification of a cleaning composition in a cleaning process. The cleaning process includes contacting an article having contaminants with a cleaning composition to remove the contaminants from the article, where the cleaning composition comes to have acidic components as a result of contacting the article with the cleaning composition, and where at least 85 percent by weight, based on a total weight of the cleaning composition, of the cleaning composition is an organic solvent, collecting the cleaning composition with the contaminants and the acidic components, separating the contaminants from the cleaning composition, and passing the cleaning composition with the acidic components over an ion exchange resin to remove the acidic components from the cleaning composition.

1 . A cleaning machine, comprising:
 a cleaning chamber in which can be loaded an article for a cleaning process, the article having contaminants on its surface;   a cleaning composition in the cleaning chamber, where the cleaning composition has at least 85 percent by weight of an organic solvent, based on a total weight of the cleaning composition, contaminants from the article, and acidic components acquired from the contaminants removed from the article or from side reactions occurring in the cleaning process;   a storage tank connected to the cleaning chamber, where the cleaning composition, the contaminants from the article, and acidic components are transferred from the cleaning chamber to the storage tank;   a distillation apparatus connected to the storage tank, where the distillation apparatus separates contaminants from the cleaning composition; and   an ion exchange resin connected to the distillation apparatus, where the ion exchange resin removes the acidic components in the cleaning composition.   
     
     
         2 . The cleaning machine of  claim 1 , where cleaning chamber, the storage tank, the distillation apparatus and the ion exchange resin form a closed-loop in which the cleaning composition moves. 
     
     
         3 . The cleaning machine of  claim 1 , where cleaning chamber is a closed cleaning chamber. 
     
     
         4 . The cleaning machine of  claim 3 , where the closed cleaning chamber includes a vacuum pump to reduce an atmospheric pressure inside the closed cleaning chamber. 
     
     
         5 . The cleaning machine of  claim 1 , where cleaning chamber is an open chamber. 
     
     
         6 . The cleaning machine of  claim 1 , where the ion exchange resin is also connected to the storage tank. 
     
     
         7 . The cleaning machine of  claim 1 , where the cleaning composition is transferred from the storage tank to the cleaning chamber. 
     
     
         8 . The cleaning machine of  claim 1 , where the ion exchange resin is an anion exchange resin. 
     
     
         9 . The cleaning machine of  claim 1 , where the ion exchange resin is in OH −  form. 
     
     
         10 . The cleaning machine of  claim 1 , where the ion exchange resin removes the acidic components from the cleaning composition semi-continuously. 
     
     
         11 . The cleaning machine of  claim 1 , where the cleaning composition contains less than 5 percent water. 
     
     
         12 . The cleaning machine of  claim 1 , where the cleaning composition is substantially free of water. 
     
     
         13 . The cleaning machine of  claim 1 , where the cleaning composition has a boiling point in a range of about 40 degrees Celsius to about 240 degrees Celsius. 
     
     
         14 . The cleaning machine of  claim 13 , where the cleaning composition has a boiling point in a range of about 90 degrees Celsius to about 200 degrees Celsius.