The precipitation of asphaltenes in two Mexican crude oils was measured using a combination of high-pressure isothermal expansion and atmospheric titration with nalkanes. Experiments were carried out from the liveand tank-oil type of samples of the same crude oils. For the oils investigated, compositional data, precipitation phase diagrams, and bubble point pressures are reported. A theoretical...

Quantitative analysis of separated carboxylic acid fractions of 33 crude oils from the UK, Italy and California, showed that the carboxylic acid fraction is a major factor responsible for the acidity in these oils. It was apparent that biodegradation is the main process that produces high concentrations of carboxylic acids in these crude oils with the extent of biodegradation, as measured from ...

The distillation unit is one of the main units in refning companies, and it serves as the mother unit in any refnery with any degree of complexity. The optimization of this unit can increase productivity. In this study, the vacuum distillation unit of a refnery was selected as the case study. The shares of different expenses of this unit were clarifed using a novel material flow cost accoun...

considerable amounts of different pollutants, especially crude oils, are present in the persian gulf and its northern region, so biomonitoring the effect of these pollutants on its biota is necessary. ethoxyresorufin o-deethylase (erod), gluthathione s-transferase (gst) and catalase (cat) activity were measured from biochemical level in the gills of mudskipper periophthalmus waltoni collected f...

Bioassays for carcinogenicity of various primary processing products (crude oils or tars) and commercial products obtained from Estorian oil shale have been carried out since 1951. The products (undiluted or diluted) were painted twice weekly 50 times on the interscapular area of the skin of random-bred or CC57Br mice. The products processed at high temperatures have a higher carcinogenic activ...