title: Near infrared spectroscopy of stearic acid adsorbed on montmorillonite.
abstract: The adsorption of stearic acid on both sodium montmorillonites and calcium montmorillonites has been studied by near infrared spectroscopy complimented with infrared spectroscopy. Upon adsorption of stearic acid on Ca-Mt additional near infrared bands are observed at 8236 cm(-1) and is assigned to an interaction of stearic acid with the water of hydration. Upon adsorption of the stearic acid on Na-Mt, the NIR bands are now observed at 5671, 5778, 5848 and 5912 cm(-1) and are assigned to the overtone and combination bands of the CH fundamentals. Additional bands at 4177, 4250, 4324, 4337, 4689 and 4809 cm(-1) are attributed to CH combination bands resulting from the adsorption of the stearic acid. Stearic acid is used as a model molecule for adsorption studies. The application of near infrared spectroscopy to the study of this adsorption proved most useful.
authors.affiliation: School of Physical and Chemical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
authors.forename: Longfei
authors.initials: L
authors.lastname: Lu
authors.forename: Jingong
authors.initials: J
authors.lastname: Cai
authors.forename: Ray L
authors.initials: RL
authors.lastname: Frost
mesh_terms: D000327:Adsorption; D001546:Bentonite / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry; D012964:Sodium / Q000737:chemistry; D013055:Spectrophotometry, Infrared / Q000379:methods; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013229:Stearic Acids / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D013229:Stearic Acids; D014867:Water; D001546:Bentonite; C031183:stearic acid; D012964:Sodium; D002118:Calcium