Hypercross-linked lignite for NOx and CO2 sorption

•CO2 sorption capacity of hypercross-linked lignite coal was three fold higher than the virgin coal at 313K and 1atm.•The 29% of NOx sorption was achieved by hypercross-linked coal.•Formation of hypercross-linked conjugated quinonoid was confirmed by FT-IR and DRS UV–vis spectroscopy.•Presence of micropores was confirmed by BET and SEM analysis. We are reporting for first time, hypercross-linking of lignite for the sorption of NOx and CO2. Hypercross-linking was carried out with dimethoxy methane. The CO2 sorption capacity of hypercross-linked lignite coal was approximately three fold higher than the virgin coal at 313K and 1atm. 29wt% of NOx adsorption was observed at 298K and 1atm. Both the lignite and its hypercross-linked forms were characterized by Fourier transform infra red (FTIR), diffuse reflectance ultra violet–vis (DRS UV–vis) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Brunauer Emmet Teller (BET) adsorption isotherm and x-ray diffraction (XRD) studies.