Montmorillonite Clay Catalysts Research Articles

Catalytic Pyrolysis of a Model Plastic Mixture with a Montmorillonite Clay Catalyst and Upgrading via Distillation

Catalytic Pyrolysis of a Model Plastic Mixture with a Montmorillonite Clay Catalyst and Upgrading via Distillation

Chemical upcycling of waste polyolefinic plastics to low-carbon synthetic naphtha for closing the plastic use loop

Designing an effective pathway to remove waste plastics from landfill and incineration plants and create a circular economy requires a more appropriate technology beyond the conventional mechanical recycling by melting and re-molding. This study aims to convert waste plastic into low-carbon synthetic naphtha which can be used as a feedstock for new plastic production, via a new and simple technical approach. To be specific, waste plastics are decomposed and reformed into naphtha fractions via a one-step catalytic pyrolysis over Al2O3 pillared montmorillonite clay catalyst. Experimental results show that Al2O3 pillared montmorillonite clay produces up to 60.3% C5-C12 alkanes, while ZSM-5 gives high contents of aromatics (46%) and olefins (35%). The promising results of Al2O3 pillared M-clay may be due to the special features of this material, including the large pore size and Al2O3-induced active sites (more Brønsted acid sites). The further batch experiments confirm the feasibility of scaling up and processing the polyolefinic plastic mixture.

A practical approach for synthesis of biodiesel via non-edible seeds oils using trimetallic based montmorillonite nano-catalyst

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.

Synthesis and Characterization of Waste Eggshell-Based Montmorillonite Clay Catalyst for Biodiesel Production from Waste Cooking Oil

The depletion of resources and increase in demand for fossil fuel raise concerns as it is natural and non-renewable. Therefore, it will cause limitation on its availability and continuous reduction. This issue has led to the search for more economic, sustainable, and environmentally friendly alternatives which is biodiesel. The major drawback that reduces the possibility of biodiesel commercialization is the high cost of oil feedstock as it covers 75% of its total production cost. The waste cooking oil is used as feedstock in continuous transesterification as it is the primary option to lower the cost of biodiesel production. Biodiesel can be prepared using waste cooking oil and catalyst through transesterification reaction. In this research, the focus is on the utilization of chicken and quail waste eggshell to synthesize highly active Calcium Oxide (CaO)-based heterogenous catalyst with montmorillonite clay to catalyze efficient conversion of waste cooking oil to biodiesel. The formation of CaO/montmorillonite catalyst was confirmed based on the outputs from X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The physio-chemically characteristics of catalysts exhibited a BET surface area from the ranging from 9.2-9.5 m2/g and presence of around 87% of elemental calcium as constituent through XRF characterization. In addition to this, high-performance liquid chromatography (HPLC) analysis is used to determine the conversion of biodiesel using conventional and microwave heating method which revealed a maximum biodiesel production yield of 98%. This optimum biodiesel yield was obtained at reaction temperature, molar ratio of waste cooking oil to methanol, and catalyst amount of 60 ºC, 2 h, 1:12, 2.5 wt.% and 5 wt.% for both eggshells, respectively.

A Sustainable Palladium-Intercalated Montmorillonite Clay Catalytic System for Imine Hydrogenation under Mild Conditions.

A series of palladium nanoparticles (Pd NPs) intercalated montmorillonite clay catalysts is reported for hydrogenation of 3-diphenyl prop-2-en-1-imine under mild reaction conditions. Pd/clay catalyst was prepared by a simple wet-impregnation method, and the physicochemical properties were characterized extensively by various techniques including N2 adsorption, XRD, TEM, XPS and TPR etc., which showed the intercalation of active Pd NPs between the clay layers. The effect of reaction conditions such as catalyst loading, reaction time, temperature and H2 pressure is explored, and thereby a plausible mechanism is proposed. The optimum amount of 6 wt % Pd/clay catalyst showed significant catalytic activity to yield 3-phenyl propyl aniline with 100 % conversion and selectivity under 5 bar pressure and a shorter reaction period of 3.5 h at 100 °C. The developed catalytic system unveiled excellent reusability over five cycles and hence paved the way for industrial applications.

Direct Synthesis and Characterization of Photo-Crosslinkable Biodegradable PLA-PEG-PLA Ttiblock Copolymer with Methacrylates Functions by Green Montmorillonite Clay Catalyst

Di-methacrylated PLA-PEG-PLA triblock copolymers of polylactide and polyethylene glycol were synthesized in one-step process by bulk cationic polymerization of lactide in the presence of PEG with different average molecular weights, using Maghnite-H+, an acidic montmorillonite clay, as a solid non-toxic catalyst. The obtained di-methacrylated copolymer was analyzed by 1H NMR and DSC. The effect of Maghnite-H+ proportions and PEG average molecular weight on the copolymerization and methacrylation yields and on average molecular weight of the resulting copolymers was studied.

Production of high quality biodiesel from novel non-edible Raphnus raphanistrum L. seed oil using copper modified montmorillonite clay catalyst

This study focused on producing high quality and yield of biodiesel from novel non-edible seed oil of abundantly available wild Raphnus raphanistrum L. using an efficient, recyclable and eco-friendly copper modified montmorillonite (MMT) clay catalyst. The maximum biodiesel yield of 83% was obtained by base catalyzed transesterification process under optimum operating conditions of methanol to oil ratio of 15:1, reaction temperature of 150 °C, reaction time of 5 h and catalyst loading of 3.5%. The synthesized catalyst and biodiesel were characterized for their structural features and chemical compositions using various state-of-the-art techniques, including x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H, 13C) and gas chromatography-mass spectroscopy. The fuel properties of the biodiesel were estimated including kinematic viscosity (4.36 cSt), density (0.8312 kg/L), flash point (72 °C), acid value (0.172 mgKOH/g) and sulphur content (0.0002 wt.%). These properties were compared and found in good agreement with the International Biodiesel Standards of American (ASTM-951, 6751), European Committee (EN-14214) and China GB/T 20828 (2007). The catalyst was re-used in five consecutive transesterification reactions without losing much catalytic efficiency. Overall, non-edible Raphnus raphanistrum L.. seed oil and Cu doped MMT clay catalyst appeared to be highly active, stable, and cheap contenders for future biofuel industry. However, detailed life cycle assessment (LCA) studies of Raphnus raphanistrum L. seed oil biodiesel are highly recommended to assess the technical, ecological, social and economic challenges.

Implication, visualization, and characterization through scanning electron microscopy as a tool to identify nonedible oil seeds.

Second-generation biofuels prove to be a distinctive and renewable source of sustainable energy and cleaner environment. The current study focuses on the exploration and identification of four nonedible sources, that is, Brassica oleracea L., Carthamus oxyacantha M.Bieb., Carthamus tinctorius L., and Beaumontia grandiflora Wall., utilizing light microscopy (LM) and scanning electron microscopy (SEM) for studying the detailed micromorphological features of these seeds. LM revealed that size ranges from 3 to 20 mm. furthermore, a great variety of color is observed from pitch black to greenish gray and yellowish white to off white. Seeds ultrastructure study with the help of SEM revealed a great variety in shape, size, color, sculpturing and periclinal wall shape, and so on. Followed by the production of fatty acid methyl esters from a novel source, that is, seeds oil of Brassica oleracea L. (seed oil content 42.20%, FFA content 0.329 mg KOH/g) using triple metal impregnated montmorillonite clay catalyst (Cu-Mg-Zn-Mmt). Catalyst was characterized using SEM-EDX, FT-IR. Maximum yield of Brassica oleracea L. biodiesel (87%) was obtained at the conditions; 1:9 of oil to methanol ratio, 0.5 g of catalyst, 5 hr reaction time, and 90°C of temperature. Synthesized biodiesel was characterized by FT-IR, GC-MS, and NMR. Fuel properties of the Brassica oleracea L. FAMES were determined and found in accordance with ASTM standards.

Efficacy of clay catalysts for the dehydration of fructose to 5-hydroxymethyl furfural in biphasic medium

5-Hydroxymethyl furfural (HMF) is one of the important platform chemical obtained from C6 sugars derived from biomass. The efficiency of montmorillonite clay catalysts (K-10, K-20, K-30, and Al pillared clay) has been systematically explored for the synthesis of HMF through dehydration of fructose in a biphasic solvent system. The catalysts were characterized by XRD, N2 sorption, 27Al MAS NMR, 29Si NMR and FT-IR of chemisorbed pyridine. Acid treated K-10 catalyst was found to be the best among the clay catalysts tested. Various reaction parameters such as reaction temperature, catalyst content, solvent were optimized for achieving better yield of HMF. Under optimized reaction conditions, K-10 catalyst affords 80 mol% fructose conversion with HMF yield of 61 mol%. Insight into the type of acid sites essential for such cascade reactions has been furnished. Utilization of clay catalysts for HMF production will be beneficial to improve overall economics for the production of platform chemicals like HMF from biomass-derived raw materials.

Optimization of novel Lepidium perfoliatum Linn. Biodiesel using zirconium-modified montmorillonite clay catalyst

ABSTRACT This work reports the potential of novel non-edible seed oil of Lepidium perfoliatum Linn. (LSO) for accessing its potential to synthesize biodiesel using zirconium-modified montmorillonite clay catalyst. The newly synthesized zirconium-modified clay catalyst (ZrO-Mmt) was characterized using by X-ray Powder Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray Spectroscopy (EDX), and Fourier transfer Infrared spectroscopy (FT-IR) spectroscopy. Response surface methodology (RSM) was used to optimize the Lepidium biodiesel (LBD) yield. Maximum biodiesel yield (88%) achieved under optimized reaction conditions were 1:15 oil: methanol, 3.5% catalyst amount at135°C for 4h respectively. Different techniques like FTIR, GC/MS, 1H-NMR, and 13C-NMR were used for characterizing LBD. Additionally, major fuel properties of LBD for instance kinematic viscosity (4.10 mm2/s), density (0.8212kg/L), cloud point (−8 °C), flash point (74°C), and pour point (−9°C) agree well with the international biodiesel standards. Overall, Lepidium perfoliatum Linn. seed oil and ZrO-Mmt clay catalysts appear to be cheap, stable, and highly active contenders for the biodiesel industry.

K-10 montmorillonite: An efficient and reusable catalyst for selective oxidation of aldehydes in the presence of dioxygen

A commercial montmorillonite clay catalyst, K-10 montmorillonite, was tested for catalytic oxidation of aldehydes in the presence of molecular oxygen under mild conditions. K-10 montmorillonite catalysed the oxidation of aldehydes with good activity and excellent selectivity toward the formation of the corresponding acids. The effects of the amount of catalyst, temperature and solvent on the catalytic activity were investigated. Remarkably, this catalyst was reusable without any appreciable loss in activity and selectivity.

Sustainable production of bioenergy from novel non-edible seed oil (Prunus cerasoides) using bimetallic impregnated montmorillonite clay catalyst

The current study examines the efficiency of double metals (Cd and Mn) impregnated montmorillonite clay (Cd-Mn-Mmt) catalyst for the cleaner synthesis of biodiesel from novel non-edible seed oil of Prunus Cerasoides D. Don. (seed oil content 54.5%, and FFA content 0.45 mg KOH/g). X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDX) and Fourier Transform Infrared Radiation Spectroscopy (FTIR) were used for characterizing the newly synthesized catalyst. The highest (85%) fatty acid methyl ester yield (FAME) of Prunus Cerasoides D. Don. biodiesel was obtained at optimized transesterification reaction conditions; 5 h of reaction time at 120 °C, 12:1 M ratio of methanol to oil and 4% catalyst loading. Synthesized biodiesel was further characterized via FTIR, Gas Chromatography/Mass spectroscopy (GC/MS), and Nuclear magnetic resonance (NMR (1H, 13C)). Additionally, the determined fuel properties, such as density (0.8612 kg/L), kinematic viscosity (4.11 mm2/s), flash point (73 °C), cloud point (−9 °C) and pour point (−10 °C), of synthesized biodiesel, agreed with International Standards of China GB/T 20828 (2007), American (ASTM-951, 6751) and European Union (EU-14214). Pseudo-first-order kinetics fitted well with the experimental data (R2 = 0.9172). The study findings recommended that the modified montmorillonite clay catalyst is a cleaner, cheaper, and easy to use along with high stability and catalytic performance in the transesterification process.

An efficient and robust heterogeneous mesoporous montmorillonite clay catalyst for the Biginelli type reactions

Three component coupling reactions of aldehyde, β-ketoester (or β-diketone) and urea (or substituted urea) were carried out by using acid activated montmorillonite clay (AT-Mont.) catalyst having surface area about 400m2/g for the facile synthesis of 3,4-dihydropyrimidin-2(1H)-ones via the Biginelli reactions under mild reaction conditions. The activation of montmorillonite clay was carried out with HCl under controlled conditions for generating nanopores (size 2–7nm) into the matrix. This porous catalyst has promising feature for Biginelli reaction such as easy removal of the catalyst, short reaction time, high yield with 100% selectivity and easy workup procedure. Powder XRD, SEM-EDX, N2 adsorption, pyridine adsorbed FT-IR and TPD analysis were carried out to characterize the solid porous AT-Mont. The catalysts can be recycled and reused several times without significant loss of their catalytic activity.

Nucleotide Selectivity in Abiotic RNA Polymerization Reactions

In order to establish an RNA world on early Earth, the nucleotides must form polymers through chemical rather than biochemical reactions. The polymerization products must be long enough to perform catalytic functions, including self-replication, and to preserve genetic information. These functions depend not only on the length of the polymers, but also on their sequences. To date, studies of abiotic RNA polymerization generally have focused on routes to polymerization of a single nucleotide and lengths of the homopolymer products. Less work has been done the selectivity of the reaction toward incorporation of some nucleotides over others in nucleotide mixtures. Such information is an essential step toward understanding the chemical evolution of RNA. To address this question, in the present work RNA polymerization reactions were performed in the presence of montmorillonite clay catalyst. The nucleotides included the monophosphates of adenosine, cytosine, guanosine, uridine and inosine. Experiments included reactions of mixtures of an imidazole-activated nucleotide (ImpX) with one or more unactivated nucleotides (XMP), of two or more ImpX, and of XMP that were activated in situ in the polymerization reaction itself. The reaction products were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify the lengths and nucleotide compositions of the polymerization products. The results show that the extent of polymerization, the degree of heteropolymerization vs. homopolymerization, and the composition of the polymeric products all vary among the different nucleotides and depend upon which nucleotides and how many different nucleotides are present in the mixture.

Solvent free one pot synthesis of amidoalkyl naphthols over phosphotungstic acid encapsulated montmorillonite clay catalysts

Montmorillonite KSF clay was effectively modified by the encapsulation of phosphotungstic acid into the clay layers via sonication followed by incipient wet impregnation method. The prepared catalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The catalytic activities of the prepared systems were investigated in the solvent free synthesis of amidoalkyl naphthols by the multicomponent one-pot condensation of an aldehyde, β-naphthol and an amide or urea. Excellent yield, shorter reaction time, easy work-up, and reusability of the catalyst are the main attractions of this green procedure.

In situ imidazole activation of ribonucleotides for abiotic RNA oligomerization reactions.

The hypothesis that RNA played a significant role in the origin of life requires effective and efficient abiotic pathways to produce RNA oligomers. The most successful abiotic oligomerization reactions to date have utilized high-energy, modified, or pre-activated ribonucleotides to generate strands of RNA up to 50-mers in length. In spite of their success, these modifications and pre-activation reactions significantly alter the ribonucleotides in ways that are highly unlikely to have occurred on a prebiotic Earth. This research seeks to address this problem by exploring an aqueous based method for activating the canonical ribonucleotides in situ using 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and imidazole. The reactions were run with and without a montmorillonite clay catalyst and compared to reactions that used ribonucleotides that were pre-activated with imidazole. The effects of pH and ribonucleotide concentration were also investigated. The results demonstrate the ability of in situ activation of ribonucleotides to generate linear RNA oligomers in solution, providing an alternative route to produce RNA for use in prebiotic Earth scenarios.

Cationic Ring Opening polymerization of ε-caprolactam by a Montmorillonite Clay Catalyst

The ring opening bulk polymerization of ε-caprolactam catalyzed by Maghnite-H+ was reported. Maghnite-H+ is a montmorillonite silicate sheet clay was prepared through a straight forward proton exchange process. The effect of the amount of catalyst, and temperature was studied. Increasing Maghnite-H+ proportion and temperature produced the increase in ε-caprolactam conversion. The kinetics indicated that the polymerization rate is first order with respect to monomer concentration. Mechanism studies showed that monomer inserted into the growing chains with the acyl–oxygen bond scission rather than the break of alkyl–oxygen bond. © 2014 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)

K-10 montmorillonite: An efficient and reusable catalyst for the aerobic C[sbnd]C bond cleavage of α-substituted ketones

A commercially available acid-activated montmorillonite clay catalyst, K10 montmorillonite, was tested for the catalytic oxidation of cyclic ketones in the presence of molecular oxygen under mild conditions (343K and atmospheric pressure). K10 montmorillonite catalyzed the oxidative cleavage of CC bonds in 2-methylcyclohexanone, 2-phenylcyclohexanone, 2-hydroxylcyclohexanone and 1,2-cyclohexanedione with good activity and excellent selectivity toward the formation of the corresponding ketoacids and diacids. The effects of acidity, amount of catalyst, temperature and solvent on the catalytic activity were investigated. Furthermore, this catalyst was reusable without any appreciable loss in activity and selectivity.

A first one-pot synthesis, isomerization and synthetic utility of mono- and bis Morita–Baylis–Hillman adducts of 1,1′-ferrocenedialdehyde

A one-pot synthesis of mono- and bis-Morita–Baylis–Hillman adducts of 1,1′-ferrocenedialdehyde has been achieved. These adducts undergo a facile and efficient stereoselective isomerization with a number of saturated, unsaturated, aromatic alcohols, phenols and thiophenol with a montmorillonite K10 clay catalyst to afford highly functionalized trisubstituted alkene derivatives of ferrocene. The synthetic utility of isomerized derivatives has been demonstrated by a ferrocene appended novel macrocycle synthesis, a ferrocenyl bis-triazole synthesis and an evaluation of the liquid crystalline property of a cholesterol derivative of ferrocene.

Brønsted and Lewis acidity of modified montmorillonite clay catalysts determined by FT-IR spectroscopy

The surface acidity of different modified montmorillonite clay catalysts, Al 3+-exchanged montmorillonite (Al 3+-Mont) and aluminium pillared montmorillonite (Al-PILC) was determined by DRIFTS (diffuse reflectance Fourier transform infrared spectra) using pyridine as probe molecule. The method involved treating the clay sample directly with pyridine, drying the sample at 120 °C and recording FT-IR spectra in the region 1650 and 1350 cm −1. The spectra obtained showed well resolved absorption bands for Lewis and Brønsted acid sites in the clay catalysts. In order to understand the role of acid sites present on clay catalysts, esterification of propionic acid with p-cresol has been studied. The Brønsted acidity data obtained by FT-IR study for modified montmorillonite clay catalysts correlated well with the catalytic activity in the esterification reaction. Among the modified clay catalysts, Al 3+-Mont and H +-Mont clay catalysts showed good activity and Al-PILC showed negligible activity in esterification. The inactivity of Al-PILC catalysts is attributed to the absence of Brønsted acidity.