%0 Journal Article
%T Alkali Treatment of Commercial Silicoaluminophosphate Molecular Sieves (SAPO<sub>-</sub>34) Enhances the Water Adsorption  and Desorption Properties
%A Masahiro Katoh
%A Kota Horiuchi
%A Ayaka Satoh
%A Kota Aoyagi
%A Shigeru Sugiyama
%J Journal of Encapsulation and Adsorption Sciences
%P 149-158
%@ 2161-4873
%D 2019
%I Scientific Research Publishing
%R 10.4236/jeas.2019.94008
%X Commercial silicoaluminophosphate molecular sieves (<span style=\"white-space:nowrap;\">SAPO-34</span>) received alkali treatment with either NaOH (0.2, 0.01, 0.005, or 0.001 M) or NH<sub>4</sub>OH (0.005 M). Treatment with NaOH (0.005 M) increased the water adsorption initial rate of <span style=\"white-space:nowrap;\">SAPO-34</span> by 1.4-fold. The alkali treatment introduced Na<sup>+</sup> adsorption sites into the <span style=\"white-space:nowrap;\">SAPO-34</span>. The desorption ratio (adsorption at 30<span style=\"white-space:nowrap;\">ˇăC</span> and desorption at 100<span style=\"white-space:nowrap;\">ˇăC</span>) was 88.2% higher than the original rate (84.3%). On the other hand, after alkali treatment of <span style=\"white-space:nowrap;\">SAPO-34</span> using NH<sub>4</sub>OH (0.005 M), calcination resulted in the highest desorption ratio at 91.3%. When combined with calcination, alkali treatment with NH<sub>4</sub>OH introduced H<sup>+</sup>adsorption sites into <span style=\"white-space:nowrap;\">SAPO-34</span>, H<sup>+</sup> 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 <span style=\"white-space:nowrap;\"><span style=\"white-space:nowrap;\">SAPO-34</span></span> with 0.005 M NaOH enhances both the adsorption and desorption behaviors.
%K Alkali Treatment
%K Silicoaluminophosphate Molecular Sieves
%K Water
%K Adsorption
%K Desorption
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=96914