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COD (Chemical Oxygen Demand) and colour removals of around 60%, and 32% of total phenolic compounds degradation, were achieved in this work, showing the interest of this fungi in recalcitrant compound treatment. This study concluded that Assamra WWTP is efficient in removing caffeine and pharmaceutically active compounds (except for bisoprolol and carbamazepine) with overall efficiencies higher than 80%, whereas the wastewater treatment process was not able to eliminate antibiotics. Rapid urbanization and industrialization, together with new contaminants arising from many different sources, make it necessary to move forwards with research to face future challenges regarding water pollution. [Extracted from the article]

Different possible applications of ion exchange resins in the framework of biorefinery catalytic applications are discussed in this article. Three case studies were selected for this approach, connected to three main routes for biomass upgrading: syngas upgrading to high-value chemicals, biomass hydrolysate upgrading, and direct upgrading of oily fraction. The tailored acidic properties of these materials, as well as their stability in the presence of water, have made them promising catalysts for applications such as obtaining biodiesel from activated sludge wastes in batch reactors and obtaining polyoxymethylene methyl ether from syngas (via formaldehyde and methylal, and working in a continuous fixed bed reactor). However, the acidity of these materials may still be too low for acid-catalyzed aldol condensation reactions in the aqueous phase. [ABSTRACT FROM AUTHOR]

Secondary sludge from municipal wastewater treatment plant is proposed as a promising alternative lipid feedstock for biodiesel production. A deep study combining different type of raw materials (sludge coming from the oxic, anoxic and anaerobic steps of the biological treatment) with different technologies (liquid–liquid and solid–liquid extractions followed by acid catalysed transesterification and in situ extraction-transesterification procedure) allows a complete comparison of available technologies. Different parameters – contact time, catalyst concentration, pretreatments – were considered, obtaining more than 17% FAMEs yield after 50 min of sonication with the in situ procedure and 5% of H 2 SO 4 . This result corresponds to an increment of more than 65% respect to the best results reported at typical conditions. Experimental data were used to propose a mathematical model for this process, demonstrating that the mass transfer of lipids from the sludge to the liquid is the limiting step. [ABSTRACT FROM AUTHOR]

BACKGROUND Pre-concentration of two different emerging pollutants - an endocrine disruptor and a chlorinated paraffin - was carrxbied out by adsorption/desorption cycles onto carbonaceous materials - activated carbon (GF-40), multiwall carbon nanotubes (MWCNT) and a high surface area graphite (HSAG-500). The breakthrough curves were modeled by Bed Depth Service Time (BDST), Thomas and Yoon-Nelson models. RESULTS MWCNT presents for both compounds the highest normalized adsorption capacity. Although GF-40 offers 100% elution efficiency, no pre-concentration was obtained with this adsorbent. In contrast, pre-concentration was reached with MWCNT and HSAG-500. The best results were obtained with MWCNT, with a pre-concentration factor of 3.4 for 1,8-dichlorooctane and 2.8 for 2-(4-methylphenoxy)ethanol. BDST and Thomas models can predict the adsorption capacity and Yoon-Nelson the time required to reach the 50% adsorbate breakthrough. CONCLUSIONS Pre-concentration was reached using MWCNT and HSAG-500 as adsorbent. MWCNT is the best adsorbent, since this material presents the highest normalized adsorption capacity and concentration factor. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The photocatalytic TiO 2 -assisted decomposition of 2-(4-methylphenoxy)ethanol (MPET) in aqueous solution has been studied for the first time. The intermediate compounds of MPET photodegradation have been also determined. A toxic p-cresol is formed in significant quantities during the photocatalytic reaction. A solvent-exchange approach for a template-free preparation of spherical TiO 2 particles has been described, which is based solely on precipitation of hydrous titania from aqueous titanium peroxo complex by using organic solvents. The proposed method favours the formation of spherical titania particles with a mean size varying from 50 to 260nm depending on the choice of solvent. The procedure for converting nonporous titania spheres into mesoporous material maintaining the same spherical morphology has been developed. The synthesized TiO 2 spheres demonstrate a degree of MPET photo-degradation close to that of the commercial titania Aeroxide P25, besides being successfully recovered and reused for four reaction cycles without loss of photocatalytic activity. The effectiveness of the commercial Aeroxide P25 in MPET photodegradation, on the other hand, suffers 10-time drop during the third reaction cycle, which is attributed to its poor recoverability because the photocatalyst is composed of small particles of 20nm size., (Copyright © 2017 Elsevier B.V. All rights reserved.)