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Reaction of VCl3 with potassium 1,3-diamino-2-propanol-N,N,N′,N′-tetraacetate gave a dinuclear complex K2[V2(dpot)2]·7H2O. X-Ray crystal structure analysis revealed that each vanadium atom in the complex adopts pentagonal-bipyramidal seven-coordination. The dpot4− ion contains a deprotonated alkoxy group, which bridges the two vanadium atoms, and a pendant carboxylic acid group.

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Hexaammineruthenium (III) [Ru(NH3)6]3+-Nafion®-isopropanol diluted films were spin coated on indium tin oxide (ITO)-coated glass substrates. The fabricated samples were used to determine the presence of lead and cadmium in solution using anodic strip-ping voltammetry (ASV). The calibration sensitivity of the electrodes for lead and cadmium were approximately equal. Detection limits of 5ppb and 4ppb were determined for lead and cadmium respectively. Real sampling tests with commercially available yellow water color yielded 0.7106 ppm of Pb with ASV. The result was verified with atomic absorption spectrometry (AAS) which yielded 0.6923ppm of Pb.

Several coin cells with cathode materials ranging from stainless steel, magnesium persulfate, and magnesium persulfate/reduced graphene oxide (rGO), as well as a novel electrolyte, were fabricated and assembled. They were characterized using scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), and voltammetry to determine surface morphology, elemental composition, and electrochemical characteristics, respectively. The amount of the additive, rGO, was verified by analyzing the current response after 10 consecutive scans via cyclic voltammetry. The optimum amount which only had a 19% decrease from cycle 2 to cycle 9 was from the cathode electrode which had 4mg rGO. However, galvanostatic charge-discharge measurements showed that the coin cells had no ability to hold the charge after cycling. The coin cell which contained the optimized cathode electrode was dismantled for further surface and elemental analysis. After a scan, some of the cathode material was converted to its reduction product magnesium sulfate (MgSO4) and failed to revert back to its original persulfate form which signified irreversibility. Contaminants were found on the surface of the anode and corrosion were observed on the surface of the current collector which denotes instability of the components with the chosen electrolyte. The reactivity of the components with each other was also predicted by previous studies.

Due to the continued increasing levels of CO2 emissions that is contributing to climate change, CO2 mitigation technologies, particularly carbon capture and storage, are being developed to address the goal of abating CO2 levels. Carbon capture technologies can be applied at the pre-combustion, oxy-fuel combustion, and post-combustion stages, the latter being the most widely used due to its flexibility. Among the several CO2 separation processes available for carbon capture, absorption is the most widely used where amine solutions are used as absorbents. This paper highlights the use of a wetted wall column fabricated by Siy and Villanueva (2012) and simulated flue gas to determine the performance of CO2 absorption in terms of the percentage of CO2 absorbed, the steady state time, and the overall gas mass transfer coefficient. The concentrations used were 1, 5, 10, and 15% NH3(aq) at a constant temperature range of 12-17ºC, solvent flow rate of 100 mL/min, and simulated flue gas flow rate of 2 L/min. It was found that increasing the solvent concentration resulted in a proportional increase both in the percentage of CO2 absorbed and the overall gas mass transfer coefficient. The average percentage of CO2 absorbed ranged within 52.25% to 95.29% while the overall mass transfer coefficient ranged from 0.1843 to 0.7746 mmol/m2∙s∙kPa. However, erratic behavior was seen for the time required for the system to reach steady state. Using Design ExpertTM for analysis, the results showed that the effect of varying the concentration had a significant effect on the percentage of CO2 absorbed and the overall gas mass transfer coefficient. The results proved that the greater the aqueous ammonia concentration, the greater the percentage of CO2 absorbed. The range of 5-10% aqueous ammonia is recommended because the percentage of CO2 absorbed peaks at an average of 92% beyond the range of 5-10%.

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