Preparation and use of a mesoporous silicate material for the removal of tetramethyl ammonium hydroxide (TMAH) from aqueous solution

Abstract

A cubic mesoporous silicate (CMS) was prepared, characterised, and assessed as an adsorbent for tetramethyl ammonium hydroxide (TMAH) from aqueous solution. The adsorption process was studied as a function of temperature and time. Sorption closely followed the Langmuir model. The adsorption of TMAH on CMS was endothermic and kinetic studies suggest that the overall rate of adsorption was pseudo-second-order. Pore diffusion effects contribute to limiting the overall rate of adsorption while at lower initial TMAH concentrations, ®lm diffusion becomes more important. Desorption studies were carried out using water and methanol. Methanol was the superior desorbing agent.

Efficient adsorptive removal of Tetramethylammonium hydroxide (TMAH) from water using graphene oxide

“…In a previous study, Kelleher et al had demonstrated using the mesoporous silicates to adsorb TMAH with C 0 = 50-800 mg/L at 23°C, and obtained the adsorption capacity of $ 100 mg/g with C 0 = 200 mg/L [8]. With the same C 0 and similar experimental conditions, GO exhibited a comparable adsorption capacity for TMAH as the mesoporous silicates but the regeneration efficiency of GO could reach 94%, which was much higher that regeneration efficiency (40%) of the mesoporous silicate material [8].…”

“…A few studies had indicated that the adsorption process is a feasible technique to remove TMAH from water [8,9] using a mesoporous silicate and commercial activated carbons as adsorbents. However, the adsorbents were not particularly functionalized with task-specific functional groups (e.g., acidic sites) to enhance the adsorption of highly basic TMAH.…”

Adsorption of phenol and o-chlorophenol by mesoporous MCM-41

“…It was believed that micropores provide adsorptive sites in aqueous solution, but it was found that the total surface area of micropores cannot be totally utilized in adsorption. The extent to which particular adsorbate molecule adsorbs on these zeolite materials is limited by a number of physical factors which includes the size of the adsorbing molecules, the pore diameter of the specific zeolite and the length of the diffusion path [22].…”

A novel process for the removal of aniline from wastewaters

“…Regeneration of the spent adsorbent material can be a costly and intensive process [18]. This has lead to an interest in developing alternative adsorbents for the removal of organic pollutants from aqueous waste streams [19,20].…”