title: Utilization of near infrared spectroscopy for studying solvation properties of Cu-montmorillonites.
abstract: 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 2νCH 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 2νOH band revealed that acetonitrile with a lower dipole moment (DP) and Gutmann donor number (GDN) fully solvated all samples heated up to 200°C and only partially those heated at 300°C, while DMSO with a higher DP and GDN completely solvated all the samples. These results indicate that fixation of Cu(2+) cations in montmorillonites upon heating is a partially reversible process.
authors.affiliation: Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia. Electronic address: anna.brtanova@savba.sk.
authors.forename: Anna
authors.initials: A
authors.lastname: Brtáňová
authors.affiliation: Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia. Electronic address: jana.madejova@savba.sk.
authors.forename: Jana
authors.initials: J
authors.lastname: Madejová
authors.affiliation: Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia. Electronic address: valeria.bizovska@savba.sk.
authors.forename: Valéria
authors.initials: V
authors.lastname: Bizovská
authors.affiliation: Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia. Electronic address: peter.komadel@savba.sk.
authors.forename: Peter
authors.initials: P
authors.lastname: Komadel
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000327:Adsorption; D001546:Bentonite / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D019265:Spectroscopy, Near-Infrared / Q000379:methods
chemical_list: D000097:Acetonitriles; D001546:Bentonite; D003300:Copper; D004121:Dimethyl Sulfoxide; C032159:acetonitrile
keywords: Acetonitrile; Adsorption; Copper fixation; Dimethylsulfoxide; Montmorillonite; Near infrared spectroscopy