The complexity of composition of bio‐oil from biomass makes it difficult to produce upgraded bio‐oil via hydrodeoxygenation. In this paper, acetone is thus considered as a model compound of the ketones family abundant in pyrolysis bio‐oil. Results showed that high conversion rates of acetone between 86.6% and 91.9% were observed with the use of HZSM‐5, 5% Ni2P/HZSM‐5, and 10% Ni2P/HZSM‐5 catalysts. In most cases, CO2, C2H6, C3H6, and C3H8 were the dominant non‐condensable gas products. For liquid phase, the selectivity was evaluated for different catalysts relative to ethanol, acetaldehyde, and aromatic hydrocarbons. A lower temperature favoured the formation of acetaldehyde and methyl isobutyl ketone with the 5% Ni2P/HZSM‐5 catalyst, while higher temperatures increased the proportion of aromatic hydrocarbons. The principal influencing parameters of acetone HDO were temperature and contact time followed by reaction pressure and H2 partial pressure. Optimal conditions give a selectivity of 49% of aromatics (benzene, toluene, and xylene) with the use of the 5% Ni2P/HZSM‐5 catalyst. The pathway of the main reactions of acetone HDO was also proposed. MIK and aromatic hydrocarbons were formed by a multiple step aldol condensation reaction of acetone molecules followed by further hydrogenation.

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The present work addresses the development of simple, low-cost and eco-friendly cocoa-shell-based materials for efficient removal of heavy metal hexavalent chromium (Cr(vi)), and toxic nitrate (NO3−) from aqueous solution.

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The fate of the antimicrobial compounds in the environment is of great interest since their presence in the aquatic systems has raised environmental problems. More and more chemicals of this class are treated as emerging contaminants. The degradation of these compounds may result in the formation of a wide array of metabolites which can be more toxic than the parent substrate. Therefore, precise elucidation of all possible transformation products as well as a thorough study of their physico-chemical and biological properties is of great importance. The present work deals with the study of the photochemical behavior of sulfamethoxazole from the kinetic aspect as well as the elucidation of the products arising from the solar irradiation of the antimicrobial sulfamethoxazole in the aqueous solutions. HPLC/MS and HPLC/MS/MS with accurate mass measurements were used for this purpose. stainless steel equipped with two germicidal lamps (Mazda T815 15W) emitting selectively at 254 nm and symmetrically installed around the cylinder were used. The reactor, a quartz tube (d=2.5 cm) containing a maximum of 50 mL solution, was located in the centre of the container.The disappearance of the antimicrobial and the formation of the products were followed by high performance liquid chromatography using a Waters 2695 HPLC (Alliance) chromatograph system equipped with a Waters 2998 photodiode array detector. The experiments were performed by UV detection at either 250 nm or 280 nm and by using a reverse phase Nucleodur column (Macherey-Nagel, 100-5 C18 ec; 150-4.6 mm). The flow rate was 1.0 mL min -1 and the injected volume was 50 µL. The elution was accomplished with water, formic acid (0.1%) and acetonitrile (60/40 v/v). A Waters/Micromass LC/QTOF tandem mass spectrometer (Micromass, Manchester, UK), with an orthogonal geometry Z-spray ion source, was used for LC/ESI/MS and LC/ESI/MS/MS experiments. LC separation was performed using the gradient program reported in the literature [19]. Eluate was subjected to electrospray ionization (ESI) in the positive ion as well as negative mode and resulted in the formation of protonated molecules and deprotonation of the sample components. Scanning was performed in the range between m/z 60 and 600. The elemental composition of the recorded ions was further determined using MassLynx Elemental Composition software V4.1 (Micromass). C, H, N, O and S were selected as possible elements present. In LC/MS analyses, in order to assign the elemental formulas, the minimum and maximum atoms of each element were set as follows: C from 1 to 20; H from 1 to 20; N from 0 to 5; O from 0 to 10 and S from 0 to 2. No nitrogen rule, ring and double bond equivalents were applied. The maximum deviation was set to 10 ppm. Five scans were combined before the integration of the

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<p>Abstract</p><p>Water pollution has long been considered a major problem causing environmental and public health issues. A range of contaminants are encountered in wastewater, industrial effluents and also road runoff, they include total suspended solids, nutrients, hydrocarbons and heavy metals. These latter have been found very toxic and hazardous, either for human health, or fauna and flora. In recent decades, studies have demonstrated a good removal efficiency of heavy metals by adsorption technique, and especially biosorption. Numerous biosorbents have been investigated, mainly lignocellulosic materials which have shown high adsorption capacity. Within this context, this study aims to investigate flax fibers capacity of zinc, copper and lead ions removal from aqueous solutions, in order to examine the best conditions to test a full-scale device designed to treat stormwater runoff. The choice of flax is related to its high availability, low cost and local economy reasons. The device consists of sand and layers of flax fibers geotextiles. It will be placed on a parking at the entrance of a retention basin in Le Havre. For this purpose, batch experiments were carried out with ternary and mono-metal solutions of zinc, copper and lead ions at room temperature with molar concentrations of 0.04 mmol.l<sup>-1</sup>, at pH around 6.4. Biosorption kinetics and biosorption equilibrium were performed and analyzed. The results showed a favorable adsorption for the three metals in the order Pb > Cu > Zn for both types of solutions, with adsorption rates of 94%, 75% and 62% respectively in the ternary metal solution and 94%, 81% and 82% in the mono-metal solutions. The effect of competition was important for zinc, barely visible for copper, and non-existent for lead.</p><p>Keywords: Biosorption, heavy metals, pollutants, stormwater management systems.</p><p> </p>

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