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In this study, an investigation was carried out in order to determine the potential of ordered mesoporous carbon including high ratio sucrose in its composition as a CO2 adsorbent. Structural characterizations of silica and carbon material were determined by using a scanning electron microscope (SEM), N2 adsorption/desorption and X-ray diffraction (XRD) analysis. CO2 adsorption capacities of developed adsorbent at various temperatures (25°C, 35°C and 50°C) were determined by using a thermogravimetric analyzer under CO2 flow. The maximum adsorption capacity was obtained as approximately 2.27 mmol g CO2 g-1 adsorbent which was remained almost the same in the desorption process. The first order reaction kinetic model was well fitted with the experimental data. Arrhenius equation was used to calculate activation energy which was obtained as -2.86 kJ mol-1 indicating barrier-less type adsorption. Results showed that ordered mesoporous carbon could be a potential source for an efficient and low-cost adsorbent for CO2 capture.

In this study, the application of Sn/Sb/Ni-Ti electrodes for the treatment of waste streams were investigated which is promising for ozone production by electrolysis of water because of their stability and high potential for ozone evolution reaction. These series of anodes have a high electrochemical ozone generation potential at ambient conditions (approximately up to 40% current efficiency). But using and testing of these novel anodes for real wastewater are too limited in the literature. Titanium mesh substrate coated with Sn/Sb/Ni-Ti alloy was used as anode immersed in wastewater at room temperature with platinized titanium cathode. These electrodes used for COD and color removal from OID wastewater in Inegol, Bursa, Turkey. Five operational parameters were evaluated for electrochemical COD and color removal processes, such as pH, salt content, applied voltage/current, current efficiency and contact time. Experimental results showed that after 30 min the electrochemical oxidation efficiency of COD and color could reach up to 98% and 99% respectively at pH 8.2 and temperature of 25°C as the optimum conditions. Current density observed as the most effective parameter for COD and color removal efficiencies. The lowest energy consumption was between 10-25 mA cm-2 of current density with only 0.6 kWh gCOD−1, while the highest energy consumption was 100 mA cm-2 of current density with 9.12 kWh gCOD−1 . The optimum current density value has been found as 50 mA cm-2 with 4.05 kWh gCOD−1 . These results were also supported with ANOVA test.

In this study, the seasonal variation of atmospheric concentrations of PCDD/F and Dl-PCB and the effect of meteorological factors on concentration were investigated. Ambient air samples were collected monthly between May 2011 and October 2013 by using high volume samplers. Based on these samples, average PCDD/F and dl-PCB concentrations were obtained as 1482 fg/m3 and 4983 fg/m3 respectively. PCDD/F congeners did show seasonal variations. 58% share in total PCDD/Fs belongs to winter season while 4% to summer season. No significant seasonal change has been observed for dl-PCBs. 92% (1397 fg/m3) of PCDD/Fs were detected in particulate phase while 20% (926 fg/m3) of dl-PCBs were found in particulate phase. Strong negative correlations were obtained between all homolog groups and T, UV, SR. Correlation between five-chlorinated dl-PCBs, the most abandoned homolog group, with T, UV and SR generated positive meaningful correlation. No meaningful correlations were observed with other parameters. Correlations with particle phase were found to be more meaningful compared to gas phase for both PCDD/Fs and dl-PCBs.

In this study activated carbon is produced from areca plant leaves, an agricultural waste material. The physical and chemical structural characterisation of the prepared carbon was carried out by FTIR, TGA and XRD analysis. FTIR study showed the presence of several functional groups, such as C=O, C=C, OH, NH on the surface of the activated carbon. To determine the adsorption efficiency, studies were carried out using cationic and anionic dyes and it was found to be dependent on contact time, temperature and concentration of the solution. The experimental data obtained were correlated with the Langmuir, Freundlich isotherm model. Kinetic data were obtained using second order rate equation. Probable mechanism of adsorption process with the dyes was analysed. As the prepared carbon is cost efficient, abundant and has high uptake capacity, it can be used as an adsorbent for fresh water or waste water treatment. It could be considered as promising material for the removal of dyes.