Chemical Bulletin of Kazakh National University

Thermal treatment of model water-in-oil emulsions by coal fly ash particles

Saidulla N. Faizullayev — 2025-03-31

One of the primary challenges in the oil industry is the formation of stable crude oil emulsions, which cause equipment and pipeline corrosion due to the inorganic salts dissolved in the aqueous phase. This study investigated the effect of coal fly ash on model crude oil emulsions. The model emulsions were prepared using crude oil samples from the Kyzylorda and Atyrau regions. Thermal demulsification at 60°C resulted in a low dewatering rate, with only 16% of water separated from a 50% water-in-oil emulsion. Higher efficiency in oil emulsion separation was observed using the microwave treatment method. The highest dewatering degree was achieved for the Atyrau crude oil emulsion, reaching 75% after 155 seconds for a 50% emulsion with a 1% ash concentration at a microwave power of 700 W, while the dewatering for the Kyzylorda oilfield emulsion was 50% under the same conditions. This difference in demulsification efficiency is attributed to the composition of the crude oil samples. It has been demonstrated that the microwave treatment method combined with the use of coal fly ash enables the separation of water-in-oil emulsions within a short period.

Mіnі-rеvіеw: Advаnсеs іn thе sуnthеsіs аnd bіоlоgісаl асtіvіtу оf bеnzоfurохаn аnd furохаn dеrіvаtіvеs

Mukhtar N. Zhаnаkоv — 2025-03-31

Benzofuroxan and furoxan derivatives are heterocyclic compounds well known for their ability to act as nitric oxide (NO) donors. Due to their NO-releasing properties, these compounds have attracted considerable attention for their antimicrobial, antiviral, and antitumor activities. Their potential use in treating cardiovascular, gastrointestinal, and neurodegenerative disorders further underscores their pharmacological relevance. Given the increasing research interest in these compounds, there is a need to consolidate recent findings related to their chemical properties and biological potential. This mini-review aims to provide an up-to-date overview of the synthetic strategies and bioactivities of benzofuroxan and furoxan derivatives. Rather than focusing on ring synthesis, this review highlights the reactivity of side-chain functional groups and the design of hybrid molecules. Representative examples of drug-like compounds are discussed, along with their biological profiles. The review also explores emerging directions in the development of novel NO donors based on these frameworks with improved pharmaceutical efficacy and controlled NO release.

Synthesis, electronic and emission spectroscopy of diphenylamine-azulene co-oligomers

Nurlan Merkhatuly — 2025-03-31

New strategies for creating functional materials are of great interest for the further development of optoelectronic devices such as organic field-effect transistors (OFETs), organic light emitting diodes (OLEDs), dye-sensitized organic solar cells (DSSCs) and others. In this area, research has focused on the application of various building blocks that can fine-tune the electronic structure of materials to optimize the fabrication performance and morphology. To date, the most effective molecules as building block are aromatic hydrocarbons, for example azulenes.
In this study, new conjugated diphenylamine-azulene co-oligomers with linear and branched structures were synthesized with high yields via the Suzuki–Miyaura cross-coupling reaction. The obtained co-oligomers exhibit a pronounced ability to absorb and emit visible light in the 400–700 nm range. It was demonstrated that these unique photophysical properties, particularly the intense emissions in the green and orange photoluminescence range, result from the electron-donating properties of diphenylamine groups and the expansion of π-conjugation, which significantly alters the electronic structure of azulene, including the levels and energy gaps of the frontier HOMO-LUMO orbitals. These findings provide a rational approach to designing a series of new conjugated co-oligomers based on diphenylamine-azulenes for optoelectronic and photonic devices.