ABSTRACT As consumer demand shifts towards more sustainable and nontoxic alternatives, the candle industry is exploring unconventional bio‐based and recycled materials as substitutes for paraffin. Four raw materials, that is rice bran wax (RBW), sugarcane wax (SCW), hydrogenated rapeseed oil (HRO), and waste cooking oil (WCO) were assessed based on their thermal behavior and combustion performance. A mixture design approach was applied to evaluate the effects of each component and their interactions, using combustion time as the primary response. Among the nine formulations tested, only two met the targeted combustion criteria. SCW showed poor compatibility, reducing the combustion time probably due to its broad melting profile and complex composition. In contrast, small amounts of RBW and WCO demonstrated promising complementary effects: RBW contributed to improve stability, while WCO enhanced combustion when combined. This study highlighted the effectiveness of mixture design as a useful tool as it enabled rapid screening of components and evaluating material combinations to improve combustion performance.
Daoufa et al. (Tue,) studied this question.