Asphaltene Cross-flow Membrane Ultrafiltration on a Preparative Scale and Feedstock Reconstitution Method

S. Brunet,L. Barré,I. Merdrignac,D. Guillaume,J. Marques,D. Espinat

doi:10.2516/ogst/2009053

Abstract

In order to understand asphaltene reactivity under hydrotreatment conditions, a new strategy is proposed. A cross-flow membrane ultrafiltration method is applied in order to control asphaltene aggregate size polydispersity. At the same time, a feedstock reconstitution method that allows asphaltene dispersion in maltenes is established. Catalytic tests are carried out, showing that the developed feedstock reconstitution method allows one to preserve asphaltenes' natural reactivity under hydrotreatment conditions. In further studies, the developed methodology will allow the study of the effect of asphaltene aggregate size on hydrotreatment activities by the reconstitution of feedstocks containing controlled aggregate size.

Highlights

Worldwide trends indicate a decline in the availability of conventional crude oil, which is balanced by the increasing exploitation of heavy crude
It was seen that the LMwAsC7 represent 22 wt% and HMwAsC7 represent 78 wt% of the initial asphaltene aggregate sample, which is an important fact relevant to further interpretations
Size-Exclusion Chromatography (SEC) and Small-Angle X-ray Scattering (SAXS) results confirmed that two distinct asphaltene fractions are obtained: SEC: Mw LMwAsC7 ~ 3600 g.mol-1 eq PS; Mw HMwAsC7 ~ 9000 g.mol-1 eq PS;

Summary

Introduction

Worldwide trends indicate a decline in the availability of conventional crude oil, which is balanced by the increasing exploitation of heavy crude. This trend makes it crucial to have modern refineries adapted to the upgrading of distillation petroleum residues. Petroleum residues contain high quantities of sulfur that can be eliminated by hydrotreatment (HDT) using fixed bed units (Leprince, 1998). From this process an ultra-low sulfur fuel can be obtained, as well as a product that can be further upgraded in a Residue Catalytic Cracker (RCC). The first section is dedicated to the elimination of asphaltenes and metals from the feedstock (HDM section), sulfur is deeply removed in the HDS section

Methods

Results

Conclusion