
@article {Cagomoc_2016,
	title = {Enhanced chromium adsorption capacity via plasma modification of natural zeolites},
	journal = {Japanese Journal of Applied Physics},
	volume = {56},
	number = {1S},
	year = {2016},
	month = {nov},
	pages = {01AF02},
	publisher = {Japan Society of Applied Physics},
	abstract = {Natural zeolites such as mordenite are excellent adsorbents for heavy metals. To enhance the adsorption capacity of zeolite, sodium-exchanged samples were irradiated with 13.56 MHz capacitively coupled radio frequency (RF) argon gas discharge. Hexavalent chromium [Cr(VI)] was used as the test heavy metal. Pristine and plasma-treated zeolite samples were soaked in 50 mg/L Cr solution and the amount of adsorbed Cr(VI) on the zeolites was calculated at predetermined time intervals. Compared with untreated zeolite samples, initial Cr(VI) uptake was 70\% higher for plasma-treated zeolite granules (50 W 30 min) after 1 h of soaking. After 24 h, all plasma-treated zeolites showed increased Cr(VI) uptake. For a 2- to 4-month period, Cr(VI) uptake increased about 130\% compared with untreated zeolite granules. X-ray diffraction analyses between untreated and treated zeolite samples revealed no major difference in terms of its crystal structure. However, for plasma-treated samples, an increase in the number of surface defects was observed from scanning electron microscopy images. This increase in the number of surface defects induced by plasma exposure played a crucial role in increasing the number of active sorption sites on the zeolite surface.},
	doi = {10.7567/jjap.56.01af02},
	url = {https://doi.org/10.7567\%2Fjjap.56.01af02},
	author = {Charisse Marie D. Cagomoc and Magdaleno R. Vasquez}
}
