Open AccessAn Investigation into the Adsorption Characteristics of Grafted Mesoporous Silicates for the Removal of Tetramethyl Ammonium Hydroxide from Aqueous Solution
Author(s) -
Brian P. Kelleher,
Aidan M. Doyle,
B.K. Hodnett,
Thomas F. O’Dwyer
Publication year - 2002
Publication title -
adsorption science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.682
H-Index - 36
eISSN - 2048-4038
pISSN - 0263-6174
DOI - 10.1260/026361702321104273
Subject(s) - adsorption , chemistry , aqueous solution , sorption , ammonium hydroxide , mesoporous material , langmuir , amine gas treating , inorganic chemistry , monolayer , freundlich equation , hydroxide , langmuir adsorption model , ammonium , chemical engineering , organic chemistry , biochemistry , engineering , catalysis
Four cubic mesoporous silicates (CMS), one unmodified and three grafted with amine, carboxylic and cyano surface functional groups, were prepared, characterised and compared as adsorbents for tetramethyl ammonium hydroxide (TMAH) from aqueous solution. The adsorption process was studied as a function of molecular size and CMS pore volume. Sorption on the unmodified, cyano- and carboxylic-grafted adsorbents closely followed the Langmuir model while adsorption on the amine-treated silicate conformed to the Freundlich model. A comparison of the adsorbent pore volume and the volume of sorbed TMAH molecules suggested that monolayer sorption occurred, there being some evidence that surface functional groups influenced the adsorption process. The presence or absence of structural order, as defined by X-ray diffraction analysis, had no significant influence on the adsorption, as all materials, both ordered and disordered, had relatively high adsorption capacities.