Kappaphycus alvarezii seaweed belongs to the class of red alga (Rhodophyta). The granules obtained after recovery of "sap" (liquid plant stimulant) from freshly harvested alga is a promising biomass feedstock for energy application. Herein we report the kinetic behaviour of the granules using thermogravimetric analysis (TGA) at different heating rates in N-2 atmosphere and thermogravimetric-mass spectrometry (TG-MS) analysis. Sawdust as lignocellulosic biomass is considered for comparative study. Four different kinetic models (i) multilinear regression technique, (ii) Friedman method, (iii) Flynn-Wall-Ozawa (FWO) method and (iv) Kissinger-Akahira-Sunose (KAS) method are used to evaluate the apparent activation energy (E-a), the pre-exponential factor (A alpha) and the overall reaction order (n). Maximum SO2 peak at 300 degrees C and 950 degrees C (from TG-MS), indicates that slow pyrolysis at 500 degrees C, with a packed bed lime scrubber at the outlet during temperature rise, is the best suited thermochemical pathway for energy harnessing. (C) 2017 Elsevier Ltd. All rights reserved.