A novel method of synthesis of mesoporous, polymer-derived CMK-3 carbon replica was proposed. Instead of a multi-stage, time-consuming and toxic solvent involving procedure, the direct, acid-catalyzed precipitation polycondensation of furfuryl alcohol to poly(furfuryl alcohol) (PFA), as the carbon precursor, in the pore system of SBA-15 silica was used. The optimal PFA/SBA-15 mass ratio resulting in the complete pore filling was found. The final carbon material was obtained by carbonization of the formed composite and subsequent removal of silica by treatment with HF. Low-temperature sorption of nitrogen, powder X-ray diffraction and transmission electron microscopy confirmed the formation of well-ordered, hexagonal carbon mesostructure. The produced CMK-3 exhibited the presence of oxygencontaining surface groups, recognized as mainly carbonyl and carboxyl species by X-ray photoelectron spectroscopy and temperature-programmed desorption. The presence of these * Corresponding author. Tel: +48 12 6632006; Fax: +48 12 6340515. E-mail address: kustrows@chemia.uj.edu.pl (P. Kuśtrowski) 2 groups caused the mesoporous carbon to be catalytically active in the oxidative dehydrogenation of ethylbenzene to styrene.

Thermogravimetry, diffuse reflectance infrared Fourier transform spectroscopy, and X-ray photoelectron spectroscopy (XPS) were used for the studying of thermally induced structural changes of polyacrylonitrile (PAN) deposited on the surface of SBA-15 type mesoporous silica. Polymer was introduced onto the support by the precipitation polymerization of acrylonitrile in aqueous suspension of SBA-15. Low temperature transformation (to 723 K) of the deposited PAN was analyzed. It was found that at about 523 K, exothermic cyclization of polymer chains to the so-called ladder form of PAN occurred. However, the total cyclization of PAN required higher carbonization temperatures, at which gradual dehydrogenation followed by graphitization was initiated. XPS revealed that the cyclic form of PAN and a relatively large amount of carbonyl species, formed during the carbonization of the PAN/SBA-15 composite at 623 K, were responsible for the high sorption capacity in the methylethyl ketone (MEK) vapor elimination. The efficiency in the MEK adsorption was also influenced by the content of PAN-derived carbon deposited on the SBA-15 surface.Keywords Thermal transformation of polyacrylonitrile Á SBA-15 support Á Thermogravimetry Á X-ray photoelectron spectroscopy Á Diffuse reflectance Fourier transform spectroscopy Á Adsorption of volatile organic compounds

The surface of CMK-3 carbon, synthesized by the reversible replication of mesoporous silica (SBA-15) using poly(furfuryl alcohol) as a carbon precursor, was activated by wet oxidation with an aqueous solution of HNO 3 or H 2 O 2 . The process was performed at 50°C using solution containing different concentrations of the oxidizing agent. It was found that during the modification no significant changes in textural and structural properties of CMK-3 replica occurred. However, the treatment resulted in the formation of appreciable amounts of surface species containing oxygen. XPS and DRIFT spectroscopy allowed to identify and quantify the surface functional groups. Their stability was studied by TG-FTIR measurements. CO and CO 2 were found as main gaseous products evolved during thermal decomposition under inert atmosphere. Finally, the modified samples were tested in the catalytic oxidative dehydrogenation * Corresponding author. Tel. +48 12 6632006. Fax +48 12 6340515. E-mail address: kustrows@chemia.uj.edu.pl (P. Kuśtrowski) 2 of ethylbenzene to styrene at 350°C in the presence of oxygen as an oxidizing agent (at O 2 /ethylbenzene molar ratio of 1.0 and 3.0). At the beginning of the catalytic run, the highest styrene yield and selectivity was achieved at the lower O 2 content over the catalysts treated with nitric acid. Nevertheless, all studied catalysts underwent a gradual deactivation due to coke formation and changes in the distribution of surface moieties.

One of the most efficient among the methods of managing waste tire rubber is the pyrolysis process which allows for obtaining pyrolysis oil. The as-received, raw tire pyrolysis oil (rTPO) is a complex mixture whose components exhibit a wide boiling temperature range, reflected in the physicochemical properties influencing injection, combustion, performance, and emission. The present contribution is aimed at producing TPO via steam-assisted pyrolysis followed by its fractionation by vacuum distillation. The resultant TPO fractions were analyzed in terms of composition as well as physicochemical parameters. The products are liquids with a relatively high density, poor volatility, and satisfactory low-temperature properties. They exhibit a mutually similar chemical composition reflected in a roughly the same Watson factor. The dominant components are cyclic and aromatic compounds, as was proven by gas chromatography coupled to mass spectrometry analysis and mid-infrared Fourier transform spectroscopy. Such a characteristic of the TPO fractions opens the way to utilize them either as additives to conventional automotive fuels or for heat and power generation. In particular, the two lightest fractions demonstrate high potential as fuel additives. Among the advantages of the fractionation of rTPO, one of the most important is the effect of the accumulation of sulfur-containing compounds in the highest boiling fractions, namely, vacuum fractionation allowed for reduction of the S content by 69.6 and 43.5 wt % (with regard to the rTPO) for the fractions boiling up to 180 and 180–250 °C, respectively. Thus, fractionation of pyrolysis oils could be used also as an ingenious and effective pretreatment method prior to exact desulfurization.

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Hydrothermal liquefaction of biomass in near-/supercritical water has attracted great attention in recent years. Although this technology seems to be promising for transformation of microalgal biomass, the information on the impact of feedstock and processing variables of continuous hydrothermal liquefaction on the properties of bio-oil provided in previous literature is scarce. Herein, the low-lipid Scenedesmus sp. biomass has been transformed to bio-oils through continuous hydrothermal liquefaction under various process conditions. The influence of temperature and residence time on bio-oil characteristic was discussed based on characterization by IR, GC-MS and gel permeation chromatography. The relative degree of branching of carbon chain of bio-oils components was estimated based on deconvolution of methyl and methylene IR absorption bands. The presumptive pathways of the reactions have been postulated. Finally, it was found that the parameters of bio-oil may be tailored by adjustment of processing variables, however, possible subsequent/parallel effects must be considered while designing the process.

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MCM-41-type mesoporous silica was used as a support for poly(furfuryl alcohol) deposition. This material was produced by precipitation-polycondensation of furfuryl alcohol (FA) in aqueous slurry of the SiO 2 support followed by controlled partial carbonization. By tuning the FA/MCM-41 mass ratio in the reaction mixture, various amounts of polymer particles were introduced on the inner and outer surface of the MCM support. The thermal decomposition of the PFA/MCM-41 composites was studied by thermogravimetry (TG) and spectroscopic techniques (DRIFT, XPS), whereas the evolution of textural parameters with increasing polymer content was investigated using low-temperature adsorption of nitrogen. The mechanism of thermal transformations of PFA deposited on the MCM-41 surface was discussed in detail. It was found that heating at a temperature of about 523 K resulted in opening of the furan rings and the formation of γ-diketone moieties, which were found to be * Corresponding author. Tel. +48-12-6632006; fax +48-12-6340515. E-mail address: kustrows@chemia.uj.edu.pl 2 the highest effective surface species for the adsorption of polar volatile organic compounds. A further increase in calcination temperature caused a drop in the amounts of surface carbonyls and the appearance of condensed aromatic domains.