Publication

Abstract : The pyrolysis of stem and leaves of Hibiscus rosa sinensis was performed with and without Zeolite-5A using thermogravimetric analysis under nitrogen atmosphere for 125-to-1000-micron particles and 5 to 20 °C min-1 heating rate. The decomposition rates of hemicellulose, cellulose, and lignin were obtained by deconvolution of differential thermogravimetric data. Activation energy for catalytic pyrolysis was ∼25% lower than non-catalytic pyrolysis and was higher for lignin pyrolysis, due to a higher ratio of volatile matter to fixed carbon. The best-fit models for hemicellulose, cellulose, and lignin decomposition were nth-order, random-scission, and nucleation-A4. The pre-exponential factors were estimated from fundamental rate expression using best-fit model and activation energy, while thermodynamic parameters were estimated using Eyring equation. A lab-scale fixed-bed reactor was used to measure the product profiles under catalytic and non-catalytic conditions in the decomposition range of individual constituents. The liquid product yield was 15% higher for catalytic conditions.