Anal. Method Environ. Chem. J. 4 (1) (2021) 46-57
2.2. Synthesis of UVM-7
spectrophotometer at 502 and 664 nm for Dr and
MB, respectively. In binary solution, the best
wavelength for each dye was ﬁnd out utilizing ﬁrst-
order derivative spectrometry.
in which triethanol amine (TEAH3), has effect on
the rate of hydrolysis and condensation of teraethyl
orthosilicate (TEOS). In a typical synthesis, mixture
of TEOS and TEAH3 heated up to 120 °C and then
CTAB (cetyltrimethylammonium bromide) was
added when the temperature of the solution reached
to 70°C. After addition of water a suspension was
formed and aged for 4 hours at ambient temperature.
The ﬁnal molar composition of the synthesis mixture
was 1.0 TEOS : 3.5 TEAH3 : 0.25 CTAB : 90 H2O.
The product was ﬁltered, washed with water and
acetone and dried in an oven at 80°C overnight and
calcined at 550°C for 6 hours.
The adsorption percentage (R%) and adsorption
capacity of each dye qe, (mg dye/g adsorbent) was
calculated according to the following equations
(Eq.1 and Eq.2):
2.3. Synthesis of NH2- /UVM-7/SO3H
First, 1.0 g of aminopropyle triethoxysilane
(APTES) was added to the aqueous solution of
CTAB and after 5 minutes, mixture of TEOS and
TEAOH, was added to the micellar solution. The
reactants molar ratio was 1.0 TEOS: 3.5 TEAH3
: 0.25 CTAB : 90 H2O: 0.20 APTES. After aging,
the white suspension was ﬁltered and washed
thoroughly with water and acetone. The white
precipitate dried in oven over night at 80 °C. At the
second step, 1.0 g of the as-synthesized NH2/UVM-
7 and 1.0 g of triethoxysilane propanethiol (TPTES)
was reﬂuxed in 50 mL of toluene for 12 hours and
then, the mixture ﬁltered and dried in oven again.
Then, thiol groups grafted on the external surface
of the sample was oxidized in 15% H2O2 and 1
molar solution of H2SO4. Then, CTAB of the as-
synthesized NH2/UVM-7/SO3H was removed by
reﬂux in 1 molar ethanolic solution of HCL for 24
hours to get access to the internal pores and amine
groups. The ﬁnal product was dried in oven at 80
°C in vacuum oven overnight.
Where C0 and Ce (mg L-1) are the initial and
equilibrium concentration of dye, respectively. V
(L) is the volume of the solution and M (g) is the
mass of adsorbent used.
X-ray diffraction (XRD) patterns were recorded
using a Philips 1840 diffractometer using nickel-
ﬁltered Cu Kα (1.5418˚ A) X-ray source, operating
at 35.4 kV and 28 mA. Textural properties of the
synthesized samples were measured by nitrogen
adsorption at 77 K using a BELSORP-max
apparatus after being out-gassed in vacuum at 120
Elementar. FT-IR spectra was recorded using a FT-
IR 70 VERTX Bruker spectrophotometer using
KBr powder. UV–Vis spectrophotometer was used
to measure the concentration of the Methylene
Blue and Direct red23 in aqueous solution. FE-
SEM images were captured using Mira TESCAN
3-XMU. Samples were sputtered with gold prior
to imaging. TEM images were recorded at 150 kV
operating voltage using a Zeiss microscope.
2.4. Batch adsorption procedure
In each test, 0.1 g of adsorbent was added to the 10
mL of a solution containing a known concentration
of each dyes while agitating at 250 rpm at 25 °C.
After 120 minutes the concentration of residual
dyes in supernatant was determined by UV–Vis
3. Results and discussion
3.1. Characterization of NH2/UVM-7/SO3H
XRD pattern of NH2/UVM-7/SO3H is shown in Figure 2.