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1.
Sci Rep ; 14(1): 10914, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38740821

ABSTRACT

Waste from construction and demolition (also known as CDW) is one of the most harmful environmental issues. This study's primary goal is to produce new mortar and brick materials from recycled concrete powder (RCP) and recycled brick powder (RBP), two of the most popular CDW. Geopolymeric mortar and brick samples were produced by passing RCP and RBP through sieve No. 50 (with sand filler if necessary) and combining them with an alkaline solution made of water glass (WG) and NaOH. In this study, the mixture was then cured for three days at 80 °C in an oven. The effects of filler, RBP amount, WG amount, and the concentration of NaOH alkaline solution on the samples' strength were examined. Additionally, XRF and SEM/XRD tests were performed to verify the materials' composition and microstructure. The mechanical strength of the samples showed an increase with the increase of RCP values, so the brick sample with filler showed the highest compressive strength, measuring 59.53 MPa. The study's samples exhibited strong mechanical properties. Additionally, all of the bricks' water absorption fell within the standard range. In summary, according to different standards, both waste concrete and waste brick can be used to produce geopolymer materials especially bricks for construction and paving purposes.

2.
J Environ Manage ; 350: 119545, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-37995482

ABSTRACT

A novel octahedral distorted coordination complex was formed from a copper transition metal with a bidentate ligand (1,10-Phenanthroline) and characterized by Ultraviolet-visible spectroscopy, Ultraviolet-visible diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller, Field emission scanning electron microscopy, and Single-crystal X-ray diffraction. The Hirshfeld surface and fingerprint plot analyses were conducted to determine the interactions between atoms in the Cu(II) complex. DFT calculations showed that the central copper ion and its coordinated atoms have an octahedral geometry. The Molecular electrostatic potential (MEP) map indicated that the copper (II) complex is an electrophilic compound that can interact with negatively charged macromolecules. The HOMO-LUMO analysis demonstrated the π nature charge transfer from acetate to phenanthroline. The band gap of [Cu(phen)2(OAc)]·PF6 photocatalyst was estimated to be 2.88 eV, confirming that this complex is suitable for environmental remediation. The photocatalytic degradation of erythrosine, malachite green, methylene blue, and Eriochrome Black T as model organic pollutants using the prepared complex was investigated under visible light. The [Cu(phen)2(OAc)]·PF6 photocatalyst exhibited degradation 94.7, 90.1, 82.7, and 74.3 % of malachite green, methylene blue, erythrosine, and Eriochrome Black T, respectively, under visible illumination within 70 min. The results from the Langmuir-Hinshelwood kinetic analysis demonstrated that the Cu(II) complex has a higher efficiency for the degradation of cationic pollutants than the anionic ones. This was attributed to surface charge attraction between photocatalyst and cationic dyes promoting removal efficiency. The reusability test indicated that the photocatalyst could be utilized in seven consecutive photocatalytic degradation cycles with an insignificant decrease in efficiency.


Subject(s)
Copper , Environmental Pollutants , Copper/chemistry , Methylene Blue/chemistry , Kinetics , Erythrosine , Light , Coloring Agents/chemistry , Catalysis
3.
Sci Rep ; 13(1): 19042, 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37923911

ABSTRACT

Sodium chloride (NaCl), commonly known as salt, is a substance that is utilized in a variety of businesses, including the tourism and construction industries. Therefore, the main purpose of this article is to accommodate a salt-based building material called NaCl-binder for tourist and industrial applications. By utilizing salt mortar with varying grain sizes, food-grade corn starch as an exclusive binder agent (without using any non-starch binder), and water under microwave-cured conditions, environmentally friendly hydrophobic hybrid NaCl-binder samples with low bulk density were successfully produced. The fabrication of these samples involved an inventive utilization of small quantities of starch. This study evaluated the impact of microwave exposure time on the strength of salt samples, particle interconnectivity and chemical composition using SEM, XRD, and XRF analyses. The compressive strength of the samples showed a remarkable increase, with a 600% improvement when using 0 to 1% corn starch, and a 137% increment when using 1 to 10% corn starch, indicating a lower rate of increment with higher starch consumption. A key aspect of this research is the significant reduction in starch consumption compared to other corn starch-based materials during the manufacturing process of the incorporated materials, highlighting its novelty and importance.

4.
J Colloid Interface Sci ; 619: 1-13, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35367923

ABSTRACT

Herein, we have developed Ln2Ce2O7 (Ln = Er, Ho) ceramic nanostructures through a rapid and green sonochemical approach and scrutinized their photocatalytic efficiency toward degradation of toxic pollutants under sunlight. Salvia rosmarinus extract is utilized as a morphology-directing agent in the sono-synthesis of the nanostructured Ln2Ce2O7 (Ln = Er, Ho), for the first time. Comprehensive characterization utilizing different techniques demonstrated that introducing of rare-earth metals, erbium and holmium, affected the textural, morphological, and optical features of the nanostructured ceria. The energy gap for pure cerium dioxide nanostructure was estimated to be 3.09 eV, while the energy gap for Ho2Ce2O7 and Er2Ce2O7 nanostructure was estimated at 2.9 and 2.66 eV, respectively. The narrowing of the energy gap was observed as a result of the introduction of rare-earth metals, erbium and holmium, especially erbium, into the nanostructured ceria. Investigation of the photocatalytic decomposition of various contaminants revealed that the introduction of erbium has remarkably enhanced the photocatalytic activity of nanostructured ceria. High photocatalytic performance (98.9%) and rate constant (0.0727 min-1) was observed for the Er2Ce2O7 nanostructure in the removal of eriochrome Black T. Improving the optical features of ceria nanostructure as well as enhancing its specific area were reasons that could increase the photocatalytic efficiency. The photocatalytic decomposition reactions in the removal of toxic contaminants were well accorded with the Pseudo-first order reaction kinetics. Besides, the nanostructured Er2Ce2O7 maintained its efficiency after ten reaction cycles and did not denote any notable decline in efficiency. The use of this novel porous nanostructure can be a potentially efficient solution for water treatment.


Subject(s)
Lanthanoid Series Elements , Metals, Rare Earth , Nanostructures , Catalysis , Erbium , Holmium , Sunlight
5.
Ultrason Sonochem ; 82: 105892, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34959201

ABSTRACT

The present study is on the fabrication of new photocatalytic nanocomposites (Dy2O3-SiO2) employing a basic agent, tetraethylenepentamine (Tetrene), through a simple, efficient and, quick sonochemical approach. The features of the fabricated photocatalytic nanocomposite were examined employing a variety of microscopic and spectroscopic methods such as XRD, EDS, TEM, FTIR, DRS, and FESEM. The outcomes of morphological studies demonstrated that by proper tuning of sonication time and ultrasonic power (10 min and 400 W), a porous nanocomposite composed of sphere-shaped nanoparticles with a particle size in the range of 20 to 60 nm could be fabricated. The energy gap for the binary Dy2O3-SiO2 nanophotocatalyst was determined to be 3.41 eV, making these nanocomposite favorable for removing contaminants. The photocatalytic performance of the optimal nanocomposite sample was tested for photodecomposition of several contaminants including erythrosine, thymol blue, eriochrome black T, Acid Red 14, methyl orange, malachite green, and Rhodamine B. The binary Dy2O3-SiO2 nanophotocatalyst exhibited superior efficiency toward the decomposition of the studied contaminants. It was able to degrade the erythrosine pollutant more effectively (92.9%). Optimization studies for the photocatalytic decomposition of each contaminant demonstrated that the best performance could be achieved at a specific amount of contaminant and nanocatalyst. Trapping experiments illustrated that hydroxyl radicals were more effectively involved in the decomposition of contaminant molecules by Dy2O3-SiO2 nanophotocatalyst.

6.
Ultrason Sonochem ; 72: 105420, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33385636

ABSTRACT

Water contamination has turned into a critical global concern that menaces the entire biosphere and has a notable effect on the lives of living beings and humans. As a proper and environmentally friendly solution, visible-light photocatalysis technology has been offered for water contamination removal. There is a strong interest in the design of the efficient catalytic materials that are photoactive with the aid of visible light. Herein, to fabricate a highly efficient photocatalyst for removal of organic pollution in water, a facile and swift sonochemical route employed for creation of the spindle shaped PbWO4 nanostructure with the aid of an environmentally friendly capping agent (maltose) for the first time. To optimize the efficiency, dimension and structure of lead tungstate, various effective factors such as time, dose of precursors, power of ultrasound waves and kind of capping agents were altered. The attributes of PbWO4 samples were examined with the aid of diverse identification techniques. The produced lead tungstate samples in role of visible-light photocatalyst were applied to remove organic pollution in water. The kinds of pollutants, dose and type of catalyst were examined as notable factors in the capability to eliminate contaminants. Very favorable catalytic yield and durability were demonstrated by spindle-shaped PbWO4 nanostructure (produced at power of 60 W for 10 min and with usage of maltose). Usage of ultrasonic irradiation could bring to improvement of catalytic yield of PbWO4 to 93%. Overall, the outcomes could introduce the spindle-shaped PbWO4 nanostructure as an efficient substance for eliminating water contamination under visible light.

7.
RSC Adv ; 11(63): 40100-40111, 2021 Dec 13.
Article in English | MEDLINE | ID: mdl-35494113

ABSTRACT

Designing and fabricating an efficient photocatalytic compound with an appropriate band gap to eliminate toxic contaminants is necessary to remediate the environment. This article presents the development of a new type of nanostructure, Lu2Cu2O5-Lu2O3 nanocomposites to photo-catalytically degrade different kinds of toxic pollutants under sunlight. The oxide nanocomposites were fabricated via a quick and eco-friendly approach. In order to fabricate oxide nanostructures with appropriate features in terms of morphology and particle size, the effects of the kind of green reactant and its quantity were examined. Amylum was an appropriate and green reactant for the efficient synthesis of Lu2Cu2O5-Lu2O3 nanobundles with the most organized morphology. The features of Lu2Cu2O5-based nanostructures were carefully investigated utilizing multiple characterization methods. Then, the catalytic role of the fabricated nanobundles was evaluated for the removal of various kinds of toxic contaminants. The effects of the quantity of photocatalytic nanostructure, the concentration of the contaminant compound, and the type of light source in the catalytic degradation process were screened. The findings of this research demonstrated that utilizing 0.05 g of Lu2Cu2O5-Lu2O3 nanobundles, 98.5% of the contaminant with a concentration of 10 ppm can be degraded in 2 h under ultraviolet light irradiation. The experimental results also certified that, during the photocatalytic pathway, superoxide radicals play a meaningful role in the elimination of toxic pollutants. To our knowledge, this is the first report of the fabrication of Lu2Cu2O5-Lu2O3 nanocomposite through a facile and eco-friendly approach and its photocatalytic efficiency.

8.
Ultrason Sonochem ; 71: 105376, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33142222

ABSTRACT

Here, we offer an easy and eco-friendly sonochemical pathway to fabricate Nd2Zr2O7 nanostructures and nanocomposites with the help of Morus nigra extract as a new kind of capping agent. For the first time, the performance of Nd2Zr2O7-based ceramic nanostructure materials has been compared upon NOx abatement. Diverse kinds of techniques have been employed to specify purity and check the attributes of the fabricated Nd2Zr2O7-based nanostructurs by Morus nigra extract. Outcomes revealed the successful fabrication of Nd2Zr2O7 nanostructures and nanocomposites applying Morus nigra extract through sonochemical pathway. All nanostructured samples have been fabricated through ultrasonic probe with power of 60 W (18 KHz). Further, the fabricated Nd2Zr2O7-based ceramic nanostructure materials can be applied as potential nanocatalysts with appropriate performance for propane-SCR-NOx, since the conversion of NOx to N2 for the best sample (Nd2Zr2O7-ZrO2 nanocomposite) was 70%. In addition, in case of Nd2Zr2O7-ZrO2 nanocomposite, the outlet quantity of CO as an unfavorable and unavoidable product was lower than the rest.

9.
J Environ Manage ; 233: 107-119, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30576958

ABSTRACT

A simple and clean synthesis for Nd2Sn2O7-SnO2 nanocomposites as high-efficiency visible-light responsive photocatalyst is described applying extract of pineapple, for the first time. As novel and non-toxic biofuel, extract of pineapple, is employed to fabricate Nd2Sn2O7-SnO2 nanocomposites through an environment-friendly procedure. The findings denote that the applied biofuel can play a meaningful role as capping agent during preparation of Nd2Sn2O7-SnO2 nanocomposites. Depending on the applied dosage of pineapple extract as well as time for fabrication, the grain size, photocatalytic yield and morphology of Nd2Sn2O7-SnO2 structures changed. A suite of identification methods like XRD, TEM, EDS, DRS, BET and FESEM are utilized for investigation of the produced Nd2Sn2O7-SnO2 nanocomposites. Nd2Sn2O7-SnO2 structures are utilized as visible-light responsive photocatalyst to degrade the rhodamine B and eosin Y contaminants. The produced Nd2Sn2O7-SnO2 nanocomposites have been found to be very effective as visible-light responsive photocatalyst to degrade contaminants which may bring to environmental pollution.


Subject(s)
Environmental Pollutants , Water , Catalysis , Photolysis , Tin Compounds
10.
Ultrason Sonochem ; 42: 171-182, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29429658

ABSTRACT

Nd2O3-SiO2 nanocomposites with enhanced photocatalytic activity have been obtained through simple and rapid sonochemical route in presence of putrescine as a new basic agent, for the first time. The influence of the mole ratio of Si:Nd, basic agent and ultrasonic power have been optimized to obtain the best Nd2O3-SiO2 nanocomposites on shape, size and photocatalytic activity. The produced Nd2O3-SiO2 nanocomposites have been characterized utilizing XRD, EDX, TEM, FT-IR, DRS and FESEM. Application of the as-formed Nd2O3-SiO2 nano and bulk structures as photocatalyst with photodegradation of methyl violet contaminant under ultraviolet illumination was compared. Results demonstrated that SiO2 has remarkable effect on catalytic performance of Nd2O3 photocatalyst for decomposition. By introducing of SiO2 to Nd2O3, decomposition efficiency of Nd2O3 toward methyl violet contaminant under ultraviolet illumination was increased.

11.
Ultrason Sonochem ; 39: 452-460, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28732968

ABSTRACT

In this work, highly photocatalytically active Ho2O3-SiO2 nanocomposites have been designed and applied for decomposition of methylene blue pollutant. Ho2O3-SiO2 nanocomposites have been produced by new, quick and facile sonochemical process with the aid of tetramethylethylenediamine as a novel basic agent for the first time. The effect of the kind of basic agent, ultrasonic time and dosage of Ho source on the grain size, photocatalytic behavior and shape of the Ho2O3-SiO2 nanocomposites have been evaluated for optimization the production condition. FESEM, EDX, FT-IR, DRS, XRD and TEM have been applied to characterize the as-produced Ho2O3-SiO2 nanocomposites. Use of the as-produced Ho2O3-SiO2 nanocomposites as photocatalyst via destruction of methylene blue pollutant under UV illumination has been compared. It was observed that SiO2 has notable impact on catalytic activity of holmium oxide photocatalyst for destruction. Introducing of SiO2 to holmium oxide can enhance destruction efficiency of holmium oxide to methylene blue pollutant under ultraviolet light.

12.
PLoS One ; 12(6): e0158549, 2017.
Article in English | MEDLINE | ID: mdl-28582420

ABSTRACT

Highly photocatalytically active copper chromite nanostructured material were prepared via a novel simple hydrothermal reaction between [Cu(en)2(H2O)2]Cl2 and [Cr(en)3]Cl3.3H2O at low temperature, without adding any pH regulator or external capping agent. The as-synthesized nanostructured copper chromite was analyzed by transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy, energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Results of the morphological investigation of the as-synthesized products illustrate that the shape and size of the copper chromite depended on the surfactant sort, reaction duration and temperature. Moreover, the photocatalytic behavior of as-obtained copper chromite was evaluated by photodegradation of acid blue 92 (anionic dye) as water pollutant.


Subject(s)
Chromium Compounds/chemistry , Copper/chemistry , Nanostructures/chemistry , Naphthalenes/isolation & purification , Water Pollutants, Chemical/isolation & purification , Biodegradation, Environmental , Catalysis , Fresh Water/chemistry , Hot Temperature , Humans , Nanostructures/ultrastructure , Particle Size , Photochemical Processes , Surface Properties , Temperature
13.
J Colloid Interface Sci ; 497: 298-308, 2017 07 01.
Article in English | MEDLINE | ID: mdl-28288376

ABSTRACT

Dy2Sn2O7-SnO2 nanocomposites were synthesized through a facile way utilizing propane-1,2-diol as novel polymerization agent and trimesic acid as new stabilization agent. Effects of different polymerization agents, calcination temperature and various stabilization agents on the size and shape of the Dy2Sn2O7-SnO2 nanocomposites were investigated. It was found that changing these synthesis factors has great role in controlling size and shape of Dy2Sn2O7-SnO2 nanocomposites. The as-produced Dy2Sn2O7-SnO2 nanostructures were analyzed using FT-IR, HRTEM, DR-UV-vis, EDS, XRD, and FESEM. This is the first attempt on the investigation of photocatalytic behavior of nanostructured Dy2Sn2O7-SnO2. The influences of Dy2Sn2O7-SnO2 amount and type of illumination light on the photocatalytic behavior of the nanocrystalline Dy2Sn2O7-SnO2 were also investigated. The ability for the decomposition of the water pollutants including eosin Y, eriochrome black T, erythrosine and methyl orange were studied through photocatalytic experiments.

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