Tungsten Nitride, Well-Dispersed on Porous Carbon: Remarkable Catalyst, Produced without Addition of Ammonia, for the Oxidative Desulfurization of Liquid Fuel.

Polyanilines (pANIs), loaded with phosphotungstic acid (PTA), are pyrolyzed to get WO3 or W2N (approximate to 6 and approximate to 7 nm, respectively), which is well-dispersed on pANI-derived porous carbons (pDCs). Depending on the pyrolysis temperature, WO3/pDC, W2N/pDC, or W2N-W/pDCs could be obtained selectively. pANI acts as both the precursor of pDC and the nitrogen source for the nitridation of WO3 into W2N during the pyrolysis. Importantly, W2N could be obtained from the pyrolysis without ammonia feeding. The obtained W2N/pDC is applied as a heterogeneous catalyst for the oxidative desulfurization (ODS) of liquid fuel for the first time, and the results are compared with WO3/pDC and WO3/ZrO2. The W2N/pDC is very efficient in ODS with remarkable performance compared with WO3/pDC or WO3/ZrO2, which is applied as a representative ODS catalyst. For example, W2N/pDC shows around 3.4 and 2.7 times of kinetic constant and turnover frequency (based on 5 min of reaction), respectively, compared to that of WO3/ZrO2. Moreover, the catalysts could be regenerated in a facile way. Therefore, W2N/pDC could be produced facilely from pyrolysis (without ammonia feeding) of PTA/pANI, and W2N, well-dispersed on pDC, can be suggested as a very efficient oxidation catalyst for the desulfurization of liquid fuel.