Halloysite clay nanotubes loaded with corrosion inhibitors benzotriazole (BTA), 2-mercaptobenzimidazole (MBI), and 2-mercaptobenzothiazole (MBT) were used as additives in self-healing composite paint coating of copper. These inhibitors form protective films on the metal surface and mitigate corrosion. Mechanisms involved in the film formation have been studied with optical and electron microscopy, UV-vis spectrometry, and adhesivity tests. Efficiency of the halloysite lumen loading ascended in the order of BTA < MBT < MBI; consequently, MBI and MBT halloysite formulations have shown the best protection. Inhibitors were kept in the tubes buried in polymeric paint layer for a long time and release was enhanced in the coating defects exposed to humid media with 20-50 h, sufficient for formation of protective layer. Anticorrosive performance of the halloysite-based composite acrylic and polyurethane coatings have been demonstrated for 110-copper alloy strips exposed to 0.5 M aqueous NaCl for 6 months.

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In this paper, adsorptive desulfurization of the gasoline produced from low-pressure hydrocracking of the atmospheric residue was studied. Gasoline obtained from such a process has a high sulfur content and is not suitable for use as a motor fuel without further desulfurization. A nickel-modified natural bentonite catalyst was developed and used in the process. The reaction temperature and flow rate were adjusted to maximize the sulfur removal efficiency while fixing the pressure at 2.5 MPa. Optimal sulfur removal was obtained at 270 °C and 1.0 h–1 feed rate, reducing the gasoline sulfur level from 450 to 32 ppm without affecting the hydrocarbon content and, hence, preserving the octane number. Sulfur adsorbs on nickel nanoparticles by forming nickel sulfide, and the catalyst can be regenerated by subsequent oxidation with air, followed by reduction with hydrogen gas.

The presented article shows the studies of hydrocracking process of fuel oil with the purpose of obtaining light oil products (benzene and diesel fractions) from heavy oil residues (fuel oil), thus, deepening the refining of oil. The hydrocracking of fuel oil was conducted in the presence of halloysite modified with transition metals (Mo, Ni). Toward this end, halloysite was modified by two different methods—absorption and ion-exchange methods. It was shown that, at optimal conditions (430 °C, 4 MPa), 46.6% (wt.), 53.0% (wt.), 63.0% (wt.) and 83.0% (wt.) light oil products are obtained by the hydrocracking process of fuel oil carried out without catalyst, in the presence of unmodified halloysite, halloysite modified by absorption method and halloysite modified by ion-exchange method, respectively. The obtained benzene and diesel fractions after hydrorefining process can be added to fuels as components.

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