Olefins and Fuels From Frying Palm Oil Through Pyrolysis

Thermal Treatment under Vacuum for Obtaining a Quenchant from Rapeseed Oil

“…The iodine number of bio-oils is close to that of the raw (5.8 + max. 0.2 g I 2 /100 g) sample, in contrast with the bio-oils obtained from the pyrolysis at atmospheric pressure and higher temperature [23][24][25] in which iodine number increased by up to 2.5 units. This means that, at these relatively low process temperatures, dehydrogenation of the heaviest part in raw oil was minimal, and chemical modifications were minimal in general.…”

“…The bio-oil quantities and yields after pyrolysis at 300 • C, 310 • C, 320 • C and 375 • C are found in Table 2. In a vacuum, the pyrolysis oil yield decreases with process temperature increasing, as well as at atmospheric pressure [23] or in the presence of an inert gas [24,25], and in the presence of a catalyst [26,27]. Decreasing of the liquid yield from 87% to 45% over a merely 20 • C range of temperature is influenced by the low pressure strongly favoring the decomposition to gaseous products.…”

“…Surprisingly, the rapeseed oil showed the best result even if it was more viscous and had the lowest cooling rate at 700 • C. However, differences in hardness were small, as differences in their characteristics were small (see Table 3), with every oil performing well. Also, there is a great advantage in using the pyrolytic bio-oil since, during the pyrolysis, yields between 13-55% are obtained in products with added value such as gaseous olefins, kerosene-like and diesel-like fractions [23,24] which can be recovered from the vacuum system in the industrial unit.…”

Drop-in biofuels production from microalgae to hydrocarbons: Microalgal cultivation and harvesting, conversion pathways, economics and prospects for aviation

“…The feasibility of applying this technology in producing renewable fuels from lipid-based feedstock has been widely studied [164,[166][167][168][169][170][171][172][173]. The detailed reaction mechanisms are difficult to characterize because of the complexity and multiplicity of reaction pathways and products, but they are influenced by reaction conditions, such as temperature, residence time, and the presence of other gases in the system [174,175]. A primary cracking has been proposed where fatty acids are formed during the thermal cracking of triglycerides by breakdown of C-O bonds between the portion that corresponds to the glycerol and the rest of the molecule, followed by a secondary cracking where fatty acids break down into smaller hydrocarbons [176,177].…”

“…Reaction temperature, typically leads to an increase in gas yield due to over-cracking and an increase in solid formation due to polymerization and/or aromatization as temperature rises; as a consequence, liquid yield drops [136,168,175]. In contrast, an increase in the residence time at an optimal temperature does not necessarily lead to over-cracking, but to a polymerization of low molecular weight species into liquid [168].…”