Monitoring the behaviour and fate of nickel and vanadium complexes during vacuum residue hydrotreatment and fraction separation

The role of metalloporphyrins on the physical-chemical properties of petroleum fluids

“…Size exclusion microchromatography with high-resolution inductively coupled plasma mass spectrometric detection technique (ICP-MS) has demonstrated the trapping of metalloporphyrins (MP) by asphaltene nanoaggregates [16]. Caumette et al [37] and Barbier et al [38] have shown using the same technique that nickel and vanadium can be found trapped in asphaltene aggregates with a mass range between 200 and 40,000 Da, in dif-ferent fractions with proportions that depends on the geographical or geochemical origin of the crude oil under study. More particularly, electron-spin resonance (ESR) quantitatively measured levels of the paramagnetic vanadyl ions VO 2+ and organic radicals trapped in crude oils with and without asphaltene [16].…”

Development of a chromatographic methodology for the separation and quantification of V, Ni and S compounds in petroleum products

“…Caumette et al [20,21] developed a methodology to separate and speciate Ni and V compounds in crude oils.The resolution achieved using their technique allowed the discrimination of at least three classes of Ni and V species containing varying proportions of the metals as a function of the origin of the crude oil, the crude oil fraction (asphaltenes vs.maltenes) and the dilution factor. Even more recently, another group Wandekoken et all [22] developed a methodology for separation of organic vanadyl 5 compounds in crude oil using fractionation by preparative liquid chromatography using as eluent different mobile phases, in their results all the V is linked to porphyrin structure, discarding the existence of non porphyrinics Vanadium compounds and a similar distribution of the vanadyl porphyrins between polar and non polar fractions.…”

Asphaltenes: Separations, structural analysis and applications

“…As another way of separation, filtration (micro-, nano-, and ultrafiltration) could disorder physical states of asphaltenes. There are mainly two kinds of membranes, inorganic and organic membranes, including zirconia membrane [70] , Ultracel YM and nanopore membrane [71] , asymmetric ceramic monolith membranes [72] , and polyethersulfone and polyimide porous membranes [73,74] , which are widely applied in separation process. Asphaltene was separated experimentally using mica membranes (pore radius 8-220 nm) and Wicke-Kallenback-type diffusion cell in early 1983 [1] .…”