Arabica Coffee Pulp Cellulose: Isolation, Morphology, and its Capabilities to be Modified into Cellulose Nitrate

¹ Material Science and Engineering Research Group, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl.Ganesha 10, Bandung, 40132, Indonesia
² Energy Conversion Research Group, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia
³ Lightweight Structures Research Group, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia

^* Corresponding author: mardiyati@material.itb.ac.id

Abstract

Cellulose nitrate was a cellulose derivative applied in various applications, from plastics to solid propellants for military ammunition and rocketry. Environmental impact from using cotton linter or wood as a source of cellulose for cellulose nitrate industry promoting attempt to use agricultural waste as an alternative source of cellulose. Utilizing non-wood agricultural waste is also advantageous to reduce waste accumulation and give economical value. However, specific cellulose properties should also considered to achieve optimum cellulose derivation process into cellulose nitrate through nitration reaction. Coffee pulp waste had potential to be used as source of non-wood cellulose for its abundance, considerable fraction of cellulose content, low economical value, and unique cellulose morphology. In this study, the cellulose from the coffee pulp was isolated through sodium hydroxide and hydrogen peroxide bleaching method, which furthermore evaluated in terms of their morphology, physical properties, and its capabilities to be derived into cellulose nitrate. The result showed that coffee pulp cellulose has crystallinity and surface area around 59.63% and 0.5962 m²/g, respectively which is lower than cotton linter, suggesting advantageous properties for nitration reaction. Nitration to coffee pulp-based cellulose resulted in moderate nitrogen content cellulose nitrate which still suitable for non-military application.