Microstructure Modelling of Silica Bodies from Oil Palm Empty Fruit Bunch (OPEFB) Fibres

Abstract

Investigating the mechanical behaviour of silica bodies in oil palm empty fruit bunches (OPEFB) is important to improve the process of silica body removal. This study will assist in providing an understanding of the role of OPEFB as a bioresource material for the bioconversion process. The microstructure of silica bodies/protrusions on the OPEFB fibre surface was modelled using the finite element method, based on the information obtained from scanning electron microscopy (SEM). The effects of silica body geometry, possible anisotropy/orthotropy, and debonding between the interface of the silica body and OPEFB fibre were investigated. Agreements were observed between the results using both circular and spiked silica body models with different geometries and volume fractions. In addition, the cohesive debonding modelling results showed that once critical stress was activated, the stress-strain curve deviated from the nodebond model. The results also suggested that the value of cohesive energy should be between 0.5 kN/m and 4 kN/m.

Enhanced Delignification of Oil Palm Empty Fruit Bunch Fibers with in situ Fenton-oxidation

“…The oxidation process assisted with Fenton reagents showed some improvement of the delignification process along with the removal of silica bodies. Therefore, the removal of silica bodies could expose siliceous pathways and allow more exposure towards an amorphous region, which results in better hydrolysis performance (Omar et al 2014). In determining functional groups changes, the FTIR spectra of the raw EFB fibers was consistent with the content of lignocellulosic materials, including the presence of carbonyl and carboxyl, with the stretching of 1700 cm -1 and hydroxyl groups with a broad band of 3600 cm -1 to 3000 cm -1 (Fig.…”

Effect of Silica Bodies on the Mechanical Behaviour of Oil Palm Empty Fruit Bunch Fibres

“…In the first region where strain was less than about 0.03, damage within the microstructure of the fibre was thought to be minimal and the stress-strain curve showed linear elastic behaviour. For strains beyond 0.03, the plastic region was observed where Omar et al (2014), through a numerical work, suggested that the region is related to the debonding of the silica-body and OPEFB fibre interface. Finally, in the fracture region, fracture or total failure of OPMF was observed from the sudden drop of stress.…”

“…The shredded samples were then kept in a conditioned environment at -20 C prior to tensile tests and SEM analysis. Omar et al (2014). "Modelling of SiO2 bodies," BioResources 9(4), 7041-7058. 7043…”

“…Cross-section of an oil palm empty fruit bunch fibre (modified from Law et al 2007 andOmar et al 2014) The applications of OPEFB indicate the need to investigate the contribution of silica bodies to the strength of the fibres, especially on the surface and within the fibre cross section. Note that a preliminary work on the modelling of silica bodies and OPEFB fibre was reported recently by Omar et al (2014), whose work showed that silica bodies influenced the integrity of the fibres due to cohesive debonding. However, the work only considered the surface of the fibres without any consideration for experimental and cross section analysis.…”

“…Biocomposites, on the other hand, utilise OPEFB fibres as fillers mixed in a conventional resin (Khalid et al 2008) for products like automotive parts, furniture, and consumer merchandises. The surface of fibres containing silica bodies has been reported to provide more strength to the fibre-resin interface because the silica bodies restrict the bioresources.com Omar et al (2014). "Modelling of SiO2 bodies," BioResources 9(4), 7041-7058. 7042…”