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[Display omitted] • Addition of cellulose acetate promotes the formation of chitosan/clay films. • Wastes from Tobacco Manufacture were transformed into bioinsecticide agents. • Ternary films are efficient in nicotine encapsulation and slowed release. • Nicotine release for increasing temperatures was monitored in situ by DRIFT. We report the engineering of insecticide films based on two mineral clays, montmorillonite and kaolinite, combined to chitosan and/or cellulose acetate originating from cigarette filter and subsequently impregnated with tobacco essential oil extracted from tobacco dust. Both binary composites, i.e. clay and chitosan or clay and cellulose acetate, and ternary composites containing clay, chitosan and cellulose acetate were prepared and characterized by XRD, DLS, ELS, and IR to investigate the nature of interactions within the composites. The two clay minerals showed different kinds of interaction with chitosan: intercalation in the case of Montmorillonite vs adsorption on the external surface for kaolinite. Secondly, the nicotine release from the composites films at different temperatures was studied by in-situ IR. The Montmorillonite composites, particularly the ternary one, showed a better encapsulation of nicotine which release was limited. Finally, the insecticidal activity of the composites was evaluated against the Tribolium castaneum a common wheat pest. The differences observed between montmorillonite and kaolinite composites were rationalized in relation to the nature of interaction between the components. The fumigant bioassay showed promising insecticidal effects in the case of the ternary composite cellulose acetate/chitosan/montmorillonite. Therefore, these eco-friendly nanocomposites can be used efficiently for the sustainable protection of stored cereals. [ABSTRACT FROM AUTHOR]

Highlights: [•] Optimization of multimeric enzymes immobilization on silanized silicon surface using a variety of bifunctional crosslinkers. [•] Influence of crosslinkers to preserve catalytic activity and thermo stability. [•] Comparison of the different crosslinkers in terms of the number of covalent bonds and the stability of the links formed upon grafting. [•] For multimeric enzymes, steric hindrance could be beneficial to stabilize dimers. [Copyright &y& Elsevier]

Energy recovery from lignocellulosic solid marine wastes, Posidonia oceanica wastes (POW) with slow pyrolysis responds to the growing trend of alternative energies as well as waste management. Physicochemical, thermogravimetric (TG/DTG) and spectroscopic (FTIR) characterizations of POW were performed. POW were first converted by pyrolysis at different temperatures (450 °C, 500 °C, 550 °C and 600 °C) using a fixed-bed reactor. The obtained products (bio-oil, syngas and bio char) were analyzed. Since the bio-oil yield obtained from POW pyrolysis is low (2 wt.%), waste frying oil (WFO) was added as a co-substrate in order to improve of biofuels production. The co-pyrolysis gave a better yield of liquid organic fraction (37 wt.%) as well as syngas (CH 4 , H 2 …) with a calorific value around 20 MJ/kg. The stoichiometric models of both pyrolysis and co-pyrolysis reactions were performed according to the biomass formula: C α H β O γ N δ S ε . The thermal kinetic decomposition of solids was validated through linearized Arrhenius model. [ABSTRACT FROM AUTHOR]

The hydrothermal synthesis of Mn-analcime was performed by mixing manganese(II) carbonate, silicic acid and aluminum nitrate in a basic medium in the 120-175 °C temperature range for 6-72 h. Different Mn/Al ratios were used. The obtained samples were characterized by powder XRD, N 2 physical adsorption analysis, TGA/DTA, transmission electron microscopy, elemental analysis, IR, XPS, EPR and 29 Si and 27 Al MAS-NMR spectroscopies. Manganese is probably mostly in the +IV oxidation state and partly substitutes silicon in the zeolite framework. The catalytic properties of Mn-analcime were evaluated in the cyclohexene oxidation reaction and highlight an interesting activity of this material, together with a good recyclability, which make it a promising catalyst for selective oxidation reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • n -Alkane hydrocracking is more negatively impacted with admixture of heavier cycloalkanes. • Cycloalkane adsorbs on metal sites more favorably than n -alkane with higher carbon number. • Larger alkanes impact cycloalkanes conversion only by preferred physisorption. Cycloalkanes are known to impact the metal–acid balance of the hydrocracking of n -alkanes with similar carbon number, however, how this impact varies with the carbon number of the components involved is still to be understood in more detail. For this purpose, the hydroconversion of n -octane and tert -butylcyclohexane, and n -decane and methylcyclohexane mixtures was investigated in this work over Pt/HUSY catalyst in both the ideal and the nonideal hydrocracking regime. Irrespective of the hydrocracking regime for pure n -octane, its conversion and isomer yields were significantly lowered upon admixture of tert -butylcyclohexane. On the other hand, n -octane admixture did not impact the tert -butylcyclohexane conversion nor its cyclic isomer yields. Upon methylcyclohexane admixture with n -decane, no impact was observed over the catalyst ensuring ideal hydrocracking of pure n -decane. Over the catalyst with significantly lower Pt loading, which does not ensure ideal hydrocracking of n -decane, methylcyclohexane lowered the n- decane conversion. A slightly negative impact of n -decane admixture on methylcyclohexane conversion was also observed. The observed effects are mainly attributed to the differences in adsorption strengths within the zeolite pores on top of differences in alkane and cycloalkane adsorption on the metal sites. [ABSTRACT FROM AUTHOR]