2.2. Instrumentation
The residual concentration of metal ion in the filtrate were analyzed by GBC, Sensaa Series Atomic Absorption Spectrometry (computerized AAS) with air-acetylene flame under the optimum instrumental conditions as shown in (Table 1). The solution pH was measured using digital pH meter (Hanna instrument model HI 8519, Italy). Fourier transform infrared (FT-IR) spectra were measured on Nicolet is 10 FTIR spectrometer in the range of (4000 to 400 cm-1). Scanning electron microscope (SEM, Quanta 250 FEG, FEI Company, USA) at an accelerating voltage of 30 kV was used for evaluation of surface morphology and particle size determination. The specific surface area of the HAPNRs was measured by the BET-method (adsorption gas N2, carrier …show more content…
Synthesis of Nano-silica-Cl
Nano-SiO2-functionalized-Cl was synthesized via surface reaction of Nano-SiO2 by using 3-chloroproyltrimethoxysilane as the silylation agent. 2.0 g of Nano-SiO2 and 50 ml of toluene were mixed into a 250 mL round flask. 4.0 mL of 3-chloropropyltrimethoxysilane was then added and the mixture was refluxed at 110°C with continuous stirring for 6 hours. The resulting functionalized Nano-SiO2-Cl was collected and washed by ethanol and diethylether several times and dried at 50°C until complete dryness.
2.3.3. Synthesis of Nano-silica-folic acid (NS-FA)
Folic acid was used to functionalize Nano-SiO2-Cl for the formation of Nano-SiO2-folic acid according to the following procedure. 2.0 g of Nano-SiO2-Cl was added to 50 ml of toluene in a 250 mL round flask. 2.0 g of folic acid was then added and the mixture was refluxed at 110°C and continuous stirring for 6 hours, filtered and washed by ethanol and diethylether several times and dried at 50°C to complete dryness.
2.4. Metal ion uptake experiments using batch method
2.4.1. Solid-phase …show more content…
It's visible that, after the chlorination step and modification of silica, the content of nitrogen show visibly increases. From the obtained results the insertion of the folic acid moieties onto the chlorinated modified silica is shown.
3.1.2. Infrared spectra (FT-IR)
FTIR was used to ascertain the immobilized folic acid onto the surface of the nano-silica. The FTIR spectra of the nano-silica is shown in (Fig. 1). The sharp feature around 1100 cm-1 indicating Si-O-Si stretching vibration. The presence of adsorption water was reflected by the presence of OH vibration at 3440 cm-1 and 1632 cm-1. For chlorinated nano-silica, the presence of chlorine was reflected by the presence of stretching vibration at 900 cm-1 and after addition of folic acid the presence of new peaks at 1750 cm-1 was reflected the presence of new carbonyl group of carboxylic group.
3.1.3. Scan electron microscope (SEM)
The morphology and size of the raw and modified silica were studied by SEM. (Fig. 2) a shows SEM of the nano-silica, it can be concluded that the modified silica is comprised of aggregated nanoparticles with average size less than 100
The residual concentration of metal ion in the filtrate were analyzed by GBC, Sensaa Series Atomic Absorption Spectrometry (computerized AAS) with air-acetylene flame under the optimum instrumental conditions as shown in (Table 1). The solution pH was measured using digital pH meter (Hanna instrument model HI 8519, Italy). Fourier transform infrared (FT-IR) spectra were measured on Nicolet is 10 FTIR spectrometer in the range of (4000 to 400 cm-1). Scanning electron microscope (SEM, Quanta 250 FEG, FEI Company, USA) at an accelerating voltage of 30 kV was used for evaluation of surface morphology and particle size determination. The specific surface area of the HAPNRs was measured by the BET-method (adsorption gas N2, carrier …show more content…
Synthesis of Nano-silica-Cl
Nano-SiO2-functionalized-Cl was synthesized via surface reaction of Nano-SiO2 by using 3-chloroproyltrimethoxysilane as the silylation agent. 2.0 g of Nano-SiO2 and 50 ml of toluene were mixed into a 250 mL round flask. 4.0 mL of 3-chloropropyltrimethoxysilane was then added and the mixture was refluxed at 110°C with continuous stirring for 6 hours. The resulting functionalized Nano-SiO2-Cl was collected and washed by ethanol and diethylether several times and dried at 50°C until complete dryness.
2.3.3. Synthesis of Nano-silica-folic acid (NS-FA)
Folic acid was used to functionalize Nano-SiO2-Cl for the formation of Nano-SiO2-folic acid according to the following procedure. 2.0 g of Nano-SiO2-Cl was added to 50 ml of toluene in a 250 mL round flask. 2.0 g of folic acid was then added and the mixture was refluxed at 110°C and continuous stirring for 6 hours, filtered and washed by ethanol and diethylether several times and dried at 50°C to complete dryness.
2.4. Metal ion uptake experiments using batch method
2.4.1. Solid-phase …show more content…
It's visible that, after the chlorination step and modification of silica, the content of nitrogen show visibly increases. From the obtained results the insertion of the folic acid moieties onto the chlorinated modified silica is shown.
3.1.2. Infrared spectra (FT-IR)
FTIR was used to ascertain the immobilized folic acid onto the surface of the nano-silica. The FTIR spectra of the nano-silica is shown in (Fig. 1). The sharp feature around 1100 cm-1 indicating Si-O-Si stretching vibration. The presence of adsorption water was reflected by the presence of OH vibration at 3440 cm-1 and 1632 cm-1. For chlorinated nano-silica, the presence of chlorine was reflected by the presence of stretching vibration at 900 cm-1 and after addition of folic acid the presence of new peaks at 1750 cm-1 was reflected the presence of new carbonyl group of carboxylic group.
3.1.3. Scan electron microscope (SEM)
The morphology and size of the raw and modified silica were studied by SEM. (Fig. 2) a shows SEM of the nano-silica, it can be concluded that the modified silica is comprised of aggregated nanoparticles with average size less than 100