Recovery of Green and Healthy Antioxidant from Palm Oil Mill Waste

Antioxidants are substances that may protect our cells against the effects of free radicals. Antioxidant substances include beta-carotene, vitamin A, vitamin C and vitamin E. Carotenes possess anti-cancer properties for preventing certain types of cancer diseases, enhance immunity, prevent blindness and skin disorders, as well as to protect against toxins, colds, flu and infections.

The benefits of carotenes are shown in Figure 1 (download file). World Health Organization considers vitamin A deficiency to be a public health problem in more than half of all countries and particular beta-carotene is the most important vitamin A precursor in human nutrition.

Carotenes can be found in yellow, orange, and green leafy fruits and vegetables. These can be carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantalouporangee, , winter squash and etc. as shown in Figure 2 (Download file). The demand for carotenes is high but carotenes preparations derived from extraction of vegetables are expensive due to high cost of raw materials. Since palm oil mills generate abundance of palm oil mill effluent (POME), carotenes can be recovered from the waste. POME are predominantly organic in nature and are highly polluting as shown in Figure 3.

Malaysia is basically an agricultural country and the major polluting industrial effluents have been from agro-based industries, which is palm oil industry. About 3 tonnes of POME was produced for every tonne of oil extracted in an oil mill. In 2007 alone, 15.8 milllion tonnes of crude palm oil (CPO) have been produced, resulting in 47.4 million tonnes of POME. 284,000 tonnes of oil can be extracted from POME along with recovery of 140,000 kg of carotenes. If the POME is discharged untreated, for 47.4 million tonnes of POME, the amount of biochemical oxygen demand (BOD) produced is 1.185 million tonnes which is equivalent to the waste generated by 64,931,500 citizens of the country (assuming each citizen produce 18.25 kg of BOD every year).

The global market for carotenoids is at USD 1 billion which rise annually by 2.9 per cent. The market value of natural carotenes is about RM6000 per kg. By treating POME accordingly, a 60 tonne FFB/hr palm oil mill can generate RM 5.52 M per year from carotenes recovery and for whole Malaysia the gross income generate from recovery of carotenes is about RM 852 M per year (Figure 4). This creates an opportunity for the palm oil millers to have a side income.

Carotenes can be recovered from POME, a readily available raw material and it is a breakthrough in POME wastewater treatment as no similar invention has been reported. Through this research, a downstream processing technology for converting POME into value added natural product, carotene is developed. Organic-aqueous extraction is used to retrieve oil from POME and adsorption chromatography approach is further adopted to recover the carotenes contained in the oil. This is in line with the world awareness towards creating a clean and healthy environment by using green technology, where waste is changed into wealth. Figure 5 shows the extraction of oil and carotenes recovery process.

This research creates a new and cheap source to attain carotenes. The utilization and reuse of agricultural waste into commercial value added product indirectly solve the environmental problem. Carotenes can be applicable as natural compounds in food, cosmetic and pharmaceutical industries.

The whole process is a sustainable development for palm oil industries (Figure 6) where the pollution potential of POME which is oil and grease are removed for carotenes recovery and the remaining POME is water and solids which are non-hazardous. The remaining solids can be easily converted to organic fertilizer and the water can be recycled back for the palm oil mill usage. The organic fertilizer can be used for plantation and provides many benefits to the cultivation of oil palm.

In conclusion, this research changes waste into gold by incorporating the zero-discharge concept. The wastes produced are converted into products with high commercial values. It also gives positive impact to the public by solving environmental problem besides giving value added products.