Yamazaki, T., Watanuki, I., Ozawa, S. and Ogino, Y. (1988) Infrared Spectra of Methane Adsorbed by Ion-Exchanged ZSM-5 Zeolites. Langmuir, 4, 433-438.
https://doi.org/10.1021/la00080a031

has been cited by the following article:

• TITLE: Alkali Treatment of Commercial Silicoaluminophosphate Molecular Sieves (SAPO-34) Enhances the Water Adsorption and Desorption Properties

  AUTHORS: Masahiro Katoh, Kota Horiuchi, Ayaka Satoh, Kota Aoyagi, Shigeru Sugiyama

  KEYWORDS: Alkali Treatment, Silicoaluminophosphate Molecular Sieves, Water, Adsorption, Desorption

  JOURNAL NAME: Journal of Encapsulation and Adsorption Sciences, Vol.9 No.4, December 6, 2019

  ABSTRACT: Commercial silicoaluminophosphate molecular sieves (SAPO-34) received alkali treatment with either NaOH (0.2, 0.01, 0.005, or 0.001 M) or NH4OH (0.005 M). Treatment with NaOH (0.005 M) increased the water adsorption initial rate of SAPO-34 by 1.4-fold. The alkali treatment introduced Na+ adsorption sites into the SAPO-34. The desorption ratio (adsorption at 30°C and desorption at 100°C) was 88.2% higher than the original rate (84.3%). On the other hand, after alkali treatment of SAPO-34 using NH4OH (0.005 M), calcination resulted in the highest desorption ratio at 91.3%. When combined with calcination, alkali treatment with NH4OH introduced H+adsorption sites into SAPO-34, H+ adsorption sites feature low levels of interaction with water, which enhanced the desorption ratio, but decreased the initial adsorption rate. These results indicate that treating commercial SAPO-34 with 0.005 M NaOH enhances both the adsorption and desorption behaviors.