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• Shale carbonate content influenced change in oil yield from shale to kerogen. • Higher S can explain higher reactivity for marine kerogens. • Lower S can explain greater polymerization of N in lacustrine kerogens. • Average aliphatic chain length was similar for both kerogen liquids. • More substituted aromatics in kerogen hydrogen liquids than in nitrogen liquids. The reactivity of kerogens from two different types of oil shales, marine Attrat oil shale from Jordan (type II kerogen, high sulfur) and lacustrine Colorado from USA (type I kerogen, low sulfur) has been studied. The kerogens were obtained using the NaOH/HCl demineralization method. The reaction products from the kerogens were compared with those from the raw shales. The reactivity of Attrat and Colorado kerogens was measured using sealed autoclaves at 355 and 390 °C for 1–5 h under N 2 or H 2 pressure. Attrat kerogen showed a higher conversion than Colorado kerogen, probably due to its high sulfur content. Except for Colorado at 390 °C under N 2 , kerogen was more reactive than the raw shale. The reactions under H 2 produced higher oil yields for Attrat raw shale and kerogen when compared to their reactions under N 2. The reactions of Colorado under H 2 showed the opposite effect in most cases. The yields of CH 2 Cl 2 -solubles + water + hydrocarbon gas + sulphide gas increased with temperature whereas those of asphaltene and asphaltol decreased. CH 2 Cl 2 -solubles from both kerogens showed high atomic H/C ratios, with high sulphur content (Attrat) and nitrogen content (Colorado), as expected from the properties of the original kerogens. The proton nuclear magnetic resonance (1H NMR) indicated the highly aliphatic character of both CH 2 Cl 2 -solubles and, in contrast to what was observed for the raw oil shales, no significant change when H 2 was substituted for N 2. The aromaticity of CH 2 Cl 2 -solubles was higher for Attrat than Colorado (0.4 vs 0.3) as for the original kerogens, and the aromatic rings in both cases were heavily substituted. The gas chromatography-mass spectrometry (GC–MS) for both kerogen reaction products indicated highly aliphatic character; Attrat kerogen reaction products were distinguished by the presence of substituted thiophenes and benzothiophenes while these compounds could not be detected in Colorado kerogen reaction products. The marked differences between the reactions of the two kerogens did not appear to be due to effects of marine/lacustrine character, as such, but rather to the high S content of Attrat kerogen. [ABSTRACT FROM AUTHOR]

Due to the high cost of bioplastic production, sesame wastewater, generated from the sesame seed hulling process, was investigated to be used as inexpensive and renewable carbon source for the production of biodegradable polyhydroxyalkanoate (PHA) by extreme Haloferax mediterranei. The sesame wastewater (SWW) was hydrolyzed using different concentrations of hydrochloric acid (0.4. 1.00 and 2.00 M) at different period of times (15, 60 and 90 min). The concentration of salt (NaCl) and nitrogen source (NH 4 Cl and yeast) required for H. mediterranei cells growth and the accumulation of PHA biopolymer was optimized. A maximum 0.53 g/L concentration of PHA was achieved when the SWW extract media was supplemented with 100 g/L NaCl and 6.0 g/L yeast extract. The cultivation was scaled-up using sequencing batch reactor (SBR) fermentation under non-sterile conditions. The SBR results showed that SWW needs an auxiliary carbon source to obtain high PHA production. Consequently, the system fed with SWW and glucose produced higher PHA (20.9 g/L) than the system fed with SWW. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel extraction of oil from a Jordanian oil shale using supercritical propane with a co-solvent. • High oil yields achieved at very low temperature. • Above the critical temperature of propane (100 °C), higher yields obtained at high pressure. • The oil had more oxygen and less sulfur than high-temperature oil. • Oil was easily hydrogenated to reduce sulfur and oxygen contents dramatically. The only method currently used for producing oil from oil shale is high temperature retorting, which is wasteful of energy and gives oil with a high content of heavy oil. The novel method of extraction used in this study, involving supercritical propane with tetrahydrofuran as a co-solvent, solves the problem of the high cost of producing oil by conventional high temperature retorting. El-Lajjun oil shale from Jordan was used to evaluate the reaction yield and the characteristics of the product. At supercritical propane temperature and pressure (100 °C and 4.3 MPa), the yield was high and comparable to that for the conventional retorting method (>350 °C). As the temperature increased to 200 °C, the oil yield increased with pressure. The oil obtained was high in aliphatic hydrocarbons but with significant amounts of ethers, some carbonyls and sulfur-oxygen compounds. Hydrodeoxygenation and hydrodesulfurization of the produced oils using NiMo-Al-SBA-15 catalysts significantly enhanced the quality of the oil by decreasing the oxygen and sulfur contents and increasing the aliphatic and diesel fractions. This work leads to an enduring breakthrough technology that substantially reduces costs, waste, energy and the environmental impact of using oil shale as a raw material for liquid fuel production using Green Technology. Recovery of THF is high (>95%) and re-use of THF and propane would be essential for commercial application. [ABSTRACT FROM AUTHOR]

The increase in energy demand, especially in Jordan, has encouraged researchers to consider alternative sources of energy, such as biofuel production from agricultural waste. For this study, Jordanian corn leaf waste was characterized by ultimate and proximate analysis, TGA, FTIR and solid state 13C NMR. The waste showed high volatile matter, high atomic H/C ratio and high O content. The corn leaf waste contained 32.1 wt% cellulose, 18.1 wt% hemicelluloses and 11.9 wt% lignin. The FTIR and 13C NMR spectrums showed high concentrations of aliphatic and carbonyl carbon. The corn leaf waste was pyrolysed in a temperature range of 300–450 °C under a constant flow rate of nitrogen. Higher oil yield was obtained at pyrolysis temperature of 450 °C. The gas yield and higher heating value of the product increased as the temperature increased, whereas the water content decreased. The biofuels were rich in carbon and had a high oxygen content, which decreased as the temperature increased. The 1H NMR confirmed the markedly aliphatic character of the biofuel. The GC-MS for the biofuel indicated the presence of hydrocarbon series, large amounts of oxygenated compounds and a few nitrogen and sulfur compounds. The simulated distillation showed a high proportion of diesel fraction (57–73%). Image 1 • Detailed structural characterization of corn leaf waste is given. • The corn leaf waste was pyrolysed in 300–450 °C under nitrogen. • The biofuel contained only 8–18% aromatic protons. • Biofuel O content fell from 27% (<300 °C biofuel) to 18% (400–450 °C biofuel). • Important identified biofuel compounds: phenols, neophytadiene and acids. [ABSTRACT FROM AUTHOR]