OPDC NATURAL COMPOSITE POLYMER FROM PALM BIOMASS
Each year, Malaysia produces millions of tonnes of oil palm biomass such as oil palm trunks (OPT), oil palm fronds (OPF), oil palm empty fruit bunches (OPEFB), mesocarp fiber (MS), palm kernel shell (PKS), palm oil mill effluent (POME) and more recently oil palm decanter cake (OPDC).
The increasing production of OPDC is due to more installation of decanting machine in the palm oil mills. The purpose of installing decanter machine is for the removal of fine suspended solid and recovery of residual crude palm oil from the sludge fraction of the vertical clarification tank (VCT) underflow stream.
The current most popular uses of OPDC are as animal and fish feed and also for compost production. In the long run, this is not a sustainable practice to use OPDC because of lower quality and price and therefore the palm industry is urgently looking for a more sustainable utilization of OPDC. Owing to its special physical and chemical properties such as fine powder form and high in cellulose content, OPDC can be used as a natural filler to produce natural polymer composite (NPC).
NPC is a type of material made by combining natural fibre and polymer and it has a very wide modern application in many industries such as composite material, furniture, automobile, building, construction and petrochemicals. Usually agricultural wastes are suitable natural filler because of its low production cost, biodegradable, low energy consumption, low density, safe handling, renewable and environmental friendly.
Therefore the objectives of this innovation is to produce NPC from OPDC material recovered from palm oil mill waste and then determine its mechanical and physical properties such as elasticity, stiffness, tensile strength and water absorption rate. Prior to NPC development, the remaining oil in OPDC was removed by using a hexane soxhlet extraction method.
The oil-free OPDC was then dried and ground to a fine powder form and sieved to less than 100 microns. For the NPC production, the material was fabricated using remoulding method where mixture of OPDC and polymer (polypropylene - PP) were combined at 95% PP and 5% OPDC using twin-screw extruder machine (PRISM, USA).
For the physical and mechanical testing, Universal Testing Machine (INSTRON, England) was used. In general, the results showed that the elasticity of OPDC-NPC was 2231 MPa, stiffness was 30 MPa and tensile strength 32 MPa. These results were comparable with other natural fibre such as jute, coir, palm fibre and OPEFB. By varying the OPPDC content from 5% to 15%, the stiffness improved to 43 MPa. However, for the water absorption test, the fibre required further improving.
This is due to hydrophilicity nature of OPDC material. This [properties can be enhanced by chemical treatment to become more hydrophobic. In conclusion, this study provides a better understanding of OPDC characteristic, the relationship between OPDC natural fibre content and the mechanical and physical properties of OPDC-NPC and therefore it can be concluded that OPDC is a potential material for NPC production. The future challenges would be on improving the colour and odour by lignin removal and improving the hydrophobicity of OPDC by the chemical surface modification method.
Alawi Bin Hj Sulaiman
Muhammad Aqif Bin Adam
Faculty of Plantation & Agrotechnology
UiTM Shah Alam
Email : [email protected]