Characterization of products from slow pyrolysis of palm kernel cake and cassava pulp residue

Slow pyrolysis studies of palm kernel cake (PKC) and cassava pulp residue (CPR) were conducted in a fixed-bed reactor. Maximum liquid yield (54.3 wt%) was obtained from PKC pyrolysis at 700 degrees C, heating rate of 20 degrees C/min, N-2 gas flow rate of 200 cm(3)/min and particle size of 2.03 mm. Fuel properties of bi-oils were in following ranges: density, 1.01-1.16 g/cm(3); pH, 2.8-5.6; flash point, 74-110 degrees C and heating value, 15 MJ/kg for CPR oil and 40 MJ/kg for PKC oil. PKC oil gave main contents of n-C-8-C-18 carboxylic acids, phenols, and esters, whereas CPR oil gave the highest amount of methanol soluble fraction consisting of polar and non-volatile compounds. On gas compositions, CPR pyrolysis gave the highest yield of syngas produced, while PKC pyrolysis offered the highest content of CO2. Pyrolysis chars possessed high calorific values in range from 29-35 MJ/kg with PKC char showing a characteristic of reasonably high porosity material.