Porous carbonaceous solid acids derived from farm animal waste and their use in catalyzing biomass transformation

Abstract We demonstrate here the transformation of waste cow manure into N rich porous carbons (NPC) with large amount of micropores and large Brunauer–Emmett–Teller (BET) surface areas. The transformation process was achieved via carbonization of cow manure in presence of ZnCl 2 and FeCl 3 additives, without using additional templates. The resultant NPC could be converted into microporous carbonaceous solid acids (NPC-[C 4 N][X]) by quaternary ammonization of samples with 1,4-butane sultone, and ion exchanging with strong acids such as HSO 3 CF 3 and H 2 SO 4 . X-ray diffraction patterns and Raman spectra showed that NPC-[C 4 N][X] exhibit amorphous carbon network. N 2 isotherms and SEM images showed that NPC-[C 4 N][X] have abundant nanopores with large BET surface areas. XPS, FT-IR and elemental analysis results showed the N rich network in NPC support, has been successfully and homogeneously functionalized with strongly acidic ionic liquid and sulfonic groups. 31 P solid NMR spectra confirmed that NPC-[C 4 N][X] have typical Bronsted acid centers with strong and controllable acidity. Catalytic tests showed that NPC-[C 4 N][X] exhibits excellent activity and reusability in production of biofuels and fine chemicals through esterifications, transesterifications, and depolymerization of microcrystalline cellulose. This approach may provide a novel and cost effective way to recycle the waste cow manure into efficiently porous carbon based solid acids for heterogeneous acid catalysis.