Ultimate and Elemental Analysis of Some Common Charcoal in Southwestern Nigeria

Common charcoals from different wood species were collected, identified and prepared for analysis. Ultimate and elemental analyses were carried out. In this study, identified charcoal were characterized. The result showed that in the ultimate analysis, Carbon, Hydrogen and Oxygen are the major content of the charcoal samples and are of great importance for the heating value. Sulphur and Nitrogen content were resent in low in quantity. XRF was used in the elemental analysis and the following elements were detected (Na, Cr, Ni, Cd, Al, K, Mn, P, Ca, Si, Mg, Ti, Fe) In the charcoal samples, the percentages of Si and Al are high while the percentages of (Cd, Fe, Na, Ti, Ni, Mg, P, K, Cr) were low. Percentage of silicon was between 50% to 65% in Albizia zygia, Milicia excelsa, Terminalia avicennioides, Funtumia elastica, Milletia thonningii and Hevea brsiliensis with Hevea brasiliensis having the highest which suggested high slagging propensity. Anogeissus leiocarpa, Afzelia bipindensis, Vitellia paradoxum, and Burkea africana have high Na/K. The ratio of Ca/ Mg is greater than 2 in all the samples. LOI ranges from 54.56 – 7.88% with a mean of 25.978±22.909%

Proximate analysis of some common charcoal in Southwestern Nigeria

analyses were carried out. The study aimed to characterize the identified charcoal and suggest the best charcoal that will give the minimal pollution effect. The result showed that the moisture content of the charcoal ranges between 3.26 and 8.40 wt% with an arithmetic mean of 5.36 ±1.50 wt%, the volatile content ranges between 3.05 and 13.62 wt% with an arithmetic mean of 7.20 ±3.55 wt%, the fixed carbon ranges between 76.83 and 90.57 wt% with an arithmetic mean of 83.54 ±4.60 wt%, and the ash content ranges between 3.09 and 5.18 wt% with an arithmetic mean of 3.87 ±0.70 wt%. The heating value of charcoal of different wood species were determined using Bomb calorimeter. Afzelia bipindensis has the highest ash content while Hevea brasiliensis has the lowest ash content. The heating value ranges 31.82–39.42 kJ/kg with a mean of 35.375 ±2.673 kJ/kg. This shows that Burkea africana could be best for use as a cooking fuel for households and restaurants because it has the best fuel property in terms of moisture content