CO2 production from degraded woods via a novel integrated pyrolysis-combustion process

The process of combustion produces minimal amounts of CO2 for conventional radiocarbon dating, making it difficult to estimate the age of the archaeological wood. Thus, the objective of this paper is to introduce a novel integrated pyrolysis-combustion process that will maximize the production of CO2. Degraded wood samples were assumed to be archaeological samples for this study, namely Karas (Aquilaria malaccensis), Meranti (Shorea acuminate) and Setumpol (Hydnocarpus spp.) were used for this process. The process of CO2 production was optimized by the application of design of experiment (DOE) and response surface method. The mathematical model was examined using the analysis of variance (ANOVA) at 5% level of significance. The temperature during the pyrolysis process, retention time and flow rates for the carrier gas (argon) were found to have a positive influence on the production of CO2. A second-order model was obtained to predict the production of CO2 as a function of temperature, retention time and flow rate. Optimum conditions for the production of CO2 were obtained at a pyrolysis temperature of 300 °C, 20 min retention and 980, 984 and 987.6 ml/min argon flow rate for Karas, Meranti and Setumpol, respectively. The optimized yields of carbon dioxide produced were 82.57, 79.7 and 84% for Karas, Meranti and Setumpol, respectively. The different yields of carbon dioxide were due to the carbon content in the individual samples.