Subcritical catalytic water oxidation for conversion DMAC waste carbon resources to acetic acid

Traditional approaches for wastewater treatment in chemical industry primarily emphasize the degradation of organic pollutants, resulting in excessive waste of carbon resources and carbon oxide emissions. This work studied on subcritical catalytic water oxidation for conversion N,N-Dimethylacetamide (DMAC), a significant organic polar solvent and extensively utilized in the chemical industry, into acetic acid. In the presence of zirconia catalyst, the parameter factors such as different crystalline forms of ZrO 2 , reaction temperatures, residence times, oxidation coefficient (O/C), and alkaline additives on the degradation efficiency of DMAC and the corresponding product distribution and acetic acid selectivity were examined and optimized systematically. Under a condition of 320 °C, 30 min, O/C = 1, NaOH = 50 mmol/L, and t -ZrO 2 = 5 wt%, the DMAC conversation rate reached 98.00 % with acetic acid yield of 37.25 % (selectivity of 93.97 %). In addition, the carbon balance of all intermediates was analyzed, and conformed that the carbon originating from DMAC was mainly converted into CO 2 and acetic acid. This work provides a new strategy on efficient conversion waste carbon resources into chemical product of organic acid, which is significantly contributed to carbon emission reduction worldwide.