Радикальная сополимеризация стирола и α-ангеликалактона: синтез и свойства полученных сополимеров

Biodegradation ability of synthetic polymer materials is an urgent problem of modern ecology situation. A known new biodegradable polymer is polyangelicalactone (PAL). In this paper, styrene-α- angelicalactone copolymers were obtained by radical polymerization. The resulting copolymers have physical and mechanical properties similar to those of polystyrene and its graft-copolymers with PAL. Both they were mechanically destroyed when incubated in gray forest soil over 28 weeks. The obtained results show that the modification of polystyrene with the impurities of α-angelicalactone does not worsen the mechanical properties of the copolymers but instead gives them biodegradation abilitiesВ настоящей работе получены сополимеры стирола и α-ангеликалактона методом радикальной полимеризации. Полученные сополимеры имеют физико-механические свойства, аналогичные свойствам полистирола и его привитых сополимеров с полиангеликалактоном. Оба полимера механически разрушаются при инкубации в серой лесной почве в течение 28 недель. Полученные результаты показывают, что модификация полистирола примесями α-ангеликалактона не ухудшает механические свойства сополимеров и придает им способность к биоразложени

Towards sustainable production of formic acid

peer-reviewedFormic acid is a widely used commodity chemical. It can be applied as a safe, easily handled and transported source of hydrogen or CO for different reactions including those producing fuels. The review includes historical aspects of formic acid production. It shortly analyzes the production based on traditional sources such as toxic CO, methanol and methane. However, the main emphasis is done to the sustainable production of formic acid from biomass and biomass-derived products via hydrolysis, wet and catalytic oxidation processes. New strategies of low temperature synthesis from biomass may lead to utilization of formic acid for production of fuel additives such as methanol, upgraded bio-oil, γ-valerolactone and its derivatives, as well as synthesis gas used for Fischer-Tropsch synthesis of hydrocarbons. Some technological aspects are considered

Electroanalysis may be used in the Vanillin Biotechnological Production

This study shows that electroanalysis may be used in vanillin biotechnological production. As a matter of fact, vanillin and some molecules implicated in the process like eugenol, ferulic acid, and vanillic acid may be oxidized on electrodes made of different materials (gold, platinum, glassy carbon). By a judicious choice of the electrochemical method and the experimental conditions the current intensity is directly proportional to the molecule concentrations in a range suitable for the biotechnological process. So, it is possible to imagine some analytical strategies to control some steps in the vanillin biotechnological production: by sampling in the batch reactor during the process, it is possible to determine out of line the concentration of vanillin, eugenol, ferulic acid, and vanillic acid with a gold rotating disk electrode, and low concentration of vanillin with addition of hydrazine at an amalgamated electrode. Two other possibilities consist in the introduction of electrodes directly in the batch during the process; the first one with a gold rotating disk electrode using linear sweep voltammetry and the second one requires three gold rotating disk electrodes held at different potentials for chronoamperometry. The last proposal is the use of ultramicroelectrodes in the case when stirring is not possible

Determination of hydroxyl groups in biorefinery resources via quantitative 31P NMR spectroscopy

The analysis of chemical structural characteristics of biorefinery product streams (such as lignin and tannin) has advanced substantially over the past decade, with traditional wet-chemical techniques being replaced or supplemented by NMR methodologies. Quantitative 31P NMR spectroscopy is a promising technique for the analysis of hydroxyl groups because of its unique characterization capability and broad potential applicability across the biorefinery research community. This protocol describes procedures for (i) the preparation/solubilization of lignin and tannin, (ii) the phosphitylation of their hydroxyl groups, (iii) NMR acquisition details, and (iv) the ensuing data analyses and means to precisely calculate the content of the different types of hydroxyl groups. Compared with traditional wet-chemical techniques, the technique of quantitative 31P NMR spectroscopy offers unique advantages in measuring hydroxyl groups in a single spectrum with high signal resolution. The method provides complete quantitative information about the hydroxyl groups with small amounts of sample (~30 mg) within a relatively short experimental time (~30-120 min)

Bright Side of Lignin Depolymerization:Toward New Platform Chemicals

Lignin, a major component of lignocellulose, is the largest source of aromatic building blocks on the planet and harbors great potential to serve as starting material for the production of biobased products. Despite the initial challenges associated with the robust and irregular structure of lignin, the valorization of this intriguing aromatic biopolymer has come a long way: recently, many creative strategies emerged that deliver defined products via catalytic or biocatalytic depolymerization in good yields. The purpose of this review is to provide insight into these novel approaches and the potential application of such emerging new structures for the synthesis of biobased polymers or pharmacologically active molecules. Existing strategies for functionalization or defunctionalization of lignin-based compounds are also summarized. Following the whole value chain from raw lignocellulose through depolymerization to application whenever possible, specific lignin-based compounds emerge that could be in the future considered as potential lignin-derived platform chemicals

A New Vanadium Catalyst for Chlorine Production by Hydrogen Chloride Oxidation

Показано, что промышленный ванадиевый катализатор окисления диоксида серы ИК-1-6 активен в процессе окисления хлористого водорода в молекулярный хлор (производительность до 180 грамм хлора на килограмм катализатора в час при 400 оС). Показано, что катализатор стабилен в течение 6 часов и предложены пути создания стабильно работающей каталитической установки для производства хлора.Industrial vanadia catalyst for SO2 oxidation, IK-1-6, was shown to be efficient in a process of hydrogen chloride oxidation into molecular chlorine. The productivity of the catalyst attains values of 180 grams of chlorine per kilogram of catalyst per hour at 400 oC. The catalyst was shown to be stable for 6 hours. A way to create a stable-operating catalytic system for chlorine production is suggested

A Novel Vanadium Catalyst for Oxidation of Hydrogen Chloride with Dioxygen

A novel catalytic system for oxidation of hydrogen chloride, V2O5-LiCl-KCl, has been studied. This catalyst shows activity in a range of relatively low temperatures, 250 - 350 °C. Chlorine yield attains 200 - 780 g per kg of catalyst per hour at 350 °C, which greatly exceeds the characteristics of known vanadium, copper and chromia catalysts

Study of Plant Growth Promoting Activity and Chemical Composition of Pine Bark after Various Storage Periods

Composition and content of terpene compounds in pine bark (Pinus sylvestris) after various storage periods were studied by GLC-MS. Resin acids were found to be the main diterpenoic compounds in the bark. Content of dehydroabietic acid in initial bark is 0.6 g/kg and it decreases three-fold after one year of storage. High activity of pine bark after various storage periods towards risogenesis of wheat (Triticum aestivum) was discovered. Strong correlation (r = 0.89) between growth promoting activity of pine bark and content of dehydroabietic acid in it was found