Nuclear chemistry

Catalysis

Adsorption

Engineering

Nanoparticle

Mesoporous material

Thermogravimetric analysis

Materials science

Chemical engineering

BET theory

Langmuir adsorption model

Nanotechnology

Organic chemistry

Aqueous solution

Mesoporous silica

Surface modification

Composite material

Chemistry

Fourier transform infrared spectroscopy

Triethoxysilane

Specific surface area

Current Research in Green and Sustainable Chemistry

Mesoporous silica nanoparticles (MSN) were synthesized using rice husk (RH) as the raw material via sol-gel pathway using cetyltrimethylammonium bromide (CTAB) as the structure directing agent. Silica nanoparticles were successfully functionalized with 3-aminopropyl triethoxysilane (APTES) via in-situ and post functionalization methods. Synthesized nanoparticles were characterized by X-Ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) surface area analysis. The amorphous silica nanoparticles were of 50–60 ​nm in diameter with a surface area of 150 ​m2/g, pore volume of 0.237 ​cm3/g and average pore size of 3.62 ​nm. Morphology and textural parameters were changed upon functionalization. The equilibrium adsorption capacity of MSN-A (4.94 ​mg/g) to adsorb 10 ​mg/L methylene blue (MB), was higher than in amine functionalized silica nanoparticles. The influence of experimental factors such as pH, adsorbent dosage, and initial MB concentration on adsorption of MB to MSN-A were studied. The equilibrium data for MB adsorption on mesoporous silica nanoparticles well fitted to Langmuir equation, with a maximum monolayer capacity of 19.26 ​mg/g. The adsorption of MB could be best described by the pseudo-second order model. The results indicate that MSN-A is a potential mesoporous material fabricated by cheap natural resources to remove MB from aqueous solutions.

Synthesis of mesoporous silica nanoparticles derived from rice husk and surface-controlled amine functionalization for efficient adsorption of methylene blue from aqueous solution