Nanoporous silica polyamine composites for metal ion capture from rice hull ash

2011 ◽  
Vol 25 (7) ◽  
pp. 530-536 ◽  
Author(s):  
Matt Berlin ◽  
Jesse Allen ◽  
Varadharajan Kailasam ◽  
David Rosenberg ◽  
Edward Rosenberg
2010 ◽  
Vol 12 (2) ◽  
pp. 123
Author(s):  
Matt Berlin ◽  
Jesse Allen ◽  
Varadharajan Kailasam ◽  
David Rosenberg ◽  
Edward Rosenberg

Rice Hull Ash (RHA) was converted to amorphous silica gel using a modified version of published literature procedures. The gels were characterized by a comparison of their CPMAS [29] Si NMR and Scanning Electron Microscopy (SEM) images with commercial silica gels. The resulting gels were silanized with a 7.5:1 mixture of methyltrichlorosilane and chloropropyltrichlorosilane and then reacted with poly(allylamine) (PAA) to produce the silica polyamine composite (SPC) BP-1. The BP-1 was then further modified with pyridine-2-carboxaldehyde to form the copper selective SPC, CuSELECT. This procedure follows that used to produce the commercialized version of these composite materials from commercially available amorphous silica gels. The composites were characterized by solid state NMR techniques, elemental analysis, SEM, porosimetry, and metal ion capacity and selectivity. The overall goal of the project was to determine the feasibility of using RHA to make SPC. The observed strengths and weaknesses of this approach are discussed.


2018 ◽  
Vol 16 (1) ◽  
pp. 45 ◽  
Author(s):  
F. Widhi Mahatmanti ◽  
Nuryono Nuryono ◽  
Narsito Narsito

In this research, chitosan based membrane blended with rice hull ash (RHA) silica and polyethylene glycol (PEG) has been applied as adsorbent of Ca(II), Mg(II), Zn(II) and Cd(II) in an aqueous solution. Membrane was synthesized by blending RHA silica and polyethylene glycol into chitosan. Silica and polyethylene glycol blended into the chitosan to improve the mechanical properties and the membrane porous. The membrane was characterized using Fourier Transform infrared (FTIR) spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and swelling degree analyzer. Adsorption of metal ions investigated was conducted in a batch system with variation of pH, initial ion concentration and contact time. Thermodynamics and kinetics of adsorption were evaluated based on the adsorption data at initial metal ion concentration and contact time variations, respectively. Results showed that the optimum condition of adsorption was at pH 9.0 for Ca(II), 6.0 for both Mg(II) and Zn(II) and 5.5 for Cd(II), and contact time of 24 h for all ions investigated. Kinetics of all investigated metal ion adsorption followed a kinetic model of pseudo-second-order. Adsorption of Ca(II) and Mg(II) on the membrane fitted to Freundlich model with the affinity of 1.266 and 1.099, respectively; and Zn(II) and Cd(II) fitted to Langmuir one with the capacity of 182 and 106 µmol/g, respectively.


Waterlines ◽  
1983 ◽  
Vol 2 (2) ◽  
pp. 21-23 ◽  
Author(s):  
Barnes ◽  
Mampitiyarachichi

2016 ◽  
Vol 8 (6) ◽  
pp. 2131-2140 ◽  
Author(s):  
Ailar Hajimohammadi ◽  
Jannie S. J. van Deventer

2016 ◽  
Vol 864 ◽  
pp. 112-116
Author(s):  
Rinlee Butch M. Cervera ◽  
Emie A. Salamangkit-Mirasol

Rice hull or rice husk (RH) is an agricultural waste obtained from milling rice grains. Since RH has no commercial value and is difficult to use in agriculture, its volume is often reduced through open field burning which is an environmental hazard. In this study, amorphous nanosilica from Philippine waste RH was prepared via acid precipitation method. The synthesized samples were fully characterized for its microstructural properties. X-ray diffraction pattern reveals that the structure of the prepared sample is amorphous in nature while Fourier transform infrared spectrum showed the different vibration bands of the synthesized sample. Scanning electron microscopy (SEM) and particle size analysis (PSA) confirmed the presence of agglomerated silica particles. On the other hand, transmission electron microscopy (TEM) revealed an amorphous sample with grain sizes of about 5 to 20 nanometer range and has about 95 % purity according to EDS analyses. The elemental mapping also suggests that leaching of rice hull ash effectively removed the metallic impurity such as potassium element in the material. Hence, amorphous nanosilica was successfully prepared via a low-cost acid precipitation method from Philippine waste rice hull.


2018 ◽  
Vol 13 (2) ◽  
pp. 175-179
Author(s):  
Tossaporn Incharoen ◽  
Pichit Wonnakom ◽  
Asad Ali Khaskheli
Keyword(s):  

2005 ◽  
Vol 8 (3) ◽  
pp. 74-80
Author(s):  
Sriyanti Sriyanti ◽  
Taslimah Taslimah ◽  
Nuryono Nuryono ◽  
Narsito Narsito

Silica gel is well known as a material that may be used as adsorbent, host matrix for catalyst, etc. Hence, synthesis of silica gel from rice hull ash has been done by evaluation of the effect of medium acidity and organic group immobilized in the snythesis of silica gel.Synthesis of silica gel was done by adding sodium silicate solution from rice hull ash to hydrochloric acid until pH 3, 5 and 7. Immobilization of thiol group and amino group in silica was done by adding 3-mercaptopropyltrimethoxysilane or 3-aminopropyl-trimethoxysilane to sodium silicate solution and hydrochloride acid solution until pH: 7. The products were characterized by X-ray deffractometer and FTIR Spectroscopy.Results showed that porousitas of silica increased with increasing medium acidity ( decreasing pH medium).Immobilization thiol or amino group in silica added a functional group on silica but did not destroy primary structure of silica gel.Key Words: Silica Gel, Rice Hull Ash, 3-mercaptopropyltrimethoxysilane, 3-aminopropyl-trimethoxysilane.


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