Infrared spectroscopy borosilicate

Sealed borosilicate glass ampoules (ca. 135 ml.), equipped with one or more break seals, were used for all hydrolytic reactions. In the experiments involving NF3 and caustic soda, the base was contained in loose-fitting Teflon cups within the ampoules to prevent attack on the glass. Infrared spectroscopy was generally used for the analysis of gaseous products. 

The solid product of the reaction was identified by infrared spectroscopy (IR). The reaction was carried out in a borosilicate glass cell 6 cm long and 2.1 cm in diameter with NaCl windows but using higher... 

Infrared Spectroscopy. Infrared spectroscopy has been used to study borosilicate molecular sieves (22.25.33-361. Vibrational bands associated with trigonal framework boron occur near 900 cm"1 and 1400 cm 1 (22.25.331. The presence of the Si-0-B asymmetric stretching vibration, indicative of tetrahedral framework boron incorporation, cannot be observed directly because it is masked by the strong Si-0-Si band near 1100 cm-1 in the pentasil structures. The tetrahedral Si-O-B vibration has been observed for the borosilicate mineral danburite (.33). Shifts of bands in the framework vibrational region at 550 cm"1 and 560 cm"1 to higher frequencies as a function of boron content has been used to study boron incorporation in the framework of AMS-1B borosilicate (36). 

Crystalline borosilicate molecular sieves have been the object of an intensive investigation effort since they were reported in the open literature at the Fifth International Conference on Zeolites by Taramasso, et al. (1) A wide range of structures containing framework boron have been synthesized. The physical properties of these borosilicate molecular sieves have been studied by such techniques as X-ray diffraction, infrared and nuclear magnetic resonance spectroscopies, and temperature programmed desorption of ammonia. In addition, the catalytic performance of borosilicate molecular sieves has been reported for such reactions as xylene isomerization, benzene alkylation, butane dehydroisomerization, and methanol conversion. This paper will review currently available information about the synthesis, characterization, and catalytic performance of borosilicate molecular sieves. 

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