Mohammed A, Bello A, Habibu U, Mohammed U G, Abubakar G I and Aisha F (2017). Catalytic effect of Kaolin on the pyrolysis of Sawdust and Poultry wastes to produce Biochar for CO2 Sequestration, Nigerian Journal of Engineering and Applied Sciences (NJEAS), Vol. 4, No. 1, 118–130

Abstract

There is an increasing realisation that biomass and organic waste are valuable feedstock for pyrolysis process that produces biochar, bio oil and biogas. The oxides such as aluminum oxide (Al2O) and calcium oxide (CaO) could have catalytic effect on biochar production from biomass. To study the catalytic effect of Kaolin, the raw Kaolin was calcinated, acid modified and characterised. Sawdust (SD) and poultry waste (PW) biomass were impregnated with the modified Kaolin at different ratio (25 wt.%, 50 wt.%, and 75 wt.%) and subjected to pyrolysis at temperature between 300oC and 600oC. The biochar produced were analysed, characterised and the carbon sequestration potential was evaluated hypothetically. The result showed that co-pyrolysis of SD impregnated with 25 wt.% of Kaolin (SDK25) increased the biochar yield by 25 wt.% and carbon sequestration potential by 10 wt.% as compared to PW impregnated with 25 wt.% Kaolin (PWK25) which increased biochar yield by 16 wt.% and carbon sequestration potential by 5 wt.%. Fourier Infrared Spectroscopy (FT-IR) spectra displayed that all biochar at 500oC contain C-H alkyl group and aromatic band at 157 cm-1 which may impact positively on nutrient and water retention. Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD) analyses showed the development of well defined pores for biochar produced at 500oC, while the Brunauer-Emmett-Teller (BET) analysis showed that the biochar produced from the two biomass has a good surface structure and characteristics (surface area: 410 m2.g-1 and 276.3 m2.g-1) and could be employed as adsorbent in CO2 adsorption