A method of forming a dialkyl carbonate stream, includes obtaining a byproduct stream from a diaryl carbonate formation reaction that has alkanol, residual dialkyl carbonate, and residual aromatic compound. This byproduct stream is introduced to a distillation column to produce an alkanol tops stream and a first dialkyl carbonate bottoms stream. The alkanol tops stream is reacted with oxygen, carbon monoxide, and catalyst to form a second dialkyl carbonate stream that is introduced to the distillation column. The alkanol tops stream from the column contains alkanol, dialkyl carbonate, and less than 20 ppm aromatic compound. The first dialkyl carbonate bottoms stream from the column contains dialkyl carbonate, water, aromatic compound, and less than 2,000 ppm alkanol and is introduced to a water separation device to produce a product dialkyl carbonate stream and a water stream.