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The performance of carbon-supported cobalt catalysts was compared with that of Co/γ-Al2O3 reference catalysts for the Fischer–Tropsch synthesis (FTS) reaction. The carbon support (CS) was prepared using a hydrothermal method that formed mostly spherical ∼300–800 nm carbons that were first carbonized at 900 °C and then partially graphitized at 1900 °C. The FTS study was conducted using a continuously stirred tank reactor, and the cobalt catalysts were promoted with Pt (0.2% Pt–10% Co) to facilitate the reduction of cobalt oxides. Catalysts were prepared by an evaporative method (Co/CS-IWI) and by a chemical vapor deposition technique (Co/CS-CVD). The CVD technique led to a higher CO conversion (26.5%) relative to the conventional evaporative (IWI) method (7.4%) at the same temperature (220 °C) and space velocity (1.5 NL/gcath). Remarkably, the Co/CS-CVD displayed a high oxygenate selectivity (∼10%) in comparison with cobalt alumina catalysts (i.e., including one having similar Pt and Co loadings, as well a...

Solvent degradation and metal corrosion are critical concerns of a post-combustion CO2 capture process. Systemic analysis indicated that oxidation, nitrosation, and corrosion reactions occur or initiatethrough a radical reaction and thus addition of a radical scavenger is expected to work effectively to avoid these reactions. Here, for the first time, a multifunctional organic compound (CAER additive) has been evaluated as an inhibitor. The corrosion rate of A106 in 5 mol/kg MEA was lowered by one order of magnitude when 5 mM inhibitor was added. Oxidation of 5 mol/kg MEA was monitored based on accumulation of formate concentration in the solution and formate levels were below the detection limit when CAER additive was present. Furthermore, the same additive was found to inhibit nitrosation of 5 mol/kgmorpholine with 100 ppm of NO2 gas by 91% in 6 h.

Lithium-ion batteries are increasingly ubiquitous in portable consumer electronic devices, including laptop computers, cellular phones, and tablet computers. Lithium-ion batteries are also finding widespread deployment in many additional applications and settings, including underground mining environments, where lithium-ion batteries are used as electrochemical power sources for cap lamps, and in tracking and communications equipment.1,2 Battery safety is of paramount importance in any portable electronic device regardless of setting, and is particularly significant in enclosed and isolated areas such as passenger aircraft, or in underground mining environments, where potentially explosive methane/air mixtures can be ignited by a simple spark, which can be caused by shorting and thermal runaway of lithium-ion batteries. This presentation will summarize systematic abuse testing of different lithium-ion batteries used in underground mining safety and communication equipment, including lithium cobalt oxide (LiCoO2), lithium nickel manganese cobalt oxide (NMC), and lithium iron phosphate (LiFePO4) based cathode chemistries. Prismatic and cylindrical 18650 lithium-ion batteries were obtained from commercial vendors and subjected to both wedge and flat plate crush tests, in order to determine the relative safety of each cathode chemistry under two crush speeds and various states-of-charge (SOC). Battery voltage, case temperature and applied load were recorded for each crush test. Video recording of each crush test was also collected. In some cases, hard or soft electrical short circuits were caused by crushing the battery, resulting in thermal runaway, rapid temperature increases, and explosions or fires. Correlations will be drawn between choice of cathode chemistry, state-of-charge, type of crush test, and choice of atmosphere (air or methane/air mixtures), in order to determine the most suitable lithium-ion battery chemistry for underground mining applications. References 1) Dubaniewicz, T. H. Jr.; DuCarme, J. P. Journal of Loss Prevention in the Process Industries. 2014, 32, 165. 2) Dubaniewicz, T. H. Jr.; DuCarme, J. P. IEEE Transactions on Industry Applications. 2013, 6, 2451-2460.

Redox flow batteries (RFBs) are an emerging technology suitable for large-scale, stationary energy storage applications, including grid storage. Redox flow batteries are capable of storing high amounts of both energy (MWh) and power (MW).1 One principle advantage of flow batteries is the ability to decouple the energy density and power density of the system, and scale both independently. The all-vanadium RFB represents the current state-of-the-art in flow battery technology, and features several advantages, including rapid response times, high depth of discharge, long cycle life, and good cell performance metrics (i.e. efficiencies). Anolyte and catholyte cross-contamination is eliminated through the use of the same active metal cation in both compartments of the cell. Issues associated with the vanadium RFB include a low cell voltage (1.26 V), the use of expensive membranes including Nafion®, and the relatively high cost of vanadium, leading to expensive electrolytes.2 The development of anolytes with higher reversible potentials than VO2+/VO2 +, along with electroactive species featuring higher natural abundance and lower cost than vanadium, represents an attractive alternative to vanadium-based anolytes. Flow battery anolytes based on the Mn2+/Mn3+ redox couple have been reported in the literature, and the high standard electrode potential of Mn2+/Mn3+ (1.51 V) has been utilized in manganese anolyte (Mn2+/Mn3+)/vanadium catholyte (V2+/V3+) redox flow batteries, featuring a theoretical open circuit voltage of 1.77 V.2,3 The usage of manganese anolytes can lead to higher cell voltages (Figure 1) and cheaper anolytes, but the disproportionation reaction of Mn3+ to Mn2+ and MnO2 is a technical issue that needs to be resolved in order for manganese-based anolytes to find widespread utility in redox flow batteries.2 This presentation will disclose our investigations on the development of manganese-based anolytes for redox flow batteries. The effect of various additives on electrolyte stability and electrochemical kinetics for the Mn2+/Mn3+ redox couple will be quantified using cyclic voltammetry, RDE measurements, electrochemical impedance spectroscopy, overpotential measurements, and full-cell testing (constant current charge/discharge) of Mn/V redox flow batteries (Figure 2). References 1) Wang, W. et al. J. Power Sources. 2012, 216, 99. 2) Xue, F.-Q. et al. Electrochimica Acta. 2008, 53, 6636. 3) Hong, T.; Xue, F. “Investigation on manganese (Mn2+/Mn3+)-vanadium (V2+/V3+) redox flow battery.” 2009 Asia-Pacific Power and Energy Engineering Conference (APPEEC).

Electrochemical double layer capacitors (EDLCs), are energy storage devices featuring many advantages, including long cycle life, low internal resistance, and high power densities (i.e. fast charge/discharge rates). Due to these advantages EDLCs have drawn much attention recently, and have been applied to electric/hybrid vehicles, heavy-construction equipment, electronics, and grid utility storage. The most common electrode material for EDLCs is porous activated carbon with the advantages of low cost, abundant resources, and simple processing. In this present work, carbon materials for EDLCs were hydrothermally synthesized from low-cost bio-polymer precursors. Hydrothermal synthesis (HTS) uses simple equipment and runs under mild conditions; the process also uses environmentally friendly precursors and does not produce any hazardous waste. HTS provides a facile method for the development of inexpensive, high- performance carbon materials. In this work, low cost precursors were obtained locally. The precursors were ground and mixed with DI water, and the solution was then sealed in a Teflon lined pressure vessel. The pressure vessel was heated to 200 °C for 24 hours. After the reactor cooled down, the as-synthesized carbons were harvested by filtration and dried in an oven at 120 °C overnight. The morphology of the as-synthesized carbons was characterized by scanning electron microscopy (SEM) as shown in Figure 1. The as-synthesized carbons went through a one-step activation, which increased the surface area to over 1000 m2/g, with 70% micro porosity. Electrodes were made, and tested in 1.8M TEMABF4in PC and 38% sulfuric acid. Cyclic voltammetry (CV) and galvanostatic charge-discharge tests were run on these activated carbons to study the electrochemical performance. The activated carbons showed very nice capacitor characteristics such as rectangular CV curves and very fast charge-discharge rates in both organic and aqueous electrolytes, as shown in Fig 2. The specific capacitance of these materials in organic electrolyte was ~90-120 F/g and had a volumetric capacitance of ~40-60 F/cc, while in aqueous electrolyte the gravimetric capacitance ranged from 180-200 F/g and 100-120 F/cc.

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