Hybrid of quantum dots for interfacial tension reduction and reservoir alteration wettability for enhanced oil recovery (EOR)

Fabrication and Optimization of Pickering Emulsion Stabilized by Lignin Nanoparticles for Curcumin Encapsulation

To develop reversible pH-responsive emulsifiers of natural origin, alkali lignin (AL) was used to develop oil-in-water Pickering emulsions. AL was first modified to synthesize quaternized alkali lignin (QAL), which displayed pH-responsive properties and demonstrated solubility in both acidic and alkaline solutions. In contrast, QAL exhibited insolubility and formed particles in neutral solutions, thereby making it a suitable candidate for utilization as an emulsifier in doubly pH-responsive Pickering emulsions. At pH 5-9, the emulsions were stable. Above or below this pH range, the system demulsifies, resulting in a reversible Pickering emulsifier with two pH-controlled transitions. On the basis of this pH-dependent behavior, lignin-based Pickering emulsions (LPE) could be subjected to several cycles of emulsification-demulsification by alternating the pH of the aqueous phase between basic and acidic, while the droplet size and storage stability were maintained. Curcumin was used as a drug model to study the loading/release behavior of LPE, finding that 50.08% of curcumin could be encapsulated in LPE. The in vitro release of curcumin was pH-dependent. In addition, LPE exhibited an outstanding protective effect against the ultraviolet-induced degradation of curcumin.

Recent advances in the applications of graphene materials for the oil and gas industry

Graphene is a material formed with carbon atoms connected by sp2 hybridization. It is extremely strong and very ductile, and is superhydrophobic and superlipophilic. It has important application prospects in materials science, micro and nano processing, energy, aerospace and biomedicine. Graphene also has some applications in the petroleum industry. As nanoscale materials, graphene-based materials can plug nano-pores and prevent water intrusion into clay minerals during the drilling process, they are suitable for sliding between layers and can be used as lubricants due to the two-dimensional structure. The adsorption properties of graphene-based materials allow them to improve the treatment rate when treating oily wastewater. This paper compiles recent advances in the application of graphene and its derivatives in oilfield extraction, including improving drilling fluid performance, enhanced oil recovery and oily wastewater treatment. We compare the performance advantages of graphene-based materials over other additives, and summarize the mechanism of action of graphene-based materials. The shortcomings of current research are identified and future research and improvement directions are envisaged.

Quantum dot synthesis from waste biomass and its applications in energy and bioremediation

Quantum dots (QDs) are getting special attention due to their commendable optical properties and applications. Conventional metal-based QDs have toxicity and non-biodegradability issues, thus it becomes necessary to search for renewable precursor molecules for QDs synthesis. In recent years, biomass-based carbon rich QDs (CQDs) have been introduced which are mainly synthesised via carbonization (pyrolysis and hydrothermal treatment). These CQDs offered higher photostability, biocompatibility, low-toxicity, and easy tunability for physicochemical properties. Exceptional optical properties become a point of attraction for its multifaceted applications in various sectors like fabrication of electrodes and solar cells, conversion of solar energy to electricity, detection of pollutants, designing biosensors, etc. In recent years, a lot of work has been done in this field. This article will summarize these advancements along in a special context to biomass-based QDs and their applications in energy and the environment.