Characteristics of coconut frond as a potential feedstock for biochar via slow pyrolysis

Abstract

The aim of this study is to investigate the potential of coconut frond as a feedstock for biochar production via slow pyrolysis process. Proximate, elemental and thermogravimetric analysis were performed to evaluate the chemical and thermal properties of the coconut frond. The percentage of its lignocellulosic component and high heating value were determined. Surface morphology of coconut frond was examined using field emission scanning electron microscope (FESEM). Coconut frond (CF) contains 78.03±3.91 d.b. wt% of volatile matter, 4.96±0.07 d.b. wt% of ash content and 17.01±3.86 d.b. wt% of fixed carbon. Elemental analysis revealed a sulfur content of 0.94±0.12 %, while the percentage of nitrogen is 0.46±0.33%. The composition of carbon and hydrogen are 34.0±6.22 % and 7.71±0.34 % respectively. The high heating value of CF is 17.77±0.40 MJ/kg. CF consists of 43.91±1.80 % cellulose, 31.58±1.20 % hemicellulose, and 18.15±0.60 % lignin. From thermogravimetric (TG) analysis, it is apparent that the weight loss of CF occurred prominently in the temperature range 200°C - 400°C. The peaks of the DTG curve at 281.75±0.35 °C and 334.08±0.35°C indicate the weight loss of coconut frond sample due to the degradation of hemicellulose and cellulose, respectively. The FESEM images of CF show its fibrous strands are compact with a few large pores with diameters around 42.5 - 48.1 μm large pores in the center of the CF sample. The results of the analysis show that CF has a potential as a feedstock for biochar production via slow pyrolysis. CF also can be used in other application such as syngas and bio-oil production due to the low lignin percentage and high volatile percentage.