237 research outputs found

    Activated Carbon Modified with Copper for Adsorption of Propanethiol

    Get PDF
    Activated carbons were characterized texturally and chemically before and after treatment, using surface area determination in the BET model, Boehm titration, TPR, DRX and immersion calorimetry. The adsorption capacity and the kinetics of sulphur compound removal were determined by gas chromatography. It was established that the propanethiol retention capacity is dependent on the number of oxygenated groups generated on the activated carbon surface and that activated carbon modified with CuO at 0.25 M shows the highest retention of propanethiol. Additionally is proposed a mechanism of decomposition of propenothiol with carbon-copper system

    Graphenes as Metal-Free Catalysts with Engineered Active Sites

    Full text link
    [EN] This Perspective article highlights how recent discoveries on the activity of defective graphene to promote different organic reactions as metal-free catalysts has led to propose certain substructures present on these defective graphenes as active sites. The sustainability of using as catalysts graphenes obtained from biomass and the possibility to generate active sites by introducing defects on the sheet are the two main characteristics triggering research in this area. Emphasis is made in the need to gain understanding on the nature of the active sites and how this understanding requires the combination of conventional kinetic experiments as well as advanced characterization tools. The relationship between catalysis by graphene and that by organocatalysis has also been remarked.Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa, Grapas, and CTQ2015-69153-CO2-1) and Generalitat Valenciana (Prometo 2013-014) is gratefully acknowledged. A.P. also thanks the Spanish Ministry of Economy and Competitiveness for a Ramon y Cajal research associate contract.Primo Arnau, AM.; Parvulescu, V.; GarcĂ­a GĂłmez, H. (2017). Graphenes as Metal-Free Catalysts with Engineered Active Sites. The Journal of Physical Chemistry Letters. 8(1):264-278. https://doi.org/10.1021/acs.jpclett.6b01996S2642788

    Review of biochar role as additive in anaerobic digestion processes

    Get PDF
    because of the urgent need to provide renewable energy sources and efficiently manage the continuously growing amount of organic waste. Biochar (BC) is an extremely versatile material, which could be produced by carbonization of organic materials, including biomass and wastes, consistently with Circular Economy principles, and “tailor-made” for specific applications. The potential BC role as additive in the control of the many wellknown critical issues of AD processes has been increasingly explored over the past few years. However, a clear and comprehensive understanding of the connections between BC and AD is still missing. This review paper analyses and discusses significant references (review articles, research papers and international databases and reports), mostly published in the last 10 years. This review is aimed at addressing three key issues related to the better understanding of the BC role in AD processes: 1. Investigation of the influence of BC properties on AD performances and of their ability to counteract its main challenges; 2. Assessment of the optimal BC production chain (i.e. feedstock-pyrolysis-activation) to achieve the desired features; 3. Evaluation of the economic and environmental advantages connected to BC use in AD processes, compared to conventional solutions applied to address AD challenges
    • …
    corecore