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

Abstract

Metals in petroleum fractions have a deleterious effect on the refining equipment and catalyst. They corrode the equipment, plug the catalyst pores, and create irregularities in the system. With reference to today's petroleum industry, the fast depletion of light crude has created the need to process heavier crudes with much higher metal content. Hence, the need to remove traces of harmful metals and restrict their accumulation in feed stocks has become a pressing issue. In this context, we review developments over the past decade in regard to the methods of metal removal with a focus on unconventional methods, such as the use of molecularly imprinted polymers, supercritical fluids, and irradiation. Other methods of demetallization discussed include the usage of nanocatalysts, micro-organisms, and certain solvents. The removal of vanadium and nickel were reviewed most, because of the abundance of these elements in the crude.

Temperature and Pressure Effects on the Catalytic Performance of Metalloporphyrins during Hydrogenation of Naphthalene

“…Heavy oil is abundant with nickel and vanadium . These inherent metals generally deposit as metal sulfides in heavy oil upgrading process and accelerate coke formation in non‐catalytic thermal process .…”

The development of industrial (thermal) processes in the context of sustainability: The case for microwave heating

“…It has been demonstrated that the concentration of various metals existing in heavy oils varies from a few parts per million to higher than 1000 ppm, as shown in Table . Some of the most distinct elements that have been identified in oil include cobalt (Co), nickel (Ni), copper (Cu), vanadium (V), silver (Ag), sodium (Na), potassium (K), lithium (Li),calcium (Ca), and strontium (Sr) …”

Fundamental Studies on Etioporphyrin Removal from Model Oil Using Toluene Assisted Ionic Liquids

“…al. stated that Ni and V are the most abundant heavy metals to be found in natural crude oil [6]. Generally, both metals are usually found as a porphyrinic structures.…”

“…A common porphyrinic compound is known as metal porphyrin. A metal porphyrin formed as a metal atom displaces two central hydrogen ions which then forms a metal complex [6]. This chelated metal is highly stable thus making demetalization process extremely problematic.…”