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The production of propylene by dehydration of 2-propanol at solid-vapor interfaces, as an example of the acidcatalyzed surface reaction, was explored by using sulfonated polyacrylonitrile-derived activated carbon fibers (PAN-ACFs). To prepare these catalysts, the PAN-ACFs obtained by onestep carbonation-activation were modified with a surface coverage of high acidity. The surface of PAN-ACFs was sulfurated with sulfur vapors at high temperatures followed by oxidation, to yield the corresponding sulfonates. The chemical analysis showed that the carbon surface layer contains from 1.28 to 6.10 mmol$\mathrm{g}^{-1}$ of sulfur, including the contribution of sulfonic $(\mathrm{S}\mathrm{O}{}_{3}\mathrm{H})$ groups. In addition to sulfonic groups, the obtained catalysts contain carboxyl, lactone, and phenolic groups, which are formed as a result of oxidation treatment. In order to understand the changes in surface chemistry and the results of sulfuration and oxidation, the sulfonated PAN-ACFs were characterized by a variety of techniques including TPD MS, TGA, SEM, and FTIR ATR. During a typical temperature mode screening at catalyst testing, it was found that the sulfonated PAN-ACFs prepared by treatment with sulfur vapor at low temperature, at $400\circ \mathrm{c}$ and $500\circ \mathrm{c}$, are very efficient at dehydrating 2-propanol. A weighed mass of 100 mg of each of these catalysts was operated at 165-175°C in 12 hours, and the catalysts were characterized by high conversion of 2-propanol and high selectivity to propylene, with a propylene yield of about 100%. Furthermore, the solid acid catalysts have high stability and strong acidity and can be reused with no significant loss in the activity after the third cycle in the subsequent 20 cycles. The preparation of solid acid catalysts from PAN-ACFs affords a novel strategy for producing propylene through alternative green and sustainable technologies.

Oxidation of activated carbon (AC) with nitric acid was carried out, and the resulting AC/HNO 3 showed high capacity when used as supercapacitor electrode material operated in the KOH electrolyte. Oxidation caused different structural changes in the AC, reducing the specific surface area and the total pore volume. After oxidation, the content of all types of oxygen-containing groups and, especially, carboxyl groups showed a significant increase. Despite the significant reduction of the specific surface area, the specific capacitance of the oxidized AC in symmetric supercapacitor electrodes is 1.4 times larger than that for the pristine AC.

Here we report on the preparation of effective aminated sorbents based on activated carbon (AC), which was produced from natural raw material (Apricot pits) for the removal of heavy metal ions from wastewaters. For effective functionalization, bromination and following amination were carried out. At the amination stage, the grafted bromine groups were substituted by amino groups. Amination by ethylenediamine and monoethanolamine alcohol solutions can replace 0.52 mmol of bromine groups by 0.51–0.57 mmol of amino groups per gram of sorbent. We showed that the aminated ACs could remove 90% of Cu(II) ions from aqueous solutions containing from 4×10−5 to 1×10−3 mol/L of Cu2+. The regeneration of used sorbents and the recovery of copper were also studied to evaluate the reusability of the sorbents.

estimation of toxicity of two new classes of heterocyclic condensed cationic surfactants was performed. The general synthetic approaches for obtaining the target heterocyclic systems of 1,2,4-triazole and thieno[2,3-d]pyrimidine classes were discussed and the main routes to increasing of the chemical libraries through the efficient introduction of long-chain substituents were pointed out. The estimation of toxicity was done through: (a) the prediction of the LD 50 values of acute rat oral toxicity with using GUSAR free online service; (b) the prediction of the LC 50 values of fathead minnow with 96 hours exposure, which were predicted with using T.E.S.T. software. Computed LD 50 and LC 50 values testify that proposed heterocyclic surfactants have the toxicity rates close to the widely used surfactants like cetylpyridinium chloride, cetyltrimethylammonium bromide, and benzalkonium chloride. Consequently, target cationic surfactants of 1,2,4-triazole and thieno[2,3-d]pyrimidine series can be considered as non-toxic detergents and will be synthesized for the next biological testing as disinfectants.

Fused pyrimidines are important structural motifs in material science, medicinal chemistry, and are useful building blocks in organic synthesis. Herein we report a new approaches in preparation of condensed thieno[2,3-d]pyrimidine-containing non-toxic compounds via environmentally friendly technologies. The microbiological activity of received compounds is also discussed.

The fluoroquinolones are one of the most widely used classes of antibiotics. Enrofloxacin belongs to the class of fluoroquinolone antibiotics that have been intensively used for the treatment of bacterial infections in veterinary medicine. When antibiotic residues enter the soil, the main processes determining their persistence are sorption to organic particles and degradation. The article presents the results of studies on the sorption of enrofloxacin by different crops, provided that it’s various concentrations in the soil (1000mg·kg−1, 100mg·kg−1, 10mg·kg−1). Experimental studies have shown that the activity of absorbed antibiotics depends on its concentration in the soil and species of an agricultural plant. It was found that the most active antibiotic absorbs Lactuca sativa var. Crispa and Calendula officinalis. The lowest content of enrofloxacin among the five plants was in Mentha piperita. Adding to the soil of enrofloxacin at a concentration of 1000 mg·kg−1 leads to the formation of a high level of soil toxicity. In model ecosystems with Thymus serpillum and Mentha piperita, soil toxicity was more than 70%. The toxicity of enrofloxacin in the soil within In vivo experiments was on average 10% lower than in laboratory tests. The highest phytotoxic effect was observed in the soil of model ecosystems, where the concentration of enrofloxacin was 1000 mg·kg−1. It should be noted that in the soil where Lactuca sativa was grown, the phytotoxic effect was 56.17 % (In vitro) and 49.22% (In vivo). This is due to the active absorption of antibiotic by plants, which minimized the toxicity of the soil. The different terrestrial toxicological effects of enrofloxacin were studied using a series of bioassays and including sorption of fluoroquinolone antibiotic by five crop plants. Enrofloxacin is highly resistant, its biodegradation process is longer than other antibiotics, it is actively absorbed by the plants, and therefore it is necessary to control it content in phytoproduction.

The presented study is dedicated to the green synthesis of stable gold and silver nanoparticles using natural polyphenols isolated from blackcurrant (Ribes nigrum L.) extract. A polyphenol fraction was prepared from the raw extract of blackcurrant fruits using solid-state extraction (C 18 reversed-phase). HPLC-DAD chromatography analyses have shown that the major components of used extract were anthocyanins (delphinidin-3-glucoside, delphinidin-3-rutinoside, cyanidin-3-glucoside, and cyanidin-3-rutinoside). Green protocol for the synthesis of gold and silver nanoparticles was developed through the optimization of reaction conditions (reactants ratio, pH of solutions, reaction time and temperature). The alkali conditions were observed to be necessary for the synthesis of highly mono-disperse spherical gold nanoparticles (diameter of 10 nm).