WHILE palm oil remains the most efficient oil crop globally, it remains entangled in concerns regarding sustainability, biodiversity, health risks, and more. While some issues may be misconceptions, others are genuine challenges, such as the presence of process contaminants like 3-MCPDE (3-monochloropropane-1,2-diol) and GE (Glycidyl esters).

Contaminants from the process

3-MCPDE and GE are contaminants that can be found in vegetable oils and food items derived from these oils. They are byproducts that may arise during the refining process of oils, where high temperatures are utilized to meet quality and safety standards. These process contaminants could possible and probable have carcinogenic effects on humans, respectively. Notably, refined palm oil tends to have the highest concentrations of 3-MCPDE.

Thanks to the research conducted by various parties, the industry has identified the sources of precursors responsible for the formation of 3-MCPDE and GE. Chlorides, along with diacylglycerols and monoacylglycerols, which are linked to free fatty acid levels in crude palm oil (CPO), are the primary precursors for 3-MCPDE and GE, respectively. While there are several options to mitigate the formation of these contaminants, spanning from plantations to mills and refineries, palm oil millers play a crucial role in this process.

The questionable nature of secondary oil recycling

Across different processing units in palm oil mills, unavoidable oil losses occur. Some millers choose to recycle these oils to improve process efficiency. While this practice is well-intentioned, it carries the risk of reintroducing poor-quality secondary oil back into CPO, potentially contaminating it with high levels of chlorine and free fatty acid.

Additionally, some millers are apprehensive that if they do not recycle such oil, it will be disposed of as waste oil and left in effluent ponds as palm oil mill effluent oil (POME oil), thereby making it worthless and significantly affecting their income. For instance, in a typical oil mill with a processing capacity of 45 tonnes per hour, the potential annual revenue loss could exceed 4 million Malaysian Ringgit. This may explain why the Malaysian Palm Oil Board (MPOB) has decided to postpone the planned implementation of Licensing Conditions for 3-MCPDE and GE, originally scheduled for 1 January 2023, to 1 January 2026.

Repurposing secondary oil for higher value products

However, the situation has evolved since then. POME oil now holds the potential to be repurposed into higher-value products. It can serve as feedstock for the production of renewable diesel or hydrotreated vegetable oil. Presently, numerous renewable diesel producers seek POME oil that carries International

Sustainability and Carbon Certification (ISCC) due to its favourable attributes. Certified POME oil is regarded as emitting zero greenhouse gases at its collection source and qualifies for double counting toward blending targets in the European Union. Depending on market dynamics, some certified POME oil has been sold at prices close to that of CPO.

Certainly, there are additional expenses associated with obtaining ISCC certification for POME oil, including audits, documentation, training, and potential infrastructure enhancements to meet certification criteria. However, the return on investment for such endeavour typically materializes within a few months for a standard operational oil mill. Moreover, palm oil mills equipped with facilities for empty fruit bunches (EFB) pressing and pressed palm fibers (PPF) oil recovery can also market their EFB and PPF oil for similar purposes and values as POME oil. This enhances the attractiveness of ISCC investments.

Rethinking for the future

With such lucrative options now available, MPOB may reconsider not only preponing the Licensing Conditions for 3-MCPDE and GE but also introducing stricter standards for CPO. The current specifications for CPO, widely used in trade between millers and refiners, have remained unchanged for decades. Therefore, this could be an opportune moment to revise the standards to include more parameters such as chloride content, while also making existing parameters such as free fatty acids level more stringent.

The national palm oil extraction rate could potentially be impacted if the recycling of secondary oil to CPO is prohibited. To tackle this issue, MPOB could contemplate requiring millers to report both CPO and secondary oil production separately, and then consider them collectively in calculating the oil extraction rate with appropriate classification. This approach would also enable MPOB to effectively monitor mills to prevent any deliberate production of excessive secondary oil.

It's time to take action

Repurposing secondary oil for high-value feedstock in renewable diesel production would offer dual benefits by not only ensuring the quality of CPO but also generating additional revenue streams for millers. Thus, are we ready to elevate the quality standards of Malaysian CPO and position it as a superior product that meets international standards for 3-MCPDE and GE?


* Eur Ing Hong Wai Onn, a chartered engineer and chartered environmentalist, is a Fellow of the Institution of Chemical Engineers, the Royal Society of Chemistry, and the Malaysian Institute of Management. He is also the author of “A Chemical Engineer in the Palm Oil Milling Industry”

** The views and opinions expressed in this article are those of the author(s) and do not necessarily reflect the position of Astro AWANI.