Sustainable valorization of asphaltenes via flash joule heating

Asphaltene-derived nanocomposites for the removal of emerging pollutants and its antimicrobial effects: batch and continuous column studies

Emerging contaminants are diverse ecotoxic materials requiring unique treatment for removal. Asphaltenes are environmentally hazardous carbon-rich solid waste product of the petroleum industry. In the current work, asphaltene-derived activated carbon (AC) was loaded with silver (Ag/AC) and used to remove amoxicillin (AMX) and tetracycline (TC) from aqueous phase. The prepared Ag/AC was characterised using FESEM, FTIR, XRD and surface area analysis. The FESEM micrographs confirmed the spherical silver nanoparticle-laden porous AC, and the BET surface area was found to be 213 m2/g. Batch adsorption studies were performed, and the equilibrium data were fit into adsorption isotherm and kinetic models. The Ag/AC exhibited superior monolayer adsorption capacity of 1012 mg/g and 770 mg/g for AMX and TC, respectively. The continuous column studies were also performed to evaluate the breakthrough parameters. Furthermore, the antimicrobial activity of the adsorbent was evaluated using zone of inhibition studies. Ag/AC was found to have an 8-mm-diameter zone of microbial inhibition. The obtained results showed that Ag/AC was a promising material for the removal of antibiotics and inhibition of resistance-developed mutated microbes in effluent water.

Effectiveness of inhibitors to prevent asphaltene aggregation: Insights from atomistic and molecular simulations

The technological landscape for industrial processes handling asphaltene is evolving at a rapid pace due to the increase in the extraction of heavy crude oil. The main underlying challenges in this regard are the flow assurance, the recovery of the spent solvent, and the sophisticated extractor setup required to develop the process to an industrial scale. The number of studies focused on the handling of the asphaltene at the atomic and molecular scales is growing enormously in order to identify new sustainable solvents for the effective extraction of asphaltene from heavy crude oil or oil-bearing sands. This Perspective focuses on the importance of density functional theory and molecular dynamics simulations to explore the broader range of asphaltene inhibitors, e.g., nanoparticles, ionic liquids, and deep eutectic solvents, to prevent asphaltene precipitation. We provide a concise overview of the major accomplishments, analyze the aspects that require attention, and highlight the path-breaking studies having a significant impact on the process of chemical enhanced oil recovery from heavy crude oil reservoirs primarily based on atomistic and molecular simulations.

Polymer Additives with Gas Barrier and Anti-Aging Properties Made from Asphaltenes via Supercritical Ethanol

Asphaltene is often regarded as an undesirable by-product of petroleum processing, possesses vast reserves with little market value. The typical routes of consuming asphaltene, namely burning and landfilling, pose significant environmental challenges. In this study, low-value asphaltene is converted into high-value ethylated carbon clusters (ECC) using a supercritical ethanol technique. The resulting ECC powder demonstrates promising properties for high density polyethylene (HDPE) composite applications. The effects of incorporating ECC on the mechanical, gas barrier, and anti-aging properties of the composite are investigated. Results show that a 1 wt.% ECC led to a 4.2% and 43.5% increase in tensile strength and elongation at break, a reduction of 45.8% and 30.7% in oxygen and carbon dioxide permeability. Furthermore, ECC exhibits effective UV spectrum absorption and conversion in the wavelength range of 400-600 nm, providing protection against UV spectrum damage to HDPE. The incorporation of ECC not only enhances the properties of polymer composites but also sequesters carbon within the polymer matrix, enabling the valorization of asphaltene while mitigating environmental impact.

Replacement of Concrete Aggregates with Coal-Derived Flash Graphene

Each year, the growth of cities across developing economies in Asia, Africa, and Latin America drives demand for concrete to house and serve their burgeoning populations. Since 1950, the number of people living in urban areas has quadrupled to 4.2 billion, with another predicted 2.5 billion expected to join them in the next three decades. The largest component of concrete by volume is aggregates, such as sand and rocks, with sand as the most mined material in the world. However, the extraction rate of sand currently exceeds its natural replenishment rate, meaning that a global concrete-suitable sand shortage is extremely likely. As such, replacements for fine aggregates, such as sand, are in demand. Here, flash Joule heating (FJH) is used to convert coal-derived metallurgical coke (MC) into flash graphene aggregate (FGA), a blend of MC-derived flash graphene (MCFG), which mimics a natural aggregate (NA) in size. While graphene and graphene oxide have previously been used as reinforcing additives to concrete, in this contribution, FGA is used as a total aggregate replacement for NA, resulting in 25% lighter concrete with increases in toughness, peak strain, and specific compressive strength of 32, 33, and 21%, respectively, with a small reduction in specific Young's modulus of 11%. FJH can potentially enable the replacement of fine NA with FGA, resulting in lighter, stronger concrete.