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1.
Polymers (Basel) ; 15(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36616375

RESUMEN

The current energy crisis and waste management problems have compelled people to find alternatives to conventional non-renewable fuels and utilize waste to recover energy. Pyrolysis of plastics, which make up a considerable portion of municipal and industrial waste, has emerged as a feasible resolution to both satisfy our energy needs and mitigate the issue of plastic waste. This study was therefore conducted to find a solution for plastic waste management problems, as well as to find an alternative to mitigate the current energy crisis. Pyrolysis of five of the most commonly used plastics, polyethylene terephthalate (PET), high- and low-density polyethylene (HDPE, LDPE), polypropylene (PP), and polystyrene (PS), was executed in a pyrolytic reactor designed utilizing a cylindrical shaped stainless steel container with pressure and temperature gauges and a condenser to cool down the hydrocarbons produced. The liquid products collected were highly flammable and their chemical properties revealed them as fuel alternatives. Among them, the highest yield of fuel conversion (82%) was observed for HDPE followed by PP, PS, LDPE, PS, and PET (61.8%, 58.0%, 50.0%, and 11.0%, respectively). The calorific values of the products, 46.2, 46.2, 45.9, 42.8 and 42.4 MJ/kg for LPDE, PP, HPDE, PS, and PET, respectively, were comparable to those of diesel and gasoline. Spectroscopic and chromatographic analysis proved the presence of alkanes and alkenes with carbon number ranges of C9-C15, C9-C24, C10-C21, C10-C28, and C9-C17 for PP, PET, HDPE, LDPE, and PS, respectively. If implemented, the study will prove to be beneficial and contribute to mitigating the major energy and environmental issues of developing countries, as well as enhance entrepreneurship opportunities by replicating the process at small-scale and industrial levels.

2.
Environ Technol ; 42(3): 444-458, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31185882

RESUMEN

Current investigation has for the first time synthesized chromium sulphide diethyldithiocarbamate [Cr2S3(Et2DTC)] complex utilizing diethyldithiocarbamate (DDTC) utilizing single source precursor method. Thin films of bilayer chromium sulphide diethyldithiocarmate and molybdenum disulphide [Cr2S3-MoS2(Et2DTC)] were deposited on the fluorine doped tin oxide (FTO) substrate by physical vapour deposition (PVD). Synthesized complex and bilayer were characterized by Xray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrophotometry (UV-Vis), and scanning electron microscopy (SEM) for exploration of the compositional, optical, crystalline and morphological parameters, respectively. FT-IR peaks expressed the chelation of [Cr2S3(Et2DTC)] expressing interactions between chromium sulphide and the ligand. The band gaps obtained from Tauc plot were 3.89 (direct) and 3.38 eV (indirect), respectively for Cr2S3(Et2DTC) complex. The direct and indirect band gap of 3.75 and 3.35 eV, respectively, were obtained for [Cr2S3-MoS2(Et2DTC)] bilayer thin films. Average crystallite size of 13 (hexagonal orientation) and 13.4 (orthorhombic orientation) nm and for Cr2S3(Et2DTC) complex and [Cr2S3-MoS2(Et2DTC)] bilayer thin films expressed from XRD. SEM micrographs expressed cannular and rod protrusions for Cr2S3-DDTC complex and smoother and unvarnished surficial characteristics for [Cr2S3-MoS2(Et2DTC)] bilayer thin films corresponding to compactness and uniformity of the films. Furthermore, [Cr2S3-MoS2(Et2DTC)] also expressed remarkable electrochemical aspects of the current generation and operational stability of analysed through 5760 s at 100 mA analysed via linear sweep voltammetry and chronoamperometry. The fabricated films can be efficiently used in optoelectronic devices. Current work can be extended to the optimization of bilayer thin films fabrication for achieving an alleviation in the band gaps.


Asunto(s)
Molibdeno , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
3.
Environ Sci Pollut Res Int ; 27(16): 19543-19560, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32219656

RESUMEN

Eco-degradative features associated with the modern agriculture due to utilization of toxic agro-chemicals and intensified technologies need an urgent attention. Considering this need for eco-curativeness and eco-efficiency, current has for the first time employed an integrated farming system (IFS) through designing an appropriate assemblage of vegetables, poultry, and fish (VPF) and investigated its applied scale practicability in addition to the its role in the enhancement of the productivity and environmental quality maintenance. The practical employment of VPF model resulted in the remarkable improvement of soil fertility through an increment in the essential nutrient quantity. Physicochemical analysis of the soils expressed an improvement in the treated samples, i.e., pH (7.31), EC (0.92 dS/m), organic matter (2.97%), nitrogen (2.1 mg/kg), phosphorous (120.3 mg/kg), potassium (322 mg/kg), calcium (1482.0 mg/kg), and magnesium (471.5 mg/kg). Furthermore, ecological detoxification was expressed in form of lower heavy metals (HM) in the experimental soils. At the early plantation stage, HM concentration in the soils modified with nutrient-rich water signified considerably lower pattern with trend, i.e., Cd < Zn < Ni

Asunto(s)
Metales Pesados/análisis , Contaminantes del Suelo/análisis , Agricultura , Animales , Empleo , Monitoreo del Ambiente , Suelo , Verduras
4.
Environ Sci Pollut Res Int ; 27(9): 9669-9685, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31925686

RESUMEN

Silver nanoparticles were fabricated in the presence and absence of light with silver nitrate and aqueous extract of Prunus cerasifera leaf via facile and one-pot green method. P. cerasifera leaf extract reduced and stabilized the nanoparticles with phytometabolites expunging the need for addition of external reducing agents. Optimized silver nanoparticle syntheses was done with variations in leaf extract concentration, time, temperature, and molarity for deciphering the photocatalytic, antifungal, and antibacterial potential of synthesized nanoparticles. Optical, compositional, and morphological analyses of the synthesized nanoparticles were done by UV-visible spectrometry (UV-Vis), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Formation of silver nanoparticles was confirmed firstly through UV-Vis by exhibition of peaks with 400-450 nm. FTIR confirmed the presence of major organic groups responsible for reduction of nanoparticles. AFM confirmed the spherical morphology of the synthesized nanoparticles with remarkable dispersion without any agglomeration. Phytochemical analysis for P. cerasifera leaf metabolites was done by GC-MS. Spherical nanoparticles having a size range of 57-144 nm were obtained with face-centered cubic crystals. The average crystallite size obtained from XRD spectra was 2.34 nm. Enhanced photocatalytic first-order kinetics were obtained for persistent organic pollutants, i.e., crystal violet, methylene blue, and malachite green (R2 = 0.99, 0.99, 0.98) in less than 15 min. Biomedical and agricultural significance as an antibiotic drug and utilization as a fungicides substitute was explored against nine resistant microbes. Statistically significant variations were analyzed via one-way analysis of variance (ANOVA) and Kruskal-Wallis test and specific multi comparison tests. Active to highly active inhibition zones manifested the use of biogenic silver nanoparticles as potential candidate for applications in biological arenas and as environmental remediators.


Asunto(s)
Contaminantes Ambientales , Nanopartículas del Metal , Prunus domestica , Antibacterianos , Biomimética , Tecnología Química Verde , Extractos Vegetales , Plata , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
5.
Environ Technol ; 40(28): 3745-3761, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29897295

RESUMEN

The present study has for the first time reported Prunus cerasifera leaf extract-mediated zinc oxide nanoparticles (ZnO NPs) in a green and one-pot synthetic mode without utilization of any chemical reducing agents. Synthesized nanoparticles were analysed by ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). UV-Vis peak was detected at 380 nm due to surface plasmon resonance. A variety of biomolecules were revealed by FTIR involved in reduction cum stabilization of ZnO NPs. Wurtzite hexagonal geometry with an average crystallite size of 12 nm was obtained from XRD diffraction pattern. SEM exhibited size ranges of 80-100 nm and 60-100 nm for 200°C and 600°C calcination temperatures. Synthesized nanoparticles were used as bio-cleaning photocatalysts against organic pollutants, i.e. bromocresol green, bromophenol blue, methyl red and methyl blue, which yielded pseudo-first-order reaction kinetics (R2 = 0.98, 0.92, 0.92 and 0.90, respectively). Pollutants expressed higher degradation percentages in less than 14 min in direct solar irradiance. Moreover, synthesized nanoparticles were tested against resistant microbes, i.e. Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Aspergillus terreus, Penicillium chrysogenum, Fusarium solani, Lasiodiplodia theobromae, Xanthomonas axonopodis pv. citri and Psuedomonas syringae for the development of a new generation of antimicrobial agents.


Asunto(s)
Contaminantes Ambientales , Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Antibacterianos , Extractos Vegetales , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
6.
Artif Cells Nanomed Biotechnol ; 46(sup1): 127-137, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29228870

RESUMEN

The present study has demystified the first and single step prunosynthesis of the spherical silver nanoparticles (AgNPs) from aqueous fruit extract of angiospermic plant, Prunus cerasifera, which has remarkable fusion of reducing cum stabilizing bioactive components (phenols, anthocyanins, carotenoids, flavonoids, organic acids, tannins and vitamins). Highly stable prunosynthetic AgNPs with 2.04 nm average crystallite size were synthesized in dark and in sunlight at optimized condition of temperature, time and P. cerasifera concentration. Synthesized nanoparticles were characterized through UV-Vis, FTIR, XRD, TGA, SEM and GCMS. Photocatalytic activity of prunosynthetic AgNPs was evaluated for methyl red, erichrome black, methyl blue, bromophenol blue and bromocresol green via UV-Vis. Degradation was achieved (<15 minutes) and expressed as pseudo-first-order kinetics. Prunosynthetic AgNPs demonstrated broad spectrum dose-dependent inhibition (in vitro) in comparison to standard antimicrobial drugs against pathogenic strains X. citri, P. syringae, A. niger, A. flavus, A. fumigatus, A. terreus, P. chrysogenum, F. solani and L. theobromae. Photocatalytic degradation results show the nanobioremediation potential of prunosynthetic AgNPs in indemnifying the persistent environmental pollutants. From the inherently higher inhibition rates for biomimetic prunosynthetic AgNPs, it is envisioned that these can be commercialized as future "green" nanobactericide and nanofungicide at industrial scale economically from nontoxic phytoconstituents.


Asunto(s)
Nanopartículas del Metal/química , Procesos Fotoquímicos , Extractos Vegetales/química , Prunus/química , Plata/química , Plata/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Catálisis , Técnicas de Química Sintética , Frutas/química , Agua/química
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