Nanoparticles of Ca oxide were prepared via hydrothermal method and Na dodecyl sulphate was used as templating agent. The as-synthesized NP-CaO was used as precursor of aluminum doped Ca oxide nanoparticles. Both type of compounds were used to destructively adsorb 2,4,6 trinitrophenol. The setup, chemicals and instruments used for the experimental work are following:
Apparatus and Chemicals:
The chemicals and setup used during experimental work is listed as followers:
Analytic balance AY220 ( Shimadzu ) Maximum 220g. 0.001mg truth
UV-VIS spectrophotometer UV-1700, Shimadzu
HPLC, LC 20T with Diode Array Detector ; Shimadzu
GCMS QP-2010, Shimadzu
FTIR MIDAC M 2000
TGA SDT Q600 V8.3 Build 101
Scan velocity mini ( Labogene ) soap. velocity: 13500 revolutions per minute
Beakers 250ml, 100ml, 50ml
Measuring Flasks 250ml, 100ml, 50ml
All chemicals used in experimental work were of analytical class.
2,4,6 Trinitrophenol ( Picric Acid ) moistened with H2O ?98 % Sigma Aldrich
Calcium Chloride anhydrous, Merck
Sodium Hydroxide, Merck
Sodium Dodecyl Sulfate, Merck
Aluminium Chloride, Riedel-de Ha & A ; euml ; n
Methanol, Riedel-de Ha & A ; euml ; n
Preparation Method for Solutions:
Following are the methods of readying of all solutions used during experimental work. All solutions were prepared in distilled H2O to avoid any taint or dross.
0.15M CaCl2 Solution
0.30M NaOH Solution
15mM AlCl3.6H2O Solution
Sodium Dodecyl Sulfate Solutions of different Concentrations: 0.004M, 0.006M, 0.008M, 0.01M and 0.012M
Synthesis of CaO Nanoparticles by Hydrothermal Method:
Calcium oxide nanoparticles were prepared by altering reaction parametric quantity i.e. temperature and concentration of wetting agent to analyze their consequence on atom size and catalytic activity.
The mixture incorporating 0.15M of CaCl2 and 0.008M SDS ( anionic wetting agent ) was magnetically stirred at ambient temperature. The precursor to surfactant molar ratio was 1M:0.05M. 0.30M sodium hydrated oxide as precipitating agent was added bead wise and the reaction solution was allowed to stir for 30 proceedingss. After stirring, the Teflon line drive of chromium steel steel autoclave ( hydrothermal bomb ) was fraught with reaction suspension and maintain in oven for 4 hours at coveted temperature ( 250 oC, 200 oC 180 oC, 160 oC, 140 oC ) .
Same as above process was adopted to analyze the consequence of wetting agent, merely molar concentration of SDS was varied near and far from its cmc ( crticle micelle concentration ) value ( 0.004M, 0.006M, 0.008M, 0.01M and 0.012M ) .
CaCl2 + 2NaOH Ca ( OH ) 2 + 2NaCl
Ca ( OH ) 2 CaO
After 4hrs, the sterilizer was taken out from oven and allowed to chill for 2 hours at ambient temperature. The precipitates of Ca ( OH ) 2 were separated ; washed 3 times with methyl alcohol and 2 times with deionised H2O to take any reactant, ions or wetting agent and neutralize their pH by utilizing centrifugation machine at 13000rpm velocity. The precipitates were dried and calcined at 600 oC in a furnace with air flow for 3 hours [ 43 ] .
Preparation of Al Doped Calcium Oxide Nanoparticles Hydrothermal Method:
For synthesis of aluminum doped Ca oxide nanoparticles, deposition-precipitation method [ 55 ] was adopted. AlCl3.6H2O and as-synthesised CaO nanoparticles were used as precursors. 15mM solution of AlCl3.6H2O was prepared in 9ml of deionized H2O and 50 milligram of NP-CaO was added in different clip intervals to achieve pH 12.3 for point of zero charge [ 56 ] . Meanwhile the reaction was invariably on magnetic stirring. Teflon line drive of sterilizer ( unstained steel ) was fraught with reaction solution and kept in oven for 4 hour at temperature same as that of NP-CaO precursor. The precipitates were washed and calcined same as ascribed above.
Table: 2 Nanoparticle of Calcium oxide prepared by altering hydrothermal temperature and maintaining other parametric quantities changeless [ 0.008M SDS ( Surfactant ) , Calcination Conditions ( 600 & A ; deg ; C and 3h ) , Hydrothermal Reaction Time 4h ] .
Hydrothermal Reaction Temperature ( & A ; deg ; C )
Table: 3 Synthesis of CaO nanoparticles by altering surfactant concentration and maintaining other parametric quantities same [ Hydrothermal Conditions ( 180 & A ; deg ; C and 4h ) , Calcination Conditions ( 600 & A ; deg ; C and 3h ) ]
Surfactant Conentration ( M )
Table: 4 Preaparation of Al/CaO nanoparticles by utilizing CaO precursor of variant Surfactant concentration. [ Hydrothermal Conditions ( 180 & A ; deg ; C and 4h ) , Calcination Conditions ( 600 & A ; deg ; C and 3h ) ]
Surfactant Conentration ( M )
Method of Characterization:
Chemicals and Solutions:
15ppm solution of 2,4,6-Trinitrophenol ( Picric acid )
5mg CaO nanoparticles
5 milligram Al/CaO nanoparticles
Methanol [ pH=3.4 ]
Measurement of Catalytic Activity by UV-VIS Spectrophotometer:
The catalytic activity of samples synthesised by hydrothermal method by altering different parametric quantities [ Table 2, 3, 4 ] was determined. For this intent, 15 ppm solution of 2,4,6 Trinitrophenol was prepared in 100ml of distilled H2O and 5 milligram of the nanocatalyst was added to 25 milliliter of this solution. The spectra of 2,4,6 Trinitrophenol solution was obtained before and after add-on of accelerator. The solution with nano-catalyst was placed under UV irradiation with changeless magnetic stirring for 15 proceedingss at ambient temperature. The optical density of the sample was taken at ?max 356 nanometer after every 1 min interval.
High Performance Liquid Chromatography:
The picric acid was besides analysed by DAD HPLC by utilizing C18 column. A 15ppm solution of picric acid was prepared in dual distilled H2O ; there were three types of solutions used.
15ppm solution of standard picric acid
15ppm solution of picric acid with CaO accelerator
15ppm solution of picric acid with Al/CaO accelerator
70 % methyl alcohol [ pH: 3.4 ] was used as nomadic stage for all these solutions. The injection volume of standard picric acid was 20 µL. After 7.5 proceedingss of injection, a really crisp extremum of 7.425 was observed at 355nm. The 2nd solution was prepared by adding CaO nanocatalyst. It was invariably stirred under UV lamp irradiation for 15 min. Then it was filtered and an injection volume of 20 µL was injected in HPLC. Same process was repeated for 3rd solution except, alteration of nanocatalyst.