Dehydration and desalination of oils using supercritical carbon dioxide

Current status and prospects of demetallization of heavy petroleum feedstock (Review)

“…Thus, research and development works on various modifications of desali nation processes aimed to increase the recovery of metals [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] are of great current importance.…”

“…6 2015 Samedova et al [34][35][36] showed the feasibility of desalting, dewatering, deasphalting, and demetalliz ing of crude oils and their heavy residues using super critical carbon dioxide (SC CO 2 ) as a solvent (extract ing agent). A new oil cleaning technology to remove water, salts, solids, and metals using SC CO 2 was implemented on a pilot unit at the pilot plant of the Institute of Petrochemical Processes, National Acad emy of Sciences of Azerbaijan.…”

“…This technology allows not only for the removal of water, dissolved salts, and suspended solids from oil, but also its deasphalting and demetallization. Supercritical fluid extraction of oil samples results in their dehydration (to 0.5% or even complete absence of water), desalting (from 40.5-54.9 mg of NaCl/L to zero level), and reduction in the solids content from 0.0348-0.0704 to 0.0102-0.0169% [35]. Simultaneously, the physicochemical properties of oils are altered, namely, the density and kinematic viscosity of the samples are decreased by the extraction.…”

A Review of the Unconventional Methods Used for the Demetallization of Petroleum Fractions over the Past Decade

“…Crude oil contains traces of up to 1000 ppm of various metals such as vanadium (V), nickel (Ni), cobalt (Co), copper (Cu), and arsenic (As). − Metals are generally concentrated in the higher boiling fractions of crude oil (above 540 °C or 1000 °F). , Among the metals, Ni and V are the most abundant in natural petroleum, of which V constitutes ∼80% of metal concentration. ,, Ni is generally found in the +2 valence state . Both Ni and V are found as porphyrinic structures and all vanadium present is reportedly porphyrinic. , Reportedly, all of the vanadium detected by very high-resolution mass spectra techniques was associated with porphyrins. , The relative amount of metals (in all forms) to other major impurities present in crude is shown in Table .…”

“…Calcium and magnesium chlorides dissolved in oil get hydrolyzed when subjected to temperatures of 160–180 °C. HCl formed due to this hydrolysis causes excessive corrosion of equipment . The presence of iron, copper, vanadium, and nickel causes an increase in the level of coke deposits affecting the activity of the cracking catalyst …”