Controlling Nanostructure And Porosity: The Influence Of High-Temperature Inert-Gas Pyrolysis And Time-Dependent Ball Milling On Coconut Shell Char

Pyrolyzed coconut shell char has potential applications in various fields, including energy storage and water purification. This study aims to investigate the effects of pyrolysis in inert atmosphere and size reduction of the char on the properties of coconut shell char. Coconut shell samples was pyrolyzed at 800 °C for 3 hours in a nitrogen atmosphere. The char obtained divided into three portions. Ball milling treatment at 250 rpm for 24 and 48 hours was applied to two separate portions of chars. The resulting chars were characterized for the morphological, textural and structural properties using scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) nitrogen adsorption, X-ray diffractometry (XRD), Fourier Transform Infrared spectroscopy (FTIR) and Raman spectroscopy method. The morphology revealed the particles to be agglomerated, irregularly shaped with rough surfaces and varying pore sizes. While possessing increased surface area of 196.255 m2/g for the untreated char to 361.244 m2/g for the 48 hours ball milled char. XRD patterns showed the presence of broad peaks centred between 2θ angles of 24º - 26º which are characteristic of a turbostratic carbon structure, while the ball milling effect shown progression in char’s crystalline order. The FTIR and Raman analyses indicated the existence of various functional groups (OH, C=O, C-O) and aromatic compounds (C=C). The graphitic character accompanied by the high surface area and mesoporous nature of the chars suggest that the pyrolyzed char may be a suitable precursor for graphene oxide synthesis. The results of this study provide valuable insights into the effects of thermal treatment and ball milling on coconut shell char properties.