THE ABILITY OF SAWDUST (WOOD) DERIVED ACTIVATED CARBON TO BLEACH PALM OIL AND SOYABEAN OIL (original) (raw)

The activated carbon used in this study was derived from sawdust (wood), so it is referred to as activated sawdust (wood), whereas the activated carbon derived from coal is referred to as activated coal. Activated carbon is typically derived from waste products such as coconut husks, waste from paper mills, walnut shell, apricot stone, etc.; such that these bulk sources are converted into charcoal before being activated. Activation of carbon is the process of treating the carbon to open an enormous number of pores in the 1.2-20nanometer diameter range. Chemical activation was preferably used due to its shorter production time and lower temperature required to produce activated carbon. During chemical activation, the source material is impregnated with certain chemicals typically an acid, a strong base or a salt (phosphoric acid, potassium hydroxide, calcium chloride and zinc chloride) such that the raw material is carbonized at a low temperature, usually 450 0 C-900 0 C. This process results in a very large surface area that is about 600-1200 square feet per grams depending on the source material. Natural coal was carbonized and activated to obtain a high degree of degummed and less resinous oils and oils freed from impurities.The wood sawdust was chemically activated after being dried, and the process involved weighing the sample and mixing it with 100mls of 35% phosphoric acid in an oven that ran between 600°C and 800°C for about 4 hours. The sample was then put through filteration by adding water to it, which was done around six times until a pH of 5 or 6 was reached, indicating a decrease in the amount of acid present in the sample. Two samples of oil (palm oil and soyabean oil) were also subjected to the adsorption (bleaching) process which involves the removal of pollutants like free fatty acids (FFAS), phosphatides, heavy metals, oxidized products, and color pigments using activated carbon generated or created from sawdust (wood), measured in the range of 0.5g, 1.0g, 1.5g, 2.0g, 2.5g and 3.0g, respectively. Bleaching is required not only because fat with a light color conveys a sense of purity, but also because the color of the fat can affect how food will look when it is cooked and, more importantly, because the pigment it contains can affect the flavor and stability of the fat and the food it is used to make. The different oil samples were degummed using a 500 ml volumetric flask and hot water (100 0 C), and the process was repeated until clear water was seen below the oil layer in the separating funnel. The degummed oils were then heated at 80 0 C for around 10 minutes to neutralize them. In a similar manner, hot degummed oils were treated with around 10 ml of NaOH and 6g of NaCl. Water was then added to wash off the soap that had developed in the neutralized oil, and this process was repeated until the oil was soap-free. An ultraviolet (UV) spectrophotometer with a wavelength of 460 nm was used to test the absorbance and concentration of the various types of neutralized oils. The Langmuir isotherm equation, which has the following formula: Ce/qc = 1.Ce/Q o + 1/ bQ o , was used to determine the equilibrium concentration, values for Ce/qc, b, and slopes for palm oil and soybean oil. Q o is the adsorption capacity, and b is the Langmuir constant. The results obtained