Enhancing profitability in p-xylene production via toluene methylation

•This study integrates toluene methylation (TM) into the PAREX process.•Aspen Plus and Energy Analyzer were used to simulate process and optimize energy.•Integrating TM and heat integration (HI) reduced the levelized costs.•Sensitivity analysis highlighted the mixed xylene price as the key cost driver. To address the growing industrial demand for para-xylene (PX), this study explores an alternative approach by employing toluene methylation (TM) to convert low-cost methanol into high-value PX. This study investigates the direct benefits of integrating TM with PX production. This study quantitatively evaluated the economic benefits of PX production and the investment costs of adding the TM process, considering the lack of toluene saleability. The process flow with a purity of 99.7% was simulated using Aspen Plus; the Aspen Energy Analyzer was used for heat integration (HI). The standalone PAREX process, PAREX integrated with TM, and PAREX with TM and HI showed levelized costs of 2,380, 2,341, and 2,325 USD/ton-PX, respectively. Furthermore, sensitivity analysis confirmed the price of the feed material (mixed xylene) to be the main factor influencing the process cost. This approach offers a promising pathway to enhance PX production capacity efficiently.