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1.
J Environ Manage ; 350: 119567, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38007927

RESUMO

Dealing with the current defaults of environmental toxicity, heating, waste management, and economic crises, exploration of novel non-edible, toxic, and waste feedstock for renewable biodiesel synthesis is the need of the hour. The present study is concerned with Buxus papillosa with seeds oil concentration (45% w/w), a promising biodiesel feedstock encountering environmental defaults and waste management; in addition, this research performed simulation based-response surface methodology (RSM) for Buxus papillosa bio-diesel. Synthesis and application of novel Phyto-nanocatalyst bimetallic oxide with Buxus papillosa fruit capsule aqueous extract was advantageous during transesterification. Characterization of sodium/potassium oxide Phyto-nanocatalyst confirmed 23.5 nm nano-size and enhanced catalytic activity. Other characterizing tools are FTIR, DRS, XRD, Zeta potential, SEM, and EDX. Methyl ester formation was authenticated by FTIR, GC-MS, and NMR. A maximum 97% yield was obtained at optimized conditions i.e., methanol ratio to oil (8:1), catalyst amount (0.37 wt%), reaction duration (180 min), and temperature of 80 °C. The reusability of novel sodium/potassium oxide was checked for six reactions. Buxus papillosa fuel properties were within the international restrictions of fuel. The sulphur content of 0.00090% signified the environmental remedial nature of Buxus papillosa methyl esters and it is a highly recommendable species for biodiesel production at large scale due to a t huge number of seeds production and vast distribution.


Assuntos
Buxus , Gerenciamento de Resíduos , Resíduos Perigosos , Biocombustíveis/análise , Ésteres , Catálise , Sódio , Óleos de Plantas
2.
Chemosphere ; 322: 138078, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36754302

RESUMO

Conventional homogeneous-based catalyzed transesterification for the production of biodiesel can be replaced with a membrane reactor that has an immobilized heterogeneous catalyst. Combining reaction with separation while utilizing membranes with a certain pore size might boost conversion process. this investigation to study the effectiveness of membrane reactor in combination with heterogeneous green nano catalysis of MnO2. Techniques such as XRD, EDX, FTIR, SEM, and TGA were used to characterize the synthesized MnO2 nano catalyst. The highest conversion of around 94% Trachyspermum ammi oil was obtained by MnO2. The optimum process variables for maximum conversion were catalyst loading of 0.26 (wt.%), 8:1 M ratio, 90 °C reaction temperature, and time 120 min. The green nano catalyst of MnO2 was reusable up to five cycles with minimum loss in conversion rate of about 75% in the fifth cycle. Nuclear magnetic resonance validated the synthesis of methyl esters. It was concluded that membrane reactor a promising technique to efficiently transesterify triglycerides into methyl esters and enable process intensification uses MnO2 as a catalyst.


Assuntos
Ammi , Óxidos , Compostos de Manganês , Biocombustíveis , Esterificação , Ésteres , Óleos de Plantas
3.
Chemosphere ; 322: 138184, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36812997

RESUMO

The purpose of this paper is to demonstrate the use of the phase separation procedure in order to synthesize ultrafiltration polycarbonate containing aluminum oxide (Al2O3) nanoparticles (NPs) to remove emerging contaminants from wastewater at varying temperatures and nanoparticle contents. In the membrane structure, Al2O3-NPs are loaded at rates of 0≤φ≤1% volume. Fourier transform infrared (FTIR), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were used to characterize the fabricated membrane containing Al2O3-NPs. Nevertheless, volume fractions ranged from 0 to 1% during the experiment, which was conducted between 15 and 55 °C. An analysis of the ultrafiltration results was conducted by using a curve-fitting model to determine the interaction between these parameters and the effect of all independent factors on the emerging containment removal. Shear stress and shear rate for this nanofluid are nonlinear at different temperatures and volume fractions. Viscosity decreases with increasing temperature at a specific volume fraction. In order to remove emerging contaminants, a decrease in viscosity at a relative level fluctuates, resulting in more porosity in the membrane. NPs become more viscous with an increasing volume fraction at any given temperature on the membrane. For example, a maximum relative viscosity increases of 34.97% is observed for a 1% volume fraction at 55 °C. A novel model is then used to measure the viscosity of nanofluid. This indicates that the results and experimental data are in very close agreement, as the maximum deviation is 2.6%.


Assuntos
Nanopartículas , Águas Residuárias , Temperatura , Nanopartículas/química , Óxido de Alumínio/química
4.
Chemosphere ; 309(Pt 1): 136622, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36181837

RESUMO

Lubricants operate as antifriction media, preserving machine reliability, facilitating smooth operation, and reducing the likelihood of frequent breakdowns. The petroleum-based reserves are decreasing globally, leading to price increases and raising concerns about environmental degradation. The researchers are concentrating their efforts on developing and commercializing an environmentally friendly lubricant produced from renewable resources. Biolubricants derived from nonedible vegetable oils are environmentally favorable because of their non-toxicity, biodegradability, and close to net zero greenhouse gas emissions. The demand for bio lubricants in industry and other sectors is increasing due to their non-toxic, renewable, and environmentally friendly nature. Good lubrication, anti-corrosion, and high flammability are characteristic properties of vegetable oils due to their unique structure. This study presents several key properties of nonedible oils that are used to produce lubricants via the transesterification process. Bibliometric analysis is also performed, which provides us with a better understanding of previous studies related to the production of bio lubricants from the transesterification process. Only 371 published documents in the Scopus database were found to relate to the production of bio lubricants using the transesterification process. The published work was mostly dominated by research articles (286; 77.088%). Significant development can be seen in recent years, with the highest occurrence in 2021, reaching 68 publications accounting for 18.38% of the total documents. In the second step, (i) the authors with the most number of publications; (ii) journals with the most productions; (iii) most productive countries; and (iv) the authors' most frequently used keywords were evaluated. These results will provide a pathway for researchers interested in this field. Lastly, recommendation is made on research gaps to device possible strategies for its commercialization.


Assuntos
Gases de Efeito Estufa , Petróleo , Reprodutibilidade dos Testes , Lubrificantes/química , Óleos de Plantas
5.
Environ Res ; 213: 113721, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35738420

RESUMO

This work presents the enhancement of oil biodegradation in seawater using a mixture of oil and microorganisms. Retardation of crude oil biodegradation in seawater is hypothetically due to the inhibiting of metabolites produced by the oil bacterium which inhibit its enzymes. For this purpose, the bacteria consortium consisting of an active oil-oxidizing bacterium (AR3-Pseudomonas pseudoalcaligenes) and two oil-resistant and active heterotrophic bacteria (OG1 and OG2-Erythrobacter citreus) were formed. The heterotrophic bacteria, OG1 and OG2 were able to remove metabolites produced during oil degradation. It was found that AR3 was retarded by metabolites, while OG1 and OG2 were able to grow in the metabolites. OG1 and OG2 were applied together to enhance growth and removal of the metabolites. About 59.9% of crude oil degradation was degraded by AR3 pure culture, while 68.6% was degraded by the bacteria consortium. About 31.4% of the crude oil was found to remain in seawater due to the presence of asphaltenes and resin hydrocarbons. The bacteria consortium was able to degrade 84.1% of total hydrocarbons while 67.0% was degraded by AR3. A total of 99.8% of the aliphatic content and 38.4% of the total aromatic hydrocarbons were degraded by the bacteria consortium, while a lower 79.4% of total aliphatic and 31.0% of total aromatic were degraded by AR3 under the same experimental conditions. The results which were obtained from this study support the hypothesis that the retardation of oil degradation by AR3 is due to the inhibition of metabolites on the growth.


Assuntos
Petróleo , Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos , Água do Mar
6.
Chemosphere ; 303(Pt 2): 135138, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35636597

RESUMO

Green nano-technology together with the availability of eco-friendly and alternative sources are the promising candidates to combat environment deteriorations and energy clutches globally. The current work focuses on the synthesis and application of newly synthesized nano catalyst of Iodine doped Potassium oxide I (K2O) for producing sustainable biodiesel from novel non-edible seed oils of Coronopus didymus L. using membrane based contactor to avoid emulsification and phase separation issues. Highest biodiesel yield (97.03%) was obtained under optimum conditions of 12:1 methanol to oil ratio, reaction temperature of 65 °C for 150 min with the 1.0 wt% catalyst concentration. The lately synthesized, environment friendly and recyclable Iodine doped Potassium oxide K (IO)2 catalyst was synthesized via chemical method followed by characterization via advanced techniques including EDX, XRD, FTIR and SEM analysis. The catalyst was proved to be stable and efficient with the reusability of five times in transesterification reaction. These analysis have reported the sustainability, stability and good quality of biodiesel from seed oil of Coronopus didymus L. using efficient Iodine doped potassium oxide catalyst. Thus, non-edible, environment friendly and novel Coronopus didymus L. seeds and their extracted oil along with Iodine doped potassium oxide catalyst seems to be highly affective, sustainable and better alternative source to the future biodiesel industry. Also, by altering the reaction equilibrium and lowering the purification phases of the process, these studies show the potential of coupling transesterification and a membrane contactor.


Assuntos
Biocombustíveis , Iodo , Biocombustíveis/análise , Catálise , Esterificação , Iodetos , Óxidos , Óleos de Plantas/química , Compostos de Potássio
7.
Bioresour Technol ; 343: 126068, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34626762

RESUMO

The efforts have been made to review phyllosilicate derived (clay-based) heterogeneous catalysts for biodiesel production via lignocellulose derived feedstocks. These catalysts have many practical and potential applications in green catalysis. Phyllosilicate derived heterogeneous catalysts (modified via any of these approaches like acid activated clays, ion exchanged clays and layered double hydroxides) exhibits excellent catalytic activity for producing cost effective and high yield biodiesel. The combination of different protocols (intercalated catalysts, ion exchanged catalysts, acidic activated clay catalysts, clay-supported catalysts, composites and hybrids, pillared interlayer clay catalysts, and hierarchically structured catalysts) was implemented so as to achieve the synergetic effects (acidic-basic) in resultant material (catalyst) for efficient conversion of lignocellulose derived feedstock (non-edible oils) to biodiesel. Utilisation of these Phyllosilicate derived catalysts will pave path for future researchers to investigate the cost-effective, accessible and improved approaches in synthesising novel catalysts that could be used for converting lignocellulosic biomass to eco-friendly biodiesel.


Assuntos
Biocombustíveis , Óleos de Plantas , Biomassa , Catálise , Esterificação , Lignina
8.
Chemosphere ; 291(Pt 2): 132780, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34767846

RESUMO

The present work investigates the proficiency of green silver oxide nanocatalyst synthesised from Monotheca buxifolia (Falc.) Dcne. leaves extract, and their application for biodiesel synthesis from novel Prunus bokhariensis seed oil (non-edible). The seed oil content of 55% and FFA content of 0.80 mg KOH/g were reported. Several analytical tools (EDX, FT-IR, SEM and XRD) were used to characterise the Ag2O nanocatalyst. Maximum (89%) FAME yield of the PBSOB (Prunus bokhariensis seed oil biodiesel) was achieved at ambient transesterification conditions i.e. 3.5 wt% nanocatalyst loading, 2.5 h reaction time, 130 °C of reaction temperature and 12:1 alcohol to oil ratio. The synthesised PBSOB was additionally characterised by analytical methods like, GC-MS and FT-IR. The different aspects of fuel were identified i.e. flash point (84 °C), kinematic viscosity (4.01 cSt @ 40 °C), sulphur content (0.0003 wt %), density (0.853 kg/L) and acid number (0.167 mg KOH/g). All the above properties were verified and agreed well with biodiesel international standards (European Union (14214), China GB/T (20828) and ASTM (6751, 951). In general, Prunus bokhariensis seed oil and Ag2O nanocatalyst seem to be remarkably active, cheap and stable candidates for the biodiesel industry in future.


Assuntos
Biocombustíveis , Prunus , Biocombustíveis/análise , Catálise , Esterificação , Óxidos , Óleos de Plantas , Compostos de Prata , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Chemosphere ; 278: 130469, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33839393

RESUMO

The present study defines a novel green method for the synthesis of the nickel oxide nanocatalyst by using an aqueous latex extract of the Ficus elastic. The catalyst was examined for the conversion of novel Brachychiton populneus seed oil (BPSO) into biodiesel. The Brachychiton populneus seeds have a higher oil content (41 wt%) and free fatty acid value (3.8 mg KOH/g). The synthesised green nanocatalyst was examined by the Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-Ray (EDX) spectroscopy, X-Ray diffraction (XRD) spectroscopy and scanning electron microscopy (SEM). The obtained results show that the synthesised green nanocatalyst was 22-26 nm in diameter and spherical-cubic in shape with a higher rate of catalytic efficiency. It was utilised further for the conversion of BPSO into biofuel. Due to the high free fatty acid value, the biodiesel was synthesised by the two-step process, i.e., pretreatment of the BPSO by means of acid esterification and then followed by the transesterification reaction. The acidic catalyst (H2SO4) was used for the pretreatment of BPSO. The optimum condition for the transesterification of the pretreated BPSO was 1:9 of oil-methanol molar ratio, 2.5 wt % of prepared nanocatalyst concentration and 85 °C of reaction temperature corresponding to the highest biodiesel yield of 97.5 wt%. The synthesised biodiesel was analysed by the FT-IR and GC-MS technique to determine the chemical composition of fatty acid methyl esters. Fuel properties of Brachychiton populneus seed oil biodiesel (BPSOB) were also examined, compared, and it falls in the prescribed range of ASTM standards.


Assuntos
Biocombustíveis , Óleos de Plantas , Biocombustíveis/análise , Catálise , Esterificação , Níquel , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Bioresour Technol ; 328: 124859, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33621759

RESUMO

The potential of new trimetallic (Ce, Cu, La) loaded montmorillonite clay catalyst for synthesizing biodiesel using novel non-edible Celastrus paniculatus Willd seed oil via two-step transesterification reaction has been reported along with catalyst characterization. Transesterification reaction was optimized and maximum biodiesel yield of 89.42% achieved under optimal operating reaction states like; 1:12 oil to methanol ratio, 3.5% of catalyst amount, 120 °C of reaction temperature for 3 h. The predicted and experimental biodiesel yields under these reaction conditions were 89.42 and 89.40%, which showing less than 0.05% variation. Additionally, optimum biodiesel yield can be predicted by drawing 3D surface plots and 2D contour plots using MINITAB 17 software. For the characterization of the obtained biodiesel, analysis including the GC/MS, FT-IR, 1H NMR and 13C NMR were applied. The fuel properties of obtained biodiesel agrees well with the different European Union (EU-14214), China (GB/T 20828), and American (ASTM-951, 6751) standards.


Assuntos
Bentonita , Biocombustíveis , Biocombustíveis/análise , Catálise , China , Esterificação , Óleos de Plantas/análise , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Bioresour Technol ; 242: 272-282, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28341378

RESUMO

Chemical interesterification of rubber seed oil has been investigated for four different designed orifice devices in a pilot scale hydrodynamic cavitation (HC) system. Upstream pressure within 1-3.5bar induced cavities to intensify the process. An optimal orifice plate geometry was considered as plate with 1mm dia hole having 21 holes at 3bar inlet pressure. The optimisation results of interesterification were revealed by response surface methodology; methyl acetate to oil molar ratio of 14:1, catalyst amount of 0.75wt.% and reaction time of 20min at 50°C. HC is compared to mechanical stirring (MS) at optimised values. The reaction rate constant and the frequency factor of HC were 3.4-fold shorter and 3.2-fold higher than MS. The interesterified product was characterised by following EN 14214 and ASTM D 6751 international standards.


Assuntos
Hevea , Óleos de Plantas , Catálise , Hidrodinâmica , Borracha , Sementes
12.
Bioresour Technol ; 199: 414-422, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26298387

RESUMO

Pretreatment of the high free fatty acid rubber seed oil (RSO) via esterification reaction has been investigated by using a pilot scale hydrodynamic cavitation (HC) reactor. Four newly designed orifice plate geometries are studied. Cavities are induced by assisted double diaphragm pump in the range of 1-3.5 bar inlet pressure. An optimised plate with 21 holes of 1mm diameter and inlet pressure of 3 bar resulted in RSO acid value reduction from 72.36 to 2.64 mg KOH/g within 30 min of reaction time. Reaction parameters have been optimised by using response surface methodology and found as methanol to oil ratio of 6:1, catalyst concentration of 8 wt%, reaction time of 30 min and reaction temperature of 55°C. The reaction time and esterified efficiency of HC was three fold shorter and four fold higher than mechanical stirring. This makes the HC process more environmental friendly.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Hevea/química , Óleos de Plantas/química , Biotecnologia/instrumentação , Catálise , Desenho de Equipamento , Esterificação , Ácidos Graxos não Esterificados/química , Hidrodinâmica , Metanol/química , Pressão , Sementes/química , Temperatura
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