Platinum supported on highly-dispersed ceria on activated carbon for the total oxidation of VOCs

Catalysts consisting in platinum supported on cerium oxide highly dispersed on activated carbon, with a Pt loading of 1 wt.% and ceria loadings of 5, 10 and 20 wt.% have been prepared by impregnation method and characterized by several techniques (N2 adsorption at 77 K, ICP, XRD, H2-TPR and XPS). Their catalytic behavior has been evaluated in the total oxidation of ethanol and toluene after reduction at 473 K. The obtained results show that the prepared catalysts have better performances than platinum supported on bulk CeO2. The best catalytic performance was obtained for 10 wt.% ceria loading, likely due to an optimum synergistic interaction between highly dispersed cerium oxide and platinum particles. Pt-10Ce/C achieves total conversion of ethanol and toluene to CO2 at 433 K and 453 K, respectively, and shows no deactivation during a test for 100 h. Under humid conditions (relative humidity, RH, of 40 and 80%), the activity was only slightly influenced due to the hydrophobic character of the activated carbon support, which prevents the adsorption of water.Financial support from Generalitat Valenciana (Spain, PROMETEO/2009/002-FEDER and PROMETEOII/2014/004) is gratefully acknowledged

Effect of the metal precursor on the properties of Pt/CeO2/C catalysts for the total oxidation of ethanol

Two series of ceria-promoted carbon-supported platinum catalysts have been prepared and evaluated in total oxidation of ethanol, as a model volatile organic compound (VOC), in order to study the effect of the metal precursor (H2PtCl6 or Pt(NH3)4(NO3)2) on their physico-chemical properties and catalytic behavior. Catalysts with Pt loading of 1 wt.% and ceria loading of 5, 10 and 20 wt.% have been prepared by the impregnation method, and characterized by several techniques (N2 adsorption at 77 K, ICP, XRD, H2-TPR and XPS). Toluene hydrogenation has been used to obtain an estimation of the platinum dispersion on the investigated catalysts. On the other hand, their catalytic behavior has been evaluated in the total oxidation of ethanol, selected as a VOCs probe molecule. A much higher catalytic activity and selectivity to CO2 was achieved with chlorinated catalysts. This behavior has been correlated with a high platinum dispersion and a strong metal–CeO2 interaction in these catalysts which promotes their redox properties.Financial support from Generalitat Valenciana (Spain, PROMETEO/2009/002-FEDER and PROMETEOII/2014/004) is gratefully acknowledged

Anaerobic co-digestion of pear residues and sewage sludge using a CSTR digester. Influence of the feed procedure

Anaerobic co-digestion of pear residues with sewage sludge is feasible. Important differences are obtained from the two feed regimes tested, with better results for the so-called continuous feed. The organic loading rate (OLR) is the important parameter for the methane productionUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Activated Carbons Impregnated with Na2S and H2SO4: Texture, Surface Chemistry and Application to Mercury Removal from Aqueous Solutions

The effects of treatment of an activated carbon with Sulphur precursors on its textural properties and on the ability of the complex synthesized for mercury removal in aqueous solutions are studied. To this end, a commercial activated carbon has been modified by treatments with aqueous solutions of Na2S and H2SO4 at two temperatures (25 and 140 °C) to introduce sulphur species on its surface. The prepared adsorbents have been characterized by N2 (-196 °C) and CO2 (0 °C) adsorption, thermogravimetric analysis, temperature-programmed decomposition and X-ray photoelectron spectroscopy, and their adsorption capacities to remove Hg(II) ions in aqueous solutions have been determined. It has been shown that the impregnation treatments slightly modified the textural properties of the samples, with a small increase in the textural parameters (BET surface area and mesopore volumes). By contrast, surface oxygen content was increased when impregnation was carried out with Na2S, but it decreased when H2SO4 was used. However, the main effect of the impregnation treatments was the formation of surface sulphur complexes of thiol type, which was only achieved when the impregnation treatments were carried out at low temperature (25 °C). The presence of surface sulphur enhances the adsorption behaviour of these samples in the removal of Hg(II) cations in aqueous solutions at pH 2. In fact, complete Hg(II) removal is only obtained with the sulphur-containing activated carbons.The financial support by Generalitat Valenciana, Spain (PROMETEO/2009/002) is gratefully acknowledged

Effect of NaHCO3 addition on the anaerobic co-digestion of fruit and vegetable waste and sewage sludge performance

Digestion of FVW residues with sewage sludge is feasible as long as the FVW to sludge ratio fed to the batch digester is not too large. The pH is the main variable determining the reactor performance and can be controlled by NaHCO3 addition.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Effect of the feed procedure on production of biogas from anaerobic digestion of pear residues using a CSTR Digester

The anaerobic digestion for the production of biogas is one of the best alternative management procedures of the fruits and vegetables wastes (FWV) since it simultaneously allows energy recovery and material recycling if the digestate can be used for soil amendment. Nevertheless, the generation of this kind of residues is frequently concentrated in only few weeks per year, imposing a serious economic limitation. Thus, introduction of the FVW into the anaerobic digester of the municipal wastewaster treatment plant (MWTP) is a very interesting approach. The aim of this work was to investigate the digestion of pear residues using the anaerobic sludge obtained from a MWTP digester under mesophilic conditions and to explore the influence of the feed operating conditions using a continuously stirred tank reactor (CSTR) digester. The results indicate that the continuous feed allows the treatment of almost twice as much residue (10.5 vs 6.0 g L–1 d-1). System instabilities are observed at larger OLRs.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Influence of alkalinity addition on biomethanization of fruit and vegetable waste and sewage sludge performance. Batch study

Fruit and vegetable wastes (FVW) are generated in large quantities around the world. This kind of residue constitutes a source of nuisance in municipal landfills because of its high biodegradability. Their high moisture and large biodegradable organic matter content facilitates their treatment by biological techniques among which the anaerobic digestion presents increasing attention. This alternative allows the recovery of energy and a solid product that can be used as an amendment for soils. In this work, we study the possibility of management of Fruit and Vegetable Wastes (FVW) through their simultaneous digestion with the primary sludge of Municipal Wastewater Treatment plants. Results indicate that feed to inoculum ratios and the pH control are the main variables determining the methane yields. The results for a ratio of 50% sludge together with 10 g NaHCO3/kg of residue are among the best obtained, with a methane yield of about 90 L per kg of volatile solids, and a methane concentration of 40% (v/v) of the biogas.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Theoretical investigation of the design and performance of a dual energy (kV and MV) radiotherapy imager

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134977/1/mp5120.pd

Saving and reproducing the nation: Struggles around right-wing politics of social reproduction, gender and race in austerity Europe

This article suggests the analytic lens of cultural, social and national reproduction to understand the centrality of gendered and ethnic relations, in particular a focus on family life in contemporary UK. Proposing a theoretical focus on reproduction, the article then provides some contextualisation with wider European experiences to show connections between the political articulations across the far-right and mainstream right-wing. It argues that there is much overlap between the far-right and mainstream rightwing, conservative gender and family ideologies, where contradictory aspects of their gender and family ideals (simultaneously progressive and traditional) are articulated as care for the nation's future. Care is then articulated for the purpose of racist activism and constructing governmental belonging. The racialized migrant family plays a central role in these debates, marking the boundaries of the nation. The article explores these issues in depth through the example of material and symbolic constructions of the racialized migrant family as undeserving of care, exemplified through the UK policy of No Recourse to Public Funding

Do Bat Gantries and Underpasses Help Bats Cross Roads Safely?

Major roads can reduce bat abundance and diversity over considerable distances. To mitigate against these effects and comply with environmental law, many European countries install bridges, gantries or underpasses to make roads permeable and safer to cross. However, through lack of appropriate monitoring, there is little evidence to support their effectiveness. Three underpasses and four bat gantries were investigated in northern England. Echolocation call recordings and observations were used to determine the number of bats using underpasses in preference to crossing the road above, and the height at which bats crossed. At gantries, proximity to the gantry and height of crossing bats were measured. Data were compared to those from adjacent, severed commuting routes that had no crossing structure. At one underpass 96% of bats flew through it in preference to crossing the road. This underpass was located on a pre-construction commuting route that allowed bats to pass without changing flight height or direction. At two underpasses attempts to divert bats from their original commuting routes were unsuccessful and bats crossed the road at the height of passing vehicles. Underpasses have the potential to allow bats to cross roads safely if built on pre-construction commuting routes. Bat gantries were ineffective and used by a very small proportion of bats, even up to nine years after construction. Most bats near gantries crossed roads along severed, pre-construction commuting routes at heights that put them in the path of vehicles. Crossing height was strongly correlated with verge height, suggesting that elevated verges may have some value in mitigation, but increased flight height may be at the cost of reduced permeability. Green bridges should be explored as an alternative form of mitigation. Robust monitoring is essential to assess objectively the case for mitigation and to ensure effective mitigation