Potassium carbonate and water/alcohol/toluene?

Recently I did a distillation. At a certain point an azeotropic mixture of alcohol, water and toluene evaporated and was caught in a beaker with anhydrous potassium carbonate. I had to shake it and then pour it back into the reaction mixture (while filtering out the solid). 


Why did I have to catch it in a $\ce{K2CO3}$-mixture? 


(The product was diethyladipate)




The synthesis you are referring to is outlined [here](http://www.orgsyn.org/demo.aspx?prep=CV2P0264). Potassium Carbonate acts as a drying agent as you said as the later part of the distillation requires a specific temperature to remove the toluene and alcohol.


The water comes from the concentrated sulphuric acid solution added with apidic acid. The residue is also rinsed with alcohol which is a strong indicator that water needs to be removed. 


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