נגישות
menu      
חיפוש מתקדם
Lapides, I., Institute of Chemistry, Hebrew University of Jerusalem, Campus Edmund Y. Safra, Jerusalem 91904, Israel
Borisover, M., Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, POB 6, Bet Dagan 50250, Israel
Yariv, S., Institute of Chemistry, Hebrew University of Jerusalem, Campus Edmund Y. Safra, Jerusalem 91904, Israel
Na-montmorillonite (Na-MONT) was loaded with hexadecyltrimethylammonium cations (HDTMA) by replacing 41 and 90% of the exchangeable Na with HDTMA, labeled OC-41 and OC-90, respectively. Na-MONT, OC-41, and OC-90 were heated in air up to 900 °C. Unheated and thermally treated organoclays heated at 150, 250, 360, and 420 °C are used in our laboratory as sorbents of different hazardous organic compounds from waste water. In order to get a better knowledge about the composition and nature of the thermally treated organoclays Na-MONT and the two organo-clays were studied by thermogravimetry (TG) in air and under nitrogen. Carbon and hydrogen contents in each of the thermal treated sample were determined and their infrared spectra were recorded. The present results showed that at 150 °C both organoclays lost water but not intercalated HDTMA cations. At 250 °C, many HDTMA cations persisted in OC-41, but in OC-90 significant part of the cations were air-oxidized into H2O and CO2 and the residual carbon formed charcoal. After heating both samples at 360 °C charcoal was present in both organo clays. This charcoal persisted at 420 °C but was gradually oxidized by air with further rise in temperature. TG runs under nitrogen showed stepwise degradation corresponding to interlayer water desorption followed by decomposition of the organic compound, volatilization of small fragments and condensation of non-volatile fragments into quasi-charcoal. After dehydroxylation of the clay the last stages of organic matter pyrolysis and volatilization occurred. © 2011 Akadémiai Kiadó, Budapest, Hungary.
פותח על ידי קלירמאש פתרונות בע"מ -
הספר "אוצר וולקני"
אודות
תנאי שימוש
Thermal analyis of hexadecyltrimethylammonium-montmorillonites: Part 1. Thermogravimetry, carbon and hydrogen analysis and thermo-IR spectroscopy analysis
105
Lapides, I., Institute of Chemistry, Hebrew University of Jerusalem, Campus Edmund Y. Safra, Jerusalem 91904, Israel
Borisover, M., Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, POB 6, Bet Dagan 50250, Israel
Yariv, S., Institute of Chemistry, Hebrew University of Jerusalem, Campus Edmund Y. Safra, Jerusalem 91904, Israel
Thermal analyis of hexadecyltrimethylammonium-montmorillonites: Part 1. Thermogravimetry, carbon and hydrogen analysis and thermo-IR spectroscopy analysis
Na-montmorillonite (Na-MONT) was loaded with hexadecyltrimethylammonium cations (HDTMA) by replacing 41 and 90% of the exchangeable Na with HDTMA, labeled OC-41 and OC-90, respectively. Na-MONT, OC-41, and OC-90 were heated in air up to 900 °C. Unheated and thermally treated organoclays heated at 150, 250, 360, and 420 °C are used in our laboratory as sorbents of different hazardous organic compounds from waste water. In order to get a better knowledge about the composition and nature of the thermally treated organoclays Na-MONT and the two organo-clays were studied by thermogravimetry (TG) in air and under nitrogen. Carbon and hydrogen contents in each of the thermal treated sample were determined and their infrared spectra were recorded. The present results showed that at 150 °C both organoclays lost water but not intercalated HDTMA cations. At 250 °C, many HDTMA cations persisted in OC-41, but in OC-90 significant part of the cations were air-oxidized into H2O and CO2 and the residual carbon formed charcoal. After heating both samples at 360 °C charcoal was present in both organo clays. This charcoal persisted at 420 °C but was gradually oxidized by air with further rise in temperature. TG runs under nitrogen showed stepwise degradation corresponding to interlayer water desorption followed by decomposition of the organic compound, volatilization of small fragments and condensation of non-volatile fragments into quasi-charcoal. After dehydroxylation of the clay the last stages of organic matter pyrolysis and volatilization occurred. © 2011 Akadémiai Kiadó, Budapest, Hungary.
Scientific Publication
You may also be interested in