Utilization of near infrared spectroscopy for studying solvation properties of Cu-montmorillonites

作者：Brtanova Anna^*; Madejova Jana; Bizovska Valeria; Komadel Peter

来源：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 2014, 123: 385-391.

DOI：10.1016/j.saa.2013.12.022

• Near infrared spectroscopy
• Adsorption
• Acetonitrile
• Dimethylsulfoxide
• Montmorillonite
• Copper fixation

The benefit of near infrared (NIR) spectroscopy to follow the adsorption of dimethylsulfoxide and acetonitrile on reduced-charge Cu-montmorillonites differing in their chemical composition is presented. A NIR UpDRIFT accessory enabling measurement of spectra directly in closed glass vials was used to determine the amounts of adsorbed solvents. The area of the complex 2vCH band correlated very well with gravimetric analysis confirming that the UpDRIFT technique is suitable for studies of total content of organic solvents adsorbed on montmorillonites. Changes of the 2vOH band revealed that acetonitrile with a lower dipole moment (DP) and Gutmann donor number (GDN) fully solvated all samples heated up to 200 degrees C and only partially those heated at 300 degrees C, while DMSO with a higher DP and GDN completely solvated all the samples. These results indicate that fixation of Cu2+ cations in montmorillonites upon heating is a partially reversible process.

• 出版日期2014-4-5