Preparation and characterisation of graphitic biochar materials derived from rose oil industry waste via different pyrolysis durations and ball milling for advanced composites

Abstract

The valorisation of waste from rose-based industrial products produces value-added substances and paves the way for advanced composites. The rose waste generated from the essential oil industry of the Taif rose (Rosa damascena trigintipetala Dieck) is significant, and its management or disposal is a source of concern. In this study, it was valorised to produce a value-added nanomaterial. The synthesis of biochar nanoparticles via high-energy ball milling has gained tremendous research interest in recent times because of its low cost and eco-friendliness. Ball milling is a solvent-free technology with strong potential for waste volatilisation and eco-sustainability through the production of engineered biochar nanoparticles. Different biochar samples were produced and characterised to harness the synergistic combination of biochar production and ball milling. They were prepared at a constant pyrolysis temperature of 300oC by varying the pyrolysis times for 2 h, 5 h, and 10 h. The characterisation results showed that pyrolysis confirms a high content of carbon, minerals, graphitic structure, novel morphology and chemical characteristics attached to the biochar surface controlled by different pyrolysis durations. These properties were further enhanced by ball milling for 10 h. The results showed that ball milling enhanced the porosity, surface area, surface functional groups, visible light absorption, crystallinity, and carbon content, and these were accompanied by a reduction in the particle size and mineral impurities. The engineered biochar can be an important tool, with promising potential in novel composites for water purification and energy harvesting.