The Effect of grain size on the complex permittivity of Oil Palm Empty Fruit Bunch Fiber for Microwave Application

Ismail Ibrahim Lakin, Rabi’u Abubakar Tafida , Nicodemus Kure, Ibrahim Abubakar Alhaji

Keywords: Oil palm fiber; Permittivity; Microwave absorption; X-band frequency

Abstract

Oil palm empty fruit bunch (OPEFB) fiber, a waste product from oil palm mill is 100% biodegradable, environmentally friendly, and cheap was prepared and characterized for possible microwave absorbing material by determining its permittivity for fiber size and frequency. The dielectric properties were investigated by the use of open-ended coaxial (OEC) probe at microwave frequency 8-12 GHz range. The results showed that the dielectric properties of the OPEFB fiber material can be influenced by changing its particle size (100, 200, 300, 400, and 500 µm). The dielectric constant (  and loss factor ( increased as the particle size of the fiber decreased. The  values for the lowest and highest fiber size (100 and 500 µm) were found to be 3.13 and 2.81 while  values were 0.38 and 0.26 respectively. Improved complex permittivity with reduced particle size demonstrated their suitability for making composites that could attenuate microwaves within the X-band frequency range.