Acid Treatments of Naturally Occurring Microporous Particles for the Purpose of Water Filtration
Mentor 1
Marcia R. Silva
Location
Union Wisconsin Room
Start Date
28-4-2017 1:30 PM
End Date
28-4-2017 4:00 PM
Description
Naturally occurring porous particles are some of the oldest mediums for water filtration. Most of these are carbon, polysaccharide, silica or alumina based. The molecular framework of the natural porous particles used here primarily consists of tetrahedral aluminasilicate bonds. This unique Si/Al framework makes them good choices as adsorbents, especially for heavy metals and wastewater treatment. Recent developments in this field have shed light on the potential of these materials to be chemically modified in order to further aid in freshwater filtration. Among these methods, acid treatment seems to be one of the most common and simple treatments that can be applied. The aim of the acid treatments is to de-aluminate the porous particles, removing alumina bonds from the cage structure. To accomplish this, various acids can be utilized to achieve the adsorption increasing results of acid treatment, including: H2SO4, HCl, HNO3, and acetic acid. The material goes through a cleaning process of sonication and microwaving, and then treated with the aforementioned acids. This study focuses on comparing the effectiveness of these acids in increasing the overall Si/Al ratio among the molecular framework of the porous material, in turn making the particles more mesoporous and increasing adsorption surface area. The porous particles were analyzed in their raw state, after the cleaning process, and after each type of acid treatment. Materials were characterized by gas sorption analysis, Fourier transform infrared (FTIR) spectroscopy, XRD analysis. The results show that acid treatments are effective in increasing overall adsorption surface area and meso/microporosity.
Acid Treatments of Naturally Occurring Microporous Particles for the Purpose of Water Filtration
Union Wisconsin Room
Naturally occurring porous particles are some of the oldest mediums for water filtration. Most of these are carbon, polysaccharide, silica or alumina based. The molecular framework of the natural porous particles used here primarily consists of tetrahedral aluminasilicate bonds. This unique Si/Al framework makes them good choices as adsorbents, especially for heavy metals and wastewater treatment. Recent developments in this field have shed light on the potential of these materials to be chemically modified in order to further aid in freshwater filtration. Among these methods, acid treatment seems to be one of the most common and simple treatments that can be applied. The aim of the acid treatments is to de-aluminate the porous particles, removing alumina bonds from the cage structure. To accomplish this, various acids can be utilized to achieve the adsorption increasing results of acid treatment, including: H2SO4, HCl, HNO3, and acetic acid. The material goes through a cleaning process of sonication and microwaving, and then treated with the aforementioned acids. This study focuses on comparing the effectiveness of these acids in increasing the overall Si/Al ratio among the molecular framework of the porous material, in turn making the particles more mesoporous and increasing adsorption surface area. The porous particles were analyzed in their raw state, after the cleaning process, and after each type of acid treatment. Materials were characterized by gas sorption analysis, Fourier transform infrared (FTIR) spectroscopy, XRD analysis. The results show that acid treatments are effective in increasing overall adsorption surface area and meso/microporosity.
