Preparation, performances and reaction mechanism for the synthesis of H2O2 from H2 and O2 based on palladium membranes

Taking a critically informed approach, this innovative text examines emerging approaches to social procurement within the context of New Public Government (NPG), and examines the practices of social procurement across Europe, North America and Australia. Considering both the possibilities and limitations of social procurement, and the types of value it can generate, this book also provides empirically driven insights into the practicalities of 'triple bottom line' procurement, the related challenges of measuring social value and the management of both the strategic and operational dimensions of procurement processes. As such it will be invaluable reading for all those interest in social services, public governance and social enterprise

Human Computation and Convergence

Humans are the most effective integrators and producers of information, directly and through the use of information-processing inventions. As these inventions become increasingly sophisticated, the substantive role of humans in processing information will tend toward capabilities that derive from our most complex cognitive processes, e.g., abstraction, creativity, and applied world knowledge. Through the advancement of human computation - methods that leverage the respective strengths of humans and machines in distributed information-processing systems - formerly discrete processes will combine synergistically into increasingly integrated and complex information processing systems. These new, collective systems will exhibit an unprecedented degree of predictive accuracy in modeling physical and techno-social processes, and may ultimately coalesce into a single unified predictive organism, with the capacity to address societies most wicked problems and achieve planetary homeostasis.Comment: Pre-publication draft of chapter. 24 pages, 3 figures; added references to page 1 and 3, and corrected typ

The twelve principles of CO2 Chemistry

This paper introduces a set of 12 Principles, based on the acronym CO2 CHEMISTRY, which are intended to form a set of criteria for assessing the viability of different processes or reactions for using CO2 as a feedstock for making organic chemicals. The principles aim to highlight the synergy of Carbon Dioxide Utilisation (CDU) with the components of green and sustainable chemistry as well as briefly pointing out the connection to the energy sector

Unlocking the impact of electrode porosity on CO₂ splitting efficiency in porous DBD plasma reactors

The existence of non-thermal plasma within porous electrodes remains a topic of considerable debate within the scientific community. This study examines this phenomenon in CO2 splitting using a coaxial dielectric barrier discharge (DBD) reactor with a porous stainless steel (PSS) tube as the internal electrode. Four primary configurations were examined: smooth stainless-steel electrodes, porous electrodes with 0.2 µm and 0.5 µm pores diameter, and boehmite-coated porous electrodes, both with and without packing. A comprehensive range of gas flow rates (20–50 ml/min) and CO2 feed compositions were investigated. The CO2 conversion rates, specific energy input (SEI), and energy efficiency (η) were evaluated and compared across the configurations above. The findings revealed that the 0.5 µm porous electrode in an empty configuration achieved the highest CO2 conversion rate of 22.0 mmol CO2/h (CO2 conversion of 17.6 %) at a flow rate of 50 ml/min. The addition of argon to the feed gas resulted in enhanced CO2 conversion and energy efficiency, particularly in packed reactors. The boehmite-coated electrodes demonstrated an intermediate performance between the empty and packed configurations, combining the advantages of both. The superior performance of porous electrodes can be attributed to the intensified plasma interactions within the pores and amplified electric field effects at the electrode surfaces. This research underscores the potential of porous DBD reactors with optimised gas flows and electrode configurations to enhance CO2 conversion and energy efficiency. The use of porous electrodes, particularly when coated with boehmite, represents a promising avenue for the development of efficient plasma catalysts. This approach has the potential to reduce the costs associated with reactors and to increase conversion rates, thereby making it a viable option for the implementation of sustainable industrial processes.</p

Operando spectroscopy study of the carbon dioxide electro-reduction by iron species on nitrogen-doped carbon

The carbon–carbon coupling via electrochemical reduction of carbon dioxide represents the biggest challenge for using this route as platform for chemicals synthesis. Here we show that nanostructured iron (III) oxyhydroxide on nitrogen-doped carbon enables high Faraday efficiency (97.4%) and selectivity to acetic acid (61%) at very-low potential (−0.5 V vs silver/silver chloride). Using a combination of electron microscopy, operando X-ray spectroscopy techniques and density functional theory simulations, we correlate the activity to acetic acid at this potential to the formation of nitrogen-coordinated iron (II) sites as single atoms or polyatomic species at the interface between iron oxyhydroxide and the nitrogen-doped carbon. The evolution of hydrogen is correlated to the formation of metallic iron and observed as dominant reaction path over iron oxyhydroxide on oxygen-doped carbon in the overall range of negative potential investigated, whereas over iron oxyhydroxide on nitrogen-doped carbon it becomes important only at more negative potentials

Catalysis on nano-carbon materials: Going where to?

This introductory contribution to the special issue of Catalysis Today is dedicated to selected contributions presented at the Carbocat-IV (Carbon for Catalysis) Symposium held in Dalian (China) on November 7–10 (2010). The introduction first shortly overviews the main reasons for the interest on carbon materials for catalysis and the elements of novelty discussed on the contributions of this issue, and then provide a concise outline of the general trends and developments in this field to give a glimpse on the progresses in the field, and on the perspectives of this exciting area of catalysis

Use of Pt/CexZr1-xAl2O3 as Advanced Catalyst for Hydrogen Peroxide Thrusters

The capability of different Pt/Ce0.6Zr0.4/Al2O3 catalytic systems of effectively decomposing H2O2 has been studied in view of their application to monopropellant thrusters. BET surface area measurements, X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM) have been used together with catalytic tests in order to evaluate the advantages of using CeO2-ZrO2 mixed oxide solid solution as an alternative to current three ways catalysts (TWCs). From the assessment of alternative solutions, a Pt/Ce0.6Zr0.4/Al2O3 catalyst suitable to effectively decompose H2O2 has been identified. SEM-EDX analyses ruled out the occurrence of phase segregation and selective deposition of Pt on Zr during the catalyst preparation. No changes in the crystalline arrangement of the catalyst samples after H2O2 decomposition have been detected by XRD measurements, except for a slight crystallization or grain size growth as a consequence of the high temperatures experienced during the reaction...