Aluminum Oxide Nanoparticles for Highly Efficient Asphaltene Separation from Crude Oil Using Ceramic Membrane Technology

¹ Department of Chemical Engineering, Shahrood University of Technology, Shahrood - Iran
² Separation Processes Research Group (SPRG), Department of Engineering, University of Kashan, Kashan - Iran
³ Energy Research Institute, University of Kashan, Ghotb-e-Ravandi Ave., Kashan - Iran
⁴ Upgrading and Optimization Technologies Group, Petroleum Refining Division, Research Institute of Petroleum Industry, 14665-1998 Tehran - Iran

^* Corresponding author e-mail: mashallah.rezakazemi@gmail.com

Received: 3 February 2017
Accepted: 12 September 2017

Abstract

The effects of aluminum oxide nanoparticles on the removal of asphaltenes from an Iranian crude oil (Soroush) using a ceramic membrane with pore size of 0.2 µm were investigated. In order to achieve superior asphaltene separation by ultrafiltration, it is essential to make some changes for destabilizing asphaltene in crude oil. The asphaltene destabilization was done using crude oil contact with an acid containing dissolved metal ions. Metal oxide nanoparticles adsorbed asphaltene molecules and increased their molecular size. The nanoparticle of aluminum oxide was applied to alter precipitation and peptization properties of asphaltenes. Dynamic Light Scattering (DLS) was used to measurement of the asphaltene molecular size dissolved in toluene. Raman spectroscopy and the Tuinstra equation were used to determine the aromatic sheet diameter (L_a) via the integrated intensities of the G and D1 modes. This revealed that the asphaltene particles react with nano aluminum oxide and the average molecular size of asphaltene was raised from 512.754 to 2949.557 nm and L_a from 5.482 to 13.787. The obtained results showed that using nano aluminum oxides, asphaltene separation increased from 60–85 wt% to 90–97 wt% based on the asphaltene content of crude oil.