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1.
J Environ Manage ; 351: 119614, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38043309

ABSTRACT

This comprehensive review delves into the forefront of wastewater treatment technology, with a specific focus on the revolutionary concept of Zero Liquid Discharge (ZLD). (ZLD), underpinned by a sustainable ethos, aspires to accomplish total water reclamation, constituting a pivotal response to pressing environmental issues. The paper furnishes a historical panorama of (ZLD), elucidating its motivating factors and inherent merits. It navigates a spectrum of (ZLD) technologies encompassing thermal methodologies, (ZLD) synergized with Reverse Osmosis (RO), High-Efficiency Reverse Osmosis (HERO), Membrane Distillation (MD), Forward Osmosis (FO), and Electrodialysis Reversal (EDR). Moreover, the study casts a global purview over the deployment status of (ZLD) systems in pursuit of resource recovery, accentuating nations such as the United States, China, India, assorted European Union members, Canada, and Egypt. Meticulous case studies take center stage, underscoring intricate scenarios involving heavily contaminated effluents from challenging sectors including tanneries, textile mills, petroleum refineries, and paper mills. The report culminates by distilling sagacious observations and recommendations, emanating from a collaborative brainstorming endeavor. This compendium embarks on an enlightening journey through the evolution of wastewater treatment, (ZLD)'s ascendancy, and its transformative potential in recalibrating water management paradigms while harmonizing industrial progress with environmental stewardship.


Subject(s)
Resilience, Psychological , Water Purification , Wastewater , Water , Membranes, Artificial , Osmosis , Technology , Water Supply
2.
Sci Rep ; 13(1): 7034, 2023 Apr 29.
Article in English | MEDLINE | ID: mdl-37120645

ABSTRACT

Powder metallurgy (PM) is a technique that involves the manufacturing of metal powders and their consolidation into finished products or components. This process involves the mixing of metal powders with other materials such as ceramics or polymers, followed by the application of heat and pressure to produce a solid, dense material. The use of PM has several advantages over traditional manufacturing techniques, including the ability to create complex shapes and the production of materials with improved properties. Cu-TiO2 composite materials are of great interest due to their unique properties, such as high electrical conductivity, improved mechanical strength, and enhanced catalytic activity. The synthesis of Cu-TiO2 composites using the PM technique has been gaining popularity in recent years due to its simplicity, cost-effectiveness, and ability to produce materials with excellent homogeneity. The novelty of using the PM technique for the preparation of Cu-TiO2 composite lies in the fact that it enables the production of materials with controlled microstructures and optical properties. The microstructure of the composite can be fine-tuned by controlling the particle size and distribution of the starting powders, as well as the processing parameters such as temperature, pressure, and sintering time. The optical properties of the composite can also be tailored by adjusting the size and distribution of the TiO2 particles, which can be used to control the absorption and scattering of light. This makes Cu-TiO2 composites particularly useful for applications such as photocatalysis and solar energy conversion. In summary, the use of Powder Metallurgy for the preparation of Cu-TiO2 composite is a novel and effective technique for producing materials with controlled microstructures and optical properties. The unique properties of Cu-TiO2 composites make them attractive for a wide range of applications in various fields, including energy, catalysis, and electronics.

4.
Sci Rep ; 12(1): 20974, 2022 12 05.
Article in English | MEDLINE | ID: mdl-36470902

ABSTRACT

The major objective of this study was to examine the viability of using 5, 10, or 15 mass% of Activated Alum Sludge waste (AAS) instead of Ordinary Portland Cement (OPC) as a pozzolanic ingredient in concrete. This fundamental inquiry framed the investigation and OPC-AAS-hardened composites were studied to see whether they may benefit from inexpensive nanocomposites in terms of improved physical properties, mechanical strength, and resistance to heat and flame. The investigation set out to see how inexpensive nanocomposite might be put to use and the nanoparticles of CuFe2O4 spinel with an average size of less than 50 nm were successfully manufactured. Many different OPC-AAS-hardened composites benefit from the addition of CuFe2O4 spinel, which increases the composites' resistance to fire and enhances their physicomechanical properties at roughly average curing ages. Synthesized CuFe2O4 spinel was shown to have desirable characteristics by TGA/DTG and XRD. By using these methods, we were able to identify a broad variety of hydration yields, including C-S-Hs, C-A-S-Hs, C-F-S-Hs, and Cu-S-Hs, that enhance the physicomechanical properties and thermal resistivity of OPC-AAS-hardened composites as a whole. The composite material comprising 90% OPC, 10% AAS waste, and 2% CuFe2O4 has several positive economic and environmental outcomes.


Subject(s)
Construction Materials , Sewage , Cost-Benefit Analysis
5.
Sci Rep ; 12(1): 20611, 2022 11 29.
Article in English | MEDLINE | ID: mdl-36446843

ABSTRACT

The goal of this research is to determine what chemicals are present in two different extracts (hexane and acetone) of Vicia faba (family Fabaceae, VF) peels and evaluate their effectiveness as a corrosion inhibitor on mild steel in a saline media containing 3.5% sodium chloride. Gas chromatography-mass spectrometry (GC/MS) was used to determine the composition of various extracts. It was determined that fourteen different chemicals were present in the hexane extract, the most prominent of which were octacosane, tetrasodium tetracontane, palmitic acid, and ethyl palmitate. Heptacosane, lauric acid, myristic acid, ethyl palmitate, and methyl stearate were some of the 13 chemicals found in the acetone extract. Using open circuit potential, potentiodynamic polarisation, and electrochemical impedance spectroscopic techniques, we can approximate the inhibitory effects of (VF) extracts on mild steel. The most effective inhibitory concentrations were found to be 200 ppm for both the hexane and acetone extracts (97.84% for the hexane extract and 88.67% for the acetone extract). Evaluation experiments were conducted at 298 K, with a 3.5% (wt/v) NaCl content and a flow velocity of about 250 rpm. Langmuir adsorption isotherm shows that the two extracts function as a mixed-type inhibitor in nature. Docking models were used to investigate the putative mechanism of corrosion inhibition, and GC/MS was used to identify the major and secondary components of the two extracts. Surface roughness values were calculated after analyzing the morphology of the metal's surface with and without (VF) using a scanning electron microscope (SEM). The results showed that throughout the surface of the mild steel, a thick adsorbate layer was formed. Quantum chemical calculations conducted on the two extracts as part of the theoretical research of quantum chemical calculation demonstrated a connection between the experimental analysis results and the theoretical study of the major chemical components.


Subject(s)
Steel , Vicia faba , Corrosion , Hexanes , Fatty Acids , Water , Cost-Benefit Analysis , Acetone
7.
Sci Rep ; 12(1): 12536, 2022 Jul 22.
Article in English | MEDLINE | ID: mdl-35869239

ABSTRACT

The purpose of this work lies in the use of ionic liquids as corrosion inhibitors due to the difficulty in some oil fields with the solubility of corrosion inhibitors and these materials can be miscible with water and thus provide a solution to such problems in the industry. The second purpose is concerned with the lower toxicity of these compounds compared with the most common corrosion inhibitors. The study covered the corrosion inhibition performance of the ionic liquid 1-butyl-3-methylimidazolium trifluoromethyl sulfonate ([BMIm]TfO) for carbon steel in 3.5% NaCl solutions. The study comprised electrochemical, adsorption, and quantum chemical investigations. The results manifested that [BMIm]TfO can be considered a promising corrosion inhibitor and the inhibition efficacy intensifies as the concentration rises. The observed inhibitive effect can be correlated to the adsorption of the ionic liquid species and the creation of protecting films on the surface. The mode of adsorption follows the Langmuir adsorption isotherm. The polarization results showed that the ionic liquid [BMIm]TfO functions as a mixed inhibitor. Reliance of the corrosion influence on the temperature in the existence and absence of [BMIm]TfO was demonstrated in the temperature range of 303-333 K using polarization data. Activation parameters were determined and discussed. The observed inhibition performance of [BMIm]TfO was correlated with the electronic properties of the ionic liquid using a quantum chemical study.

8.
Appl Biochem Biotechnol ; 194(9): 4105-4134, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35633433

ABSTRACT

Eichhornia crassipes root powder (ECRP) has been used to remove ammonia from aqueous solutions. The biosorption factors such as biosorbent dosage, pH, initial ammonia concentration, and contact time have been considered in batch conditions. The optimal conditions, at pH (6), sorbent dose 5 g/l, time (30 min) ammonia concentration (10 mg/l). Langmuir is better suited than Freundlich isotherm. The kinetic models Thomas, Yoon-Nelson, and Bohart-Adams were applied. These models showed that the adsorption capacity decreased with flow rate increases as follows: 32.57, 31.82, 31.25, and 30.17 mg/g, respectively, at a flow rate 10, 15, 20, and 25 ml/min. The root powder of Eichhornia crassipes was used to treat specific drainage wastewater obtained from the Sabal drain at Menoufia, Egypt. The average efficiency of ammonia removal was 87% per batch adsorption method at pH value = 7.5, sorbent dose 5 g/l, uptake period (30 min), and primary load 7.1 mg/l; however, ammonia removal by column continuous adsorption method exceeded 94%. In addition, ECRP is efficient in removing arsenic, sulfate, nitrates, nitrite, silica, iron, manganese, copper, zinc, aluminum, and lead from actual sewage wastewater, in addition to removing more than 75% COD.


Subject(s)
Ammonia , Wastewater , Water Pollutants, Chemical , Adsorption , Hydrogen-Ion Concentration , Kinetics , Powders , Water Pollutants, Chemical/analysis
9.
J Environ Manage ; 219: 325-331, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-29753240

ABSTRACT

A potential and cost-effective treatment method utilizing thermally activated bentonite was evaluated for the treatment of highly loaded real petroleum processing wastewater (COD = 4500 mg/L) in order to reduce its COD and improve the corrosion properties. A save discharging COD limit of the treated effluent (800 mg/L) is achieved by using 6 g/L of calcinated bentonite after reaching the steady state (1 h of shaking) at pH 5. The durability of bentonite is proved. The corrosion behavior of the treated wastewater was investigated for mild steel by using electrochemical and weight loss measurements. The results proved that the corrosion rate of the wastewater was slightly reduced after the treatment process. More improvement of the corrosion resistance was achieved by adding sodium hexa-meta-phosphate (SHMP) corrosion inhibitor to the treated water. Tri-methyl ammonium bromide (CTAB) biocide was also added before discharging into municipal networks.


Subject(s)
Petroleum , Wastewater , Corrosion , Steel , Waste Disposal, Fluid
10.
Scand J Immunol ; 57(2): 125-34, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12588658

ABSTRACT

We have used a synthetic-peptide approach to map epitope regions of the Mycobacterium tuberculosis ESAT-6 antigen recognized by human T cells in relation to major histocompatibility complex (MHC) restriction. ESAT-6-specific CD4+ T-cell lines were established by stimulating peripheral blood mononuclear cells from 25 HLA-DR-typed tuberculosis patients with complete antigen in vitro. The established T-cell lines were then screened for proliferation and interferon-gamma (IFN-gamma) secretion in response to eight overlapping 20-mer peptides covering the ESAT-6 sequence. The response of the T-cell lines to ESAT-6 and peptides from a human leucocyte antigen (HLA)-heterogeneous group of donors suggested the presence of multiple epitopes and promiscuous recognition of the antigen. Analysis of antigen and peptide recognition in the presence of anti-HLA class I and class II antibodies suggested that the T-cell lines recognized ESAT-6 in association with HLA-DR and -DQ molecules. Furthermore, testing of selected T-cell lines with ESAT-6 and the peptides in the presence of autologous and allogeneic HLA-DR- and -DQ-typed antigen-presenting cells identified HLA-DR2, -DR52 and -DQ2 amongst the HLA molecules involved in the presentation of ESAT-6 and its peptides to human Th1 cells. In addition, the T-cell lines were cytotoxic for monocytes and macrophages pulsed with ESAT-6 and peptides. In conclusion, the recognition of ESAT-6 by IFN-gamma-secreting and cytotoxic CD4+ T cells in association with frequently expressed HLA class II molecules supports the application of this antigen to either specific diagnosis or subunit vaccine design.


Subject(s)
Antigens, Bacterial/immunology , CD4-Positive T-Lymphocytes/immunology , HLA-DQ Antigens/immunology , HLA-DR Antigens/immunology , Mycobacterium tuberculosis/immunology , Th1 Cells/immunology , Amino Acid Sequence , Bacterial Proteins , Epitope Mapping , Humans , Interferon-gamma/biosynthesis , Molecular Sequence Data , Peptides/immunology , T-Lymphocytes, Cytotoxic/immunology
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