This study highlights a pioneering approach in the development of an efficient, affordable, and economically feasible adsorbent specifically tailored for the removal of glyphosate (Gly) from ...contaminated water. To accomplish this objective, a low-cost and pure NaA Zeolite (NaAZ) was synthesized with 93% crystallinity from Austrian fly ash (AFA) as a precursor for the first-time. Taguchi design was employed to optimize critical parameters such as the SiO2/Al2O3 ratio, alkalinity concentration, time, and temperature. The cation exchange capacity (CEC) and external cation exchange capacity (ECEC) are determined as critical factors for the modification process. Subsequently, the pure NaAZ was modified with hexadecyl trimethyl ammonium chloride (HDTMAC), a cationic surfactant. The utilization of surfactant-modified zeolite (SMZ) for Gly removal demonstrates its innovative application in this field, highlighting its enhanced adsorption capacity and optimized surface properties. The AFA, NaAZ, and SMZ were characterized using analytical techniques including XRD, XRF, FTIR-ATR, SEM, TGA, BET, CHNSO analyzer and ICP-OES. The adsorbent exhibited effective Gly removal through its pH-dependent charge properties (pH 2–10), with an optimized pH 6 facilitating a significant electrostatic interaction between the adsorbent and Gly. SMZ demonstrated remarkable adsorption capacity and removal efficacy, surpassing most reported adsorbents with values of 769.23 mg/g and 98.92% respectively. Our study demonstrates the significant advantage of the SMZ, with a low leaching concentration of only 6 ppm after 60 days, ensuring environmental safety, long-term stability, and public health considerations. The kinetics of the adsorption process was well described by the pseudo-second order and the Freundlich isotherm. Pore diffusion and H-bonding were postulated to be involved in physisorption, whereas electrophilic interactions led to chemisorption type of adsorption. Consequently, SMZ provides a practical significance, broad applicability and promising solution for Gly removal, facilitating sustainable water treatment.
In the graphical abstract, we visually demonstrate the synthesis of AFA (background of backers: power plant) as an effective method for removing glyphosate from water. The mechanism of adsorption is explained in the manuscript (section 3.6). The backgrounds and ice-filled glass of water were taken from word software's online image source. ChemDraw (22, macOS, Microsoft Windows, Canada) has been used to draw the other components like the backers, the Glyphosate and surfactant structures and etc. The cubic structure of NaA zeolite was derived from the SEM findings of this investigation. Author developed the idea of graphical abstract. Display omitted
•Recycling Austrian fly ash to zeolite developed an innovative glyphosate adsorbent.•Modified zeolite removed glyphosate via a physicochemical mechanism for the first time.•The Taguchi method represented 98.92% removal efficiency under optimal conditions.•Throughout 60 days, the adsorbent was just leached 6 ppm Gly.
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•Bamboo based biochar/montmorillonite composite preparation.•Porous biochar acted as support to host particles of montmorillonite.•The composite exhibited much better compared to raw ...biochar via nitrates removal.
Biochar is a promising immobilization tool for various contaminants in liquid wastes, aqueous solutions and soils. To further improve the sorption characteristics, a biochar/montmorillonite composite was produced and synthesized in an experimental pyrolysis reactor, using bamboo as biomass feedstock. The composite was characterized by physico-chemical and structural methods (FTIR, SEM, SEM/EDX, SSA, Low temperature nitrogen adsorption method). Based on these methods, the successful preparation of a bamboo based biochar/montmorillonite composite preparation has been demonstrated. The particles of montmorillonite were distributed across the biochar surface. The adsorption studies for removal nitrates from aqueous solutions were investigated by a batch method at laboratory temperatures. The experimental data were fitted by three adsorption models (Langmuir, Freundlich and DR; R2 > 0.93). The maximum adsorption capacity achieved by biochar at pH 4, was about 5 mg g−1 and by biochar/montmorillonite composite 9 mg g−1. The results suggest that the bamboo-based biochar/montmorillonite composite can be used effectively in the treatment of industrial effluents or waste water containing anionic pollutants such as nitrates.
Katsarosite, ideally Zn(C
2
O
4
)·2H
2
O, named for Īraklīs Katsaros, is a new mineral found at the Esperanza Mine in the Kaminiza area of the Lavrion Mining District, Greece. Katsarosite usually ...occurs directly on sphalerite or embedded in jarosite and/or hydrozincite, often intimately intergrown with gypsum and overgrown by goslarite and/or epsomite. Crystal aggregates are mostly fine granular to earthy, with individual crystals being usually rounded with an average diameter of 30 µm, sometimes prismatic along 001 or platy, exhibiting the indistinct forms {100}, {001}, {110}, and {101}. Katsarosite is malleable with a Mohs hardness of 1½ – 2 and exhibits a perfect cleavage on {110}; the fracture is uneven in all other directions. The colour depends on the iron (Fe
2+
) content, ranging from pure white in almost Fe-free samples to yellow in Fe-rich specimens. It has a resinous luster and a white streak; no luminescence has been observed under either short- or long-wave ultraviolet radiation. Katsarosite is optically biaxial (+). Refractive indices measured at a wavelength of 589 nm are
n
α
= 1.488(2),
n
β
= 1.550(2),
n
γ
= 1.684(2), with 2
V
obs
= 71(3)°. Chemical analysis gave on average C
2
O
3
38.32 wt%, ZnO 38.99 wt%, FeO 1.92 wt%, and H
2
O 19.04 wt% (the latter was deduced based on the crystal-structure refinement), with traces of MgO and MnO. The new mineral is readily soluble in dilute acids. Katsarosite is monoclinic, space group
C
2/
c
, with unit-cell parameters
a
= 11.768(3),
b
= 5.3882(12),
c
= 9.804(2) Å,
β
= 127.045(8)°,
V
= 496.2(2) Å
3
(
Z
= 4). The strongest lines in the Gandolfi X-ray powder pattern
d
obs
in Å,
I
obs
/
I
100
, (
hkl
) are: 4.6745, 100, (200); 4.7678, 94, (20
2
¯
); 2.9533, 51, (40
2
¯
); 4.7030, 37, (1
1
¯
1
¯
); 3.9266, 33, (002); 3.5686, 27, (111); 2.6574, 22, (1
1
¯
3
¯
); 3.5992, 8, (1
1
¯
2
¯
); 2.7032, 4, (020). The crystal structure was refined based on single-crystal X-ray diffraction data to
R
(
F
) = 0.08. The observed mass density of 2.50(2) g cm
−3
compares well with the calculated value (2.508 g cm
−3
). Katsarosite belongs to the humboldtine group, whose crystal-structure type is well described for both isotypic minerals and synthetic compounds in the literature. The atomic arrangement in Zn(C
2
O
4
)·2H
2
O is characterized by chains consisting of isolated ZnO
6
octahedra which are alternately linked along 010 via oxalate anions. These chains are interconnected through hydrogen bonds only, with Ow···O (with Ow denoting the O atom of the H
2
O molecule) donor–acceptor distances of ~ 2.8 Å.
Zr
2
(OH)
2
(
X
O
4
)
3
·4H
2
O (
X
= S, Se), Zr(SO
4
)
2
·4H
2
O, and Zr(SeO
3
)
2
were synthesized at low-hydrothermal conditions from mixtures of Zr
2
O
2
(CO
3
)(OH)
2
, the respective acids, ...and minor amounts of water. While Zr
2
(OH)
2
(
X
O
4
)
3
·4H
2
O (
X
= S, Se) and Zr(SO
4
)
2
·4H
2
O form crystals up to several tenths of a mm, Zr(SeO
3
)
2
was mainly obtained as microcrystalline powder, single crystals rarely exceeded 10 μm in size. Samples were investigated by single-crystal X-ray techniques and in the case of Zr(SeO
3
)
2
also by X-ray powder diffraction. The compounds Zr
2
(OH)
2
(
X
O
4
)
3
·4H
2
O (
X
= S, Se) crystallize in the Ce
2
(OH)
2
(SO
4
)
3
·4H
2
O structure type (
C
2
/c
,
Z
= 4,
a
= 13.034(2) / 13.308(3),
b
= 6.500(1) / 6.683(2),
c
= 15.056(3) / 15.383(4) Å,
β
= 96.27(1) / 96.81(1)°,
V
= 1267.9(4) / 1358.5(6) Å
3
for
X
= S / Se, respectively). Tetragonal aniprisms Zr
8
O
8
are edge-connected to dimers that share corners with
X
O
4
tetrahedra forming a three-dimensional network. Zr(SO
4
)
2
·4H
2
O (
Fddd
,
Z
= 8,
a
= 5.498(1),
b
= 11.618(3),
c
= 25.893(6) Å,
V
= 1653.9(6) Å
3
) is isotypic with the respective selenate compound. Occasionally, pseudomerohedral twinning is observed, simulating a larger monoclinic
C
-centered unit cell. Again, tetragonal antiprisms Zr
8
O
8
are formed; however, they are corner-linked with SO
4
tetrahedra to Zr(SO
4
)
2
layers interconnected solely by hydrogen bonds. Zr(SeO
3
)
2
crystallizes in
P
2
1
/
c
, Z = 2;
a
= 4.9724(3),
b
= 8.5992(5),
c
= 6.9447(3) Å,
β
= 110.128(3)°,
V
= 278.81(3) Å
3
(unit cell from powder data) and belongs to the β-Sn(SeO
3
)
2
structure type established further for Ti(SeO
3
)
2
and Pb(SeO
3
)
2
. Isolated ZrO
6
octahedra share corners with the selenite groups forming a three-dimensional network.
Graphical abstract
PolyJIT: Polyhedral Optimization Just in Time Simbürger, Andreas; Apel, Sven; Größlinger, Armin ...
International journal of parallel programming,
12/2019, Volume:
47, Issue:
5-6
Journal Article
Stergiouite is a new mineral from the Plaka area in the northern part of the Lavrion Mining District, Greece. The mineral occurs as clusters of stacked, platy crystals, associated with galena, ...sphalerite, native arsenic and sulfur. The crystals are white to colorless, with a pearly luster and white streak. No luminescence under ultraviolet (UV) radiation is observed. Stergiouite is brittle and has a Mohs hardness of ~3. Chemical analysis gave As
2
O
5
42.93 wt%; Sb
2
O
5
2.45 wt%; CaO 10.90 wt%; ZnO 29.79 wt%; and H
2
O
calc
13.93 wt%, which corresponds to an empirical formula Ca
1.02
Zn
1.91
((As
0.95
Sb
0.08
)O
4
)
Σ2.03
· 4H
2
O. The ideal formula is CaZn
2
(AsO
4
)
2
· 4H
2
O. Stergiouite is monoclinic, space group
Pc
, with unit-cell parameters
a
9.416(2) Å;
b
5.300(1) Å;
c
10.893(2) Å;
β
91.767(10)°;
V
543.36(3) Å
3
;
Z
= 2. The strongest lines in the Gandolfi X-ray powder pattern
d
in Å, I/I
100
, (
hkl
) are: 9.406, 100, (100); 4.619, 80, (102), (110); 3.612, 35, (20
2
¯
); 3.494, 35, (112); 2.984, 60, (21
2
¯
); 2.922, 50, (212); 2.720, 20, (004); and 2.647, 25, (020). The crystal structure was refined based on single-crystal X-ray diffraction data to
R
1 = 0.046,
wR
2 = 0.093. The observed mass density of 3.1(2) g cm
−3
compares well with the calculated value (3.183 g cm
−3
). The framework structure of stergiouite is built up by one type of CaO
2
(H
2
O)
4
octahedron and each two ZnO
4
and AsO
4
tetrahedra. These polyhedra share common corners to form three- and four-membered rings. A system of hydrogen bonds (O–O range: 2.70–3.02 Å) further stabilizes the structure. The crystal structure of stergiouite is closely related to that of phosphophyllite Fe
6
Zn
2
4
(PO
4
)
2
· 4H
2
O as well as with members of the hopeite Zn
6
Zn
2
4
(PO
4
)
2
· 4H
2
O group. Stergiouite is named in honour of Vasilis Stergiou (born 1958) in recognition of his contributions to the mineralogy of the Lavrion deposits.
The structural recovery upon heat treatment of a highly metamict, actinide-rich zircon (U≈6000 ppm) has been studied in detail using a range of techniques including X-ray powder diffraction, Raman ...spectroscopy, SHRIMP ion probe, electron microprobe, transmission electron microscopy and cathodoluminescence analysis. The structural regeneration of the amorphous starting material depends on random nucleation. It starts between 800 and 950 °C when amorphous ZrSiO
4 decomposes to form crystalline ZrO
2 and amorphous SiO
2. At around 1100 °C, well-crystallised ZrSiO
4 grows at the expense of the oxides. U has been retained in the newly grown zircon whereas Pb was evaporated during the heat treatment. This process is in marked opposition to the reconstitution of moderately metamict minerals, which experience a gradual recovery controlled by the epitaxial growth at the crystalline–amorphous boundaries. Both of these recovery processes are not the direct inverse of metamictisation. The structural regeneration was found to be connected with a significant increase in the emission of CL. In all cases (annealing heavily damaged zircon and moderately damaged zircon and monazite), we observe that the final, well-crystallised annealing products emit more intense CL than their radiation-damaged starting minerals, although having almost identical elemental composition. Our observations are taken as evidence that the CL is not only determined by the chemical composition of the sample but is also strongly controlled by structural parameters such as crystallinity or the presence of defect centres.
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