Kinetics and mechanisms of the catalytic thermal cracking of asphaltenes adsorbed on supported nanoparticles

Abstract

The production of heavy and extra-heavy oil is challenging because of the rheological properties that crude oil presents due to its high asphaltene content. The upgrading and recovery processes of these unconventional oils are typically water and energy intensive, which makes such processes costly and environmentally unfriendly. Nanoparticle catalysts could be used to enhance the upgrading and recovery of heavy oil under both in situ and ex situ conditions. In this study, the effect of the Ni-Pd nanocatalysts supported on fumed silica nanoparticles on post-adsorption catalytic thermal cracking of n-C 7 asphaltenes was investigated using a thermogravimetric analyzer coupled with FTIR. The performance of catalytic thermal cracking of n-C 7 asphaltenes in the presence of NiO and PdO supported on fumed silica nanoparticles was better than on the fumed silica support alone. For a fixed amount of adsorbed n-C 7 asphaltenes (0.2 mg/m 2 ), bimetallic nanoparticles showed better catalytic behavior than monometallic nanoparticles, confirming their synergistic effects. The corrected OzawaFlynn-Wall equation (OFW) was used to estimate the effective activation energies of the catalytic process. The mechanism function, kinetic parameters, and transition state thermodynamic functions for the thermal cracking process of n-C 7 asphaltenes in the presence and absence of nanoparticles are investigated.

Metal Oxide Nanoparticles Supported on Macro-Mesoporous Aluminosilicates for Catalytic Steam Gasification of Heavy Oil Fractions for On-Site Upgrading

“…However, supports functionalization process enhanced the CH4 production by the presence of different active sites, confirming the catalytic activity of the functionalized catalysts. Metal oxide nanoparticles guarantee a high CH4 production at lower temperatures [100], also promote the R-A conversion into light products with the following trend KMoCo < KMoNi < CMoCo < CMoNi < K< R-A< C. Partial oxidation, water-gas and steam reforming are associated with CO production, however, the evolution profile does not show a representative CO production in the evaluated catalyst, suggesting the promotion of the methanation reaction. Evolution profiles of light hydrocarbons (LCH), CO2, CO and CH4 for R-A decomposition in presence of KMoNi under inert and steam atmospheres are shown in Figure 9.…”

“…The R-A decomposition in the presence and absence of KMoNi sample under an inert atmosphere is shown in Figure 4. The KMoNi catalyst under inert atmosphere enhances the R-A cracking at lower temperatures by the presence of active sites which catalyzes the chains rupture [100]. Virgin R-A decomposition begins at 545 K and 485 K for pyrolysis and steam gasification process respectively, which suggests that the steam atmosphere improve the short and long chain rupture by the saturation and partial oxidation of the molecules [101].…”

“…The selectivity behavior during the catalytic process was studied by tracing the produced gasses using FTIR analysis [72,100,103]. Steam gasification of R-A fractions as carbonaceous source contains reactions such as water-gas shift reaction, partial oxidation, steam reforming reactions, boundary equilibrium reaction and methanation [72].…”

An Overview of the Present Stability and Performance of EOR-Foam

“…They serve as promoters to provide optimal conditions with respect to temperature, pressure and salinity (Fathi & Ramirez 1984). Figure 8 typically describes an example of nanoparticles (silica nanoparticle) which has the ability to form a definite bond with the amphiphilic head of a foaming agent, thereby improving its thermal properties (Hesemann et al 2014) as well as increase the oil recovery (Montoya et al 2016).…”

Enhanced in situ combustion of heavy crude oil by nickel oxide nanoparticles

“…() Montoya studied the effect of Ni‐Pd nanocatalyst on thermal cracking of n‐C 7 asphaltene using TG‐FTIR and observed the synergistic effect of Ni‐Pd. Upon using Ni‐Pd nanocatalyst, the AE was reduced by 27%, while the value for monometallic Ni was only 20.3% . Nassar et al performed investigation on catalytic asphaltene adsorption and thermal cracking by application of NiO , Fe 2 O 3 , and Co 3 O 4 .…”