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A kind of novel catalyst Co-Fe@GAC was prepared by the method of impregnation-calcination with cobalt and iron oxides attached onto granular activated carbon (GAC), and microscopic morphology and structure of the catalyst were analyzed by scanning electron microscopy and X-ray diffraction. Then the laboratory experiment was conducted focusing on examining the effects of degrading Rhodamine B (RhB), a representative organic pollutant, by peroxymonosulfate (PMS) that was activated by Co-Fe@GAC in different circumstances including co-existing ions and humic acids contained in the system. The experiment revealed that by increasing the dosage of Co-Fe@GAC catalysts and PMS concentration it could significantly improve the removal efficiency of RhB, and the system also showed a good degradation performance in a wide-range of pH, in addition, with interference resistance; and the oxidative species quenching test indicated that both hydroxyl radicals and sulphate radicals (SO4•-) existed in the Co-Fe@GAC/PMS system, and SO4•- was the dominant radical in RhB degradation. Besides, Co-Fe@GAC, being re-usable, was considerable stable in terms of catalytic performance. [ABSTRACT FROM AUTHOR]

Volatile organoamines are important industrial raw materials and chemicals. Long-term exposure to amines could be harmful to human health and even cause serious pollution. In this study, SnO2 decorated g-C3N4 material was fabricated and used as a sensor material for the detection of ethanolamine (EA). The structures, morphology, surface chemical states, and band structure were characterized, and gas sensing was studied. The results showed that SnO2 nanoparticles were dispersed on g-C3N4, and band structure was dependent on g-C3N4 doping. Notably, the interface heterojunction was conducive to electron transferring and O2 molecule adsorption; the formed reactive oxygen species enhanced the reaction between oxygen and EA, thus leading to high sensitivity to EA. This composite exhibited a high response that was 2.6 times higher than that of pure SnO2, and the detection limit reached 294 ppb. A g-C3N4/SnO2-based sensor displayed a high selectivity to EA with a fast response time (1 s) and recovery time (20 s) at low operating temperatures. In particular, this sensor exhibited a linear relationship between the response and concentration, which is required for quantitative analysis. [ABSTRACT FROM AUTHOR]