Bio-oil is chemically and thermally unstable during storage and transportation. For that reason, it is necessary to evaluate the changes in the properties (chemical and physical) of bio-oil during storage to understand its chemical instability, which will further assist researchers in stabilization strategies. This paper describes the evaluation of an accelerated aging process on the physical and chemical properties of bio-oil from fast pyrolysis of ash and birch woods using two different pyrolyzers, a pilot scale (auger) and lab scale (tube furnace), respectively. The produced oils (freshly made) were aged at 80°C over different periods (1, 3, and 7 days) in sealed nitrogen-purged Nalgene vessels. Fresh oil was analyzed alongside aged oils. Bio-oils were characterized by viscometer, Karl Fischer titration (H 2 O), pyrolysis−gas chromatography/mass spectrometry (GC/MS), thermogravimetric analysis (TGA), photo-microscopy, 13 C nuclear magnetic resonance (NMR), and Fourier transform infrared spectroscopy (FTIR). The water content, viscosity, decomposition temperature (TGA) and ash content levels in bio-oil samples all increased as the aging period lengthened. GC/MS analysis showed a major reduction in GC-analyzable components. The mass of residue remaining after pyrolysis−GC/MS increased, and the structures of pyrolysis products of this non-volatile residue along with NMR and FTIR data suggest the following aging processes; some of the reactive compounds undergo polymerization or reaction with other compounds, including olefins, alcohols, and aldehydes. Some possible reaction mechanisms are given. The oils remained as a single phase throughout the initial study period; however, on day 7, a clear phase separation was observed by photo-microscopy.

Concentrations of Cd, Cu, Fe, Pb, and Zn were measured in the samples of street dust and surface roadside soil before Jordan switched to unleaded fuel usage. The samples were collected from Petra, the most tourist-attractive site in Jordan. The samples were analyzed for heavy metals by atomic absorption spectrophotometry. Our results show that the distribution of metals in the soil samples is affected by wind direction in the investigated area. The highest level of metals was found in the eastern parts of the roads due to the westerly-dominant wind in the studied area. The contamination levels of metals decrease as the distance from the edge of the road increases. In the roadside soil samples, the means for the concentrations of the metals at 1 m from the east side of the main road are 1.0, 19.1, 3791.4, 177.0, and 129.0 mg kg for Cd, Cu, Fe, Pb, and Zn, respectively. In the samples of street dust, the means of the concentrations of the metals in the investigated area are 9.7, 11.8, 4694.4, 31.6, and 24.8 mg kg for Cd, Cu, Fe, Pb, and Zn, respectively. In conclusion, the lithogenic origins (traffic emissions) are responsible for the diffusion of these metals in the studied region.

Direct infusion-electrospray ionization (ESI)-Ion-Trap MS and ESI-Ion-Trap MS2 were used for direct analysis of bio-oil from forest residue and reference bio-oils from cellulose and hardwood lignin. It was found that the bio-oil concentration and mode of MS analysis are important parameters in obtaining reproducible and structurally informative data. In order to study sensitivity and selectivity with ESI-Ion-Trap MS, a selection of model compounds were studied with and without dopants. Dopants included NaCl, formic acid and NH4Cl in positive ion mode and NaOH and NH4Cl in negative ion mode. NH4Cl addition can be used to distinguish carbohydrate-derived products from other bio-oil components. NaOH and NaCl additives produced the highest peak intensities in negative ion mode as deprotonated adducts and in positive mode as sodiated adducts, respectively. ESI-MS2 was used successfully for confirmation of individual target ions such as levoglucosan and cellobiosan, as well for some structural products of lignin. Simple bio-oil fractionation into hydrophilic and hydrophobic components provided less complex and more interpretive ion spectra.

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Background The chemical composition of Handal (Citrullus colocynthis L.) seed oil cultivated in Jordan deserts was characterized, and its bioactivity was evaluated. Methods The oil was extracted from the grinded seeds in 500 ml Soxhlet extractor for 24 hr using n‐hexane, and the recovered fatty acids were methylated with methanolic‐HCL. The fatty acid methyl esters (FAMEs) composition was analyzed using GC‐MS and GC‐FID. The anticancer activity associated with the oil was assessed against colon cancer cell lines (Caco‐2 and HCT‐116) and compared to its cytotoxicity on the human skin fibroblast. Multivariate analysis was used to determine relationship of the fatty acid composition with that of the anticancer activity. Results The results demonstrated that fatty acid composition of Citrullus colocynthis seed oil chiefly contains Linoleic acid, denoted as C18:2n6 (75%), followed by Palmitic acid C16:0 (8%), Stearic acid C18:0 (5%), and Oleic acid C18:1n9 (9%). It is demonstrated as an excellent source of essential fatty acids omega‐6 (e.g., Linoleic acid), whereas omega‐3 (e.g., α‐Linolenic acid) and hydroxy polyunsaturated fatty acids are found at small level. Interestingly, the oil exhibited reasonable anticancer effects against colorectal cancer cell lines with IC50 values varying between 4 and 7 mg/ml. The correlation test revealed a relationship between the fatty acid composition and the effectiveness on treatments. Conclusions Handal plant from Jordan appears to have very high level of Linoleic acid compared to other oils measured in different geographic locations and that there appears to be some anticancer activities associated with the fatty acid content of Handal seed oil.