Table 5
Dielectric properties of some known solids compared to oil palm biomass.
Materials ε
r tan References
Biomass and bioresource products
Wood 2.3 0.11 Torgovnikov (1993)
Fir plywood
≈1.5 0.01–0.05 Torgovnikov (1993)
Particle board
≈2.5 0.1–1.0 Torgovnikov (1993)
Bark (Aspen)
≈9.4 0.22 Torgovnikov (1993)
Bark (Pine)
≈4.4 0.18 Torgovnikov (1993)
Oil palm fiber
≈2.0 0.08 This study
Oil palm shell
≈2.7 0.13 This study
EFB 6.4 0.3 Omar et al. (2011)
OPS char
≈2.8 0.08 This study
EFB char 3.5 0.13 Omar et al. (2011)
Plastics and rubbers
Polypropylene
≈2.2 0.003–0.004 Eccosorb (2011)
Polyethylene
≈2.3 0.001–0.002 Eccosorb (2011)
Teflon
≈2.1 0.001–0.002 Eccosorb (2011)
Natural rubber
≈2.1 0.002–0.005 Eccosorb (2011)
Glass
Fused quartz
≈3.0 0.001–0.002 Eccosorb (2011)
Fused silica
≈3.0 0.002–0.003 Eccosorb (2011)
Borosilicate glass
≈4.0 0.001–0.002 Eccosorb (2011)
Pyrex glass
≈4.0 0.005–0.01 Eccosorb (2011)
Metals and others
Zinc oxide
≈3.0 0.1–1.0 Eccosorb (2011)
Mica
≈5.0 0.003–0.004 Eccosorb (2011)
SiC 10.8 0.0324 Eccosorb (2011)