Digestate　from　Anaerobic　Digestion　(AD)　is　a　very　common　waste　produced　by　European　biogas　plants　and　its　current　method　of　reuse　is　as　a　fertilizer　or　as　soil　amendment.　This　in　turn　however　gives　rise　to　some　other　environmental　concerns　which　include　greenhouse　gas　emissions　and　volatilization　of　ammonia　causing　ammonia　pollution.　Biochar　is　an　environmentally　friendly　and　low-cost　product　for　CO2　capture　and　sequestration.　Thus,　we　have　provided　one　simple　method　to　convert　AD　digestate　into　biochar-based　sorbents　of　CO2.　In　addition,　the　nitrogen-functionalised　porous　carbon　has　been　reported　to　be　effective　in　improving　the　uptake　of　CO2.　However,　most　of　them　were　prepared　using　multiple　steps.　In　this　work,　N-doped　biochar　was　prepared　by　a　one-step　method　of　modifying　AD　digestate　by　urea.　The　results　show　that　the　addition　of　N　can　increase　CO2　uptake　significantly.　Thus,　the　adsorbent　modified　by　urea　with　a　ratio　of　1:1　results　in　the　highest　CO2　uptake　capacity　(1.22　mmol　g−1),　indicating　digestate＇s　potential　application　for　carbon　capture　and　storage.　©　2020　Elsevier　Ltd