Based on the DPPH radical scavenging activity test results, Irganox L06 and BHT demonstrated the highest potential as antioxidants.
The heat test results highlighted Irganox L101, Irganox L109, and Irganox L06 as the most effective antioxidants. The results from the oxygen and heat tests further supported these findings, particularly endorsing the use of Irganox L101 and Irganox L06.
In summary, taking into account both the DPPH% and the stress test outcomes, Irganox L06 and Irganox L101 emerge as the most suitable antioxidant additives for white oils, with Irganox L06 being a phenolic antioxidant and Irganox L101 an aminic one.
The effect of antioxidant concentration (ranging from 0.1% to 0.8%) on ΔTAN and V/V0 values was found to be statistically insignificant for these antioxidants.. Consequently, the lowest concentration tested (0.1%) is recommended for use in white oils to minimise the cost of additives.
For situations that demand higher antioxidant capacity, the highest concentration tested (0.8%) of Irganox L101 is recommended, as DPPH% showed a linear increase with concentration up to this point. In the case of Irganox L06, a concentration of 0.3% is recommended, as the antioxidant activity plateaus beyond this level.
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