Separation of Organic Acids on Dowex Resins

Prepare 1 lb Dowex-1-chloride X-8 resin, 200-400 mesh. The same initial procedures can be used for any of the polystyrene type resins. 4-2. Suspend the resin in 2 liters distilled water. 

When the resin has almost completely settled, decant off the liquid containing the fines (small particles that settle only very slowly). 

Rinse the resin twice with 1 liter 95% ethanol to remove ethanol-soluble impurities. 

Suspend the resin in 2N HCl and heat to 100°C. Repeat this operation three to four times or until supernatant is clear and colorless, using fresh HCl each time. Allow the resin to cool for 1 hour each time before repeating the heating step. 

Divide the resin into two equal parts treat one part according to steps 4-9 to 4-15 and the second part according to step 4-16. 

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