A Safe One-Pot Synthesis and Characterization of Epoxidized Moringa Oleifera Oil.

Global demand for epoxidized vegetable oil has been steadily growing. Epoxidized vegetable oils are typically produced using a two-pot synthesis process in which the oxidation and epoxidation reactions are carried out sequentially. This two-pot synthesis method, however, has a major drawback in industrialscale production, particularly when it comes to operational and process safety issues. A laboratory-scale one-pot synthesis method was attempted in this study with the aim to safely synthesize epoxidized Moringa Oleifera oil (eMOo) by avoiding the occurrence of undesired exothermic runaway reaction. The oil extracted from Moringa Oleifera oil seed kernel (MOo) was used as a starting component due to its high degree of unsaturation and also because the Moringa Oleifera plant can be freely grown in any soil conditions. Two parallel oxidation and epoxidation reactions were carried out simultaneously in this one-pot synthesis method to produce eMOo. The effect of five different mole ratios of MOo, acetic acid and hydrogen peroxide (1:1:1, 1:1:2, 1:1.5:2, 1:1.75:2 and 1:2:2, respectively) on reaction mechanism was investigated at the controlled temperature range of 43 - 55°C and reaction time of 0 - 120 min. The physicochemical properties of MOo as well as the oxirane oxygen content (OOC) of the resulting eMOo were characterized. In addition, GC-MS and FTIR analysis were performed to verify the molecular composition of MOo and also to identify the epoxy group of the resulting eMOo respectively. Among the five different mole ratios studied, the 1:1.5:2 mole ratio has the highest unsaturation conversion of 79.57% and OOC of 4.12%.

Disposal methods, health effects and emission regulations for sulfur hexafluoride and its by-products.

Sulfur hexafluoride (SF6) is the most potent greenhouse gas contributed by the power and semiconductor industries. The global emissions of gas in the past 10 years have increased tremendously due to lack of disposal routes. This was brought to 190 nations' attention in the Kyoto Protocol for the need of emission control measures to reduce its impacts of climate change and global warming. Various novel techniques have surfaced to tackle this issue, such as non-thermal plasma (NTP) which includes radio frequency plasma, microwave plasma, dielectric barrier discharge, and electron beam. The main by-products resulting from the decomposition of SF6 by these techniques are sulfur oxyfluorides, sulfur dioxide, hydrofluoric acid, and fluorine gas. This environmental and health effects as well as global emission of SF6 gas are considered a threat to humans and the climate, where modern disposal methods of contaminated SF6 gas and its by-products should replace the conventional approaches. Relevant government policies on the safety and disposal concern of SF6 gas are reviewed and challenges and further research directions for the disposal of SF6 gas are highlighted in this review article.