The one-pot conversion of furfuryl alcohol (FA) into GVL was investigated over the sol-gel-synthesized AlO-SiO (AlSi) catalysts with various AlO loadings (0.2-10 wt %) and commercial zeolites including MFI-1, H-ZSM5, H-beta, and HY-15 in a batch reactor under mild reaction conditions (130 °C, 1 bar N, and 15-120 min). The reaction pathways depend largely on the acid properties of the catalysts, especially the types of Bronsted (B) and Lewis (L) acid sites.
View Article and Find Full Text PDFThis work aimed to study the deoxygenation of two different waste cooking oils (WCOs; palm oil and soybean oil) using alumina (γ-AlO)-supported and unsupported NiMoS catalysts prepared by the hydrothermal method. The variables evaluated in this study were the reactant concentration, reaction time, and nickel (Ni)/[Ni + molybdenum (Mo)] atomic ratio (0.2 and 0.
View Article and Find Full Text PDFMolecules
August 2023
(-)-Epigallocatechin gallate (EGCG) is a bioactive component of green tea that provides many health benefits. However, excessive intake of green tea may cause adverse effects of caffeine (CAF) since green tea (30-50 mg) has half the CAF content of coffee (80-100 mg). In this work, for enhancing the health benefits of green tea, natural rubber/hexagonal mesoporous silica (NR/HMS) nanocomposites with tunable textural properties were synthesized using different amine template sizes and applied as selective adsorbents to separate EGCG and CAF from green tea.
View Article and Find Full Text PDFThis study is the first report on the synthesis, characterization and application of amine-functionalized mesoporous nanocomposites based on natural rubber (NR) and wormhole-like mesostructured silica (WMS). In comparison with amine-functionalized WMS (WMS-NH), a series of NR/WMS-NH composites were synthesized via an in situ sol-gel method in which the organo-amine group was grafted onto the nanocomposite surface via co-condensation with 3-aminopropyltrimethoxysilane (APS) as the amine-functional group precursor. The NR/WMS-NH materials had a high specific surface area (115-492 m g) and total pore volume (0.
View Article and Find Full Text PDFThe by-product of the previous transesterification, glycerol was utilised as an acid catalyst precursor for biodiesel production. The crude glycerol was treated through the sulfonation method with sulfuric acid and chlorosulfonic acid in a reflux batch reactor giving solid glycerol-SOH and glycerol-ClSOH, respectively. The synthesised acidic glycerol catalysts were characterised by various analytical techniques such as thermalgravimetric analyser (TGA), infrared spectroscopy, surface properties adsorption-desorption by nitrogen gas, ammonia-temperature programmed desorption (NH-TPD), X-ray diffraction spectroscopy (XRD), elemental composition analysis by energy dispersive spectrometer (EDX) and surface micrographic morphologies by field emission electron microscope (FESEM).
View Article and Find Full Text PDFNearly 15 billion metric tons of fossil fuels are consumed each year all over the world resulting in the depletion of non-renewable energy resources day by day therefore in the coming years, the shortage and price hikes of these fuels are inevitable. On the other hand, the global energy demand is projected to rise by almost 28% by 2040 compared to current levels. Thus, there is a dire need for developing the alternatives to meet these energy needs.
View Article and Find Full Text PDFSci Total Environ
August 2022
Cancer is one of the most deadly diseases on the planet. Over the past decades, numerous antineoplastic compounds have been discovered from natural resources such as medicinal plants and marine species as part of multiple drug discovery initiatives. Notably, several marine flora (e.
View Article and Find Full Text PDFThe macroalgal industry is expanding, and the quest for novel ingredients to improve and develop innovative products is crucial. Consumers are increasingly looking for natural-derived ingredients in cosmetic products that have been proven to be effective and safe. Macroalgae-derived compounds have growing popularity in skincare products as they are natural, abundant, biocompatible, and renewable.
View Article and Find Full Text PDFOrganosulfonic acid-functionalized mesoporous silica is a class of heterogeneous acid catalysts used in esterification processes due to its high surface area, shape-selective properties, and strongly acidic sites. Since water is generated as a by-product of esterification, the surface of mesostructured silica is modified to enhance hydrophobicity and catalytic performance. In this study, a series of propylsulfonic acid-functionalized nanocomposites based on natural rubber and hexagonal mesoporous silica (NRHMS-SOH) with different acidities were prepared via an in situ sol-gel process using tetraethyl orthosilicate as the silica source, dodecylamine as the nonionic templating agent, and (3-mercaptopropyl)trimethoxysilane as the acid-functional group precursor.
View Article and Find Full Text PDFGlycerol is a byproduct from biodiesel production via conventional transesterification processes, representing approximately 10 wt% of the mass of biodiesel produced. Because of increasing biodiesel consumption, the volume of glycerol being produced has grown significantly, leading to a large surplus and, consequently, a dramatic drop in its market value. Thus, the valorization of glycerol into chemicals is a promising pathway toward sustainability in biodiesel industries.
View Article and Find Full Text PDFUsage of plastics in the form of personal protective equipment, medical devices, and common packages has increased alarmingly during these pandemic times. Though they have served as an excellent protection source in minimizing the coronavirus disease (COVID-19) spreading, they have still emerged as major environmental pollutants nowadays. These non-degradable COVID-19 plastic wastes (CPW) were treated through incineration and landfilling process, which may lead to either the release of harmful gases or contaminating the surrounding environment.
View Article and Find Full Text PDFLignocellulosic biomass is a highly renewable, economical, and carbon-neutral feedstock containing sugar-rich moieties that can be processed to produce second-generation biofuels and bio-sourced compounds. However, due to their heterogeneous multi-scale structure, the lignocellulosic materials have major limitations to valorization and exhibit recalcitrance to saccharification or hydrolysis by enzymes. In this context, this review focuses on the latest methods available and state-of-the-art technologies in the pretreatment of lignocellulosic biomass, which aids the disintegration of the complex materials into monomeric units.
View Article and Find Full Text PDFJ Hazard Mater
January 2022
Industrial and textile dyes are the major source of water pollutants in the Coimbatore Districts of Tamil Nadu, India. The highly stable organic dyes from these industries are being discharged untreated into neighboring rivers, lakes, and ponds. Thus, the present study mainly focused on the preparation of bimetallic nanocomposite (Ag-Sn) through Free-facile Teflon autoclave methodology and their subsequent stimulation has given to the photocatalyst by visible light irradiation.
View Article and Find Full Text PDFCOVID-19 has led to the enormous rise of medical wastes throughout the world, and these have mainly been generated from hospitals, clinics, and other healthcare establishments. This creates an additional challenge in medical waste management, particularly in developing countries. Improper managing of medical waste may have serious public health issues and a significant impact on the environment.
View Article and Find Full Text PDFRecently, the COVID-19 disease spread has emerged as a worldwide pandemic and cause severe threats to humanity. The World Health Organisation (WHO) releases guidelines to help the countries to reduce the spread of this virus to the public, like wearing masks, hand hygiene, social distancing, shutting down all types of public transports, etc. These conditions led to a worldwide economic fall drastically, and on the other hand, indirect environmental benefits like global air quality improvement and decreased water pollution are also pictured.
View Article and Find Full Text PDFEnviron Technol Innov
November 2020
Coronavirus 2019 (COVID-19) has globally affected the human mortality rate and economic history of the modern world. According to the World Health Organization, COVID-19 has caused a severe threat to the health of the vulnerable groups, notably the elderly. There is still some disagreements regarding the source of the virus and its intermediate host.
View Article and Find Full Text PDFThis study is the first report on the preparation of mesoporous carbon/silica (MCS) nanocomposites with tunable mesoporosity and hydrophobicity using natural rubber (NR) as a renewable and cheap carbon source. A series of mesoporous nanocomposites based on NR and hexagonal mesoporous silica (HMS) were prepared via an in situ sol-gel process and used as precursors; then, they were converted into MCS materials by controlled carbonization. The NR/HMS precursors exhibited a high dispersion of rubber phase incorporated into the mesostructured silica framework as confirmed by small-angle X-ray scattering and high-resolution transmission electron microscopy.
View Article and Find Full Text PDFThe potential of bifunctional nanocatalysts obtained from waste palm kernel shell (PKS) was investigated for one-step transesterification-esterification under mild conditions. State-of-the-art characterization illustrated that the synthesized catalyst has high stability through the thermal test, high BET surface area of 438.08 m g, pore volume of 0.
View Article and Find Full Text PDFThe main purpose of this work is to investigate the application options of the char produced from gasification plants. Two promising mesoporous acidic catalysts were synthesized using char as a support material. Two char samples were collected from either a dual-stage or a rising co-current biomass gasification plant.
View Article and Find Full Text PDFNatural rubber (NR)/hexagonal mesoporous silica (HMS) nanocomposites (NRHMS) with enhanced thermal and hydrophobic properties were facilely prepared via in situ sol-gel formation with pH adjustment using a low sulphuric acid (HSO) acid concentration. The effect of the amount of 0.5 M HSO (2.
View Article and Find Full Text PDFAdsorption mechanisms and the role of different porous and crystalline structures on the removal of five haloacetonitriles (HANs) over hexagonal mesoporous silica (HMS), titanium substituted mesoporous silica (Ti-HMS), rod-shaped SBA-15 and microporous zeolite NaY were investigated. In addition, the effect of pH on adsorption mechanism and selective adsorption of five HANs individually and in an equimolar mixed solution were evaluated. The results indicated that the intraparticle diffusion rate constants of the mesoporous adsorbents were higher than that of the microporous NaY.
View Article and Find Full Text PDFThe selective adsorption mechanisms of naproxen (NAP), acetaminophen (ACT), and clofibric acid (CFA) on silica-based porous materials were examined by single and mixed-batch adsorption. Effects of the types and densities of surface functional groups on adsorption capacities were determined, including the role of hydrophobic and hydrophilic dissolved organic matters (DOMs). Hexagonal mesoporous silica (HMS), superparamagnetic HMS (HMS-SP) and SBA-15 were functionalized and applied as adsorbents.
View Article and Find Full Text PDFTo investigate the adsorption properties and mechanisms of haloacetonitriles (HANs), large-pore SBA-15 mesoporous silica (SBA-CHX) was synthesized using cyclohexane as a swelling agent, and the surface was modified with polymerizable gemini surfactant (PG). The structure and textural properties of the synthesized adsorbents were characterized. PG surfactant coverage on the surface and the degree of polymerization were confirmed with FT-IR analysis.
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