Divided wall column (DWC) configurations were simulated and optimized for five different feed's compositions to demonstrate the effect of feed composition and location of dividing wall in DWC in optimum operating conditions, energy requirement, operating, capital and total annualized cost (TAC) to produce market-grade benzene, toluene, and xylene. Operating conditions and cost for each DWC strongly depend on feed composition. Middle DWC (M-DWC) requires significantly lower energy compared with top and bottom DWCs except for feed dominated with xylene where energy requirement is comparable in studied configurations and M-DWC seems the best for ternary mixture separation.