X-ray Absorption (XRA): A New Technique for the Characterization of Granular Activated Carbons

Materials

卷:14

ThaysetMariño Peacok¹  HaroldCrespo Sariol¹  ÁngelBrito Sauvanell²  JeamichelPuente Torres³  Jan Yperman⁴  Robert Carleer⁴  Peter Adriaensens⁴ 

[1] Faculty of Chemical Engineering, Applied Acoustic Laboratory, Universidad de Oriente, 90600 Santiago de Cuba, Cuba;

[2] Faculty of Chemical Engineering, Energetic Efficiency Center, Universidad de Oriente, 90600 Santiago de Cuba, Cuba;

[3] Faculty of Electrical Engineering, Universidad de Oriente, 90600 Santiago de Cuba, Cuba;

[4] Faculty of Sciences, Research group of Applied and Analytical Chemistry, Hasselt University, 3590 Diepenbeek, Belgium;

关键词: activated carbon;    X-ray absorption;    digital image processing;    adsorption;   

DOI  :  10.3390/ma14010091

来源: DOAJ

【 摘 要 】

The X-ray absorption (XRA) method using digital image processing techniques is a reliable technique to determine the exhaustion degree of granular activated carbons (GACs). Using an innovative digital image processing technique, the identification of individual adsorbed molecules or ions in a GAC was possible. Adsorption isotherm models (Langmuir and Freundlich) were used to simulate the adsorption equilibrium data of Methylene Blue (MB), nickel, cobalt and iodine. Freundlich equation was found to have the highest value of R² compared with Langmuir. The identification of distinctive patterns applying XRA for different adsorbed ions and molecules onto GAC was explored. It is demonstrated that unique XRA configurations for each adsorbed ion or molecule are found, as well as a proportional relationship between its incident energy (needed to achieve maximum photon attenuation) and the (effective) atomic number, the adsorbate mass and the molar or atomic mass of adsorbed molecule or ion. XRA method in combination with image histogram modifications was used to obtain a digital signature of adsorbed ions/molecules, giving distinct GSI values for each one in the used energy range. Probabilistic models prove that XRA results are within relationships between effective atomic number and photonic interaction probability, reinforcing the potentialities of XRA for monitoring (multi-)ion and/or molecule combinations on GAC using advanced digital image processing techniques. It was proved that the proposed approach could assess different adsorbed ions/molecules onto GACs in water purification systems.

【 授权许可】

Unknown