Coeficientes del modelo de regresión logística binomial (aprendizaje)

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Synthesis of Ti(SO4)O solid acid nano-catalyst and its application for biodiesel production from used cooking oil

Synthesis of Ti(SO4)O solid acid nano-catalyst and its application for biodiesel production from used cooking oil

and transesterification of free fatty acids in used cooking oil (UCO) to produce biodiesel. The synthesised nano-catalyst was fully characterised by different analytical techniques. The XPS results clearly confirmed that the bidentate sulphate coordinated to the Ti 4+ metal in the nano-catalyst product. Obtained d-spacing values from the experimental data of XRD peaks and the SAED pattern of produced nano-catalyst agreed well with the d-spacing values from the JCPDS-ICDD card numbers 04-011-4951 for titanium sulphate oxide or titanium oxysulfate crystal structures.This confirms the sulphate groups were within the crystalline structure rather than on the surface of titania nano particles, which has not been previously reported. It has been demonstrated 97.1% yield for the fatty acid methyl ester can be achieved usign the synthetised catalyst under a reaction time of 3 hrs, catalyst to UCO ration of 1.5wt% and methanol to UCO ratio of 9:1 at 75 o C reaction temperature. The nano-catalyst showed a good catalytic activity for the feedstock containing ≤6 wt% free fatty acid. Furthermore, the catalytic activity and re-usability of the Ti(SO 4 )O for the
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Synthesis of 1,2-Disubstituted Benzimidazoles in the Presence of SBA-Pr-SO3H as a Nano Solid Acid Catalyst

Synthesis of 1,2-Disubstituted Benzimidazoles in the Presence of SBA-Pr-SO3H as a Nano Solid Acid Catalyst

was functionalized with (3-mercaptopropyl)tri- methoxysilane (MPTS) and then, the thiol groups were oxidized to sulfonic acid by hydrogen peroxide. The surface of catalyst was analyzed by different methods such as TGA, BET and CHN methods which demonstrated that the organic groups (propyl sulfonic acid) were immobilized into the pore [18]. The SEM and TEM images of SBA-Pr-SO 3 H illustrate in Figure 5. Figure 5 (a)

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Solvent-Free Synthesis of Aryl Iodide Using Nano SiO2/HIO4 as a Reusable Acid Catalyst

Solvent-Free Synthesis of Aryl Iodide Using Nano SiO2/HIO4 as a Reusable Acid Catalyst

In continuation of our previous researches on the synthesis and application of solid acid catalysts and supported reagents in organic syntheses [16], we describe the facile and modified synthesis of aryl iodides in the presence of nano-SPIA. In this work, a stable diazonium salt was formed under solvent-free conditions at room temperature (Scheme 1).

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Nano Silica/ HIO4 as a Green and Reusable Catalyst for Synthesis of 2-Naphthol Azo Dyes under Grinding Conditions

Nano Silica/ HIO4 as a Green and Reusable Catalyst for Synthesis of 2-Naphthol Azo Dyes under Grinding Conditions

have reported the diazotization of aniline derivatives by solid acids such as silica sulfuric acid [8], clay [9], lead and triethylammoniumformate [10], p-toluenesulfonic acid [11], and ionic liquid [12]. Azo dyes can alsobe obtained under solvent- free condition [13,14]. Synthesis of azo compounds with nanosized iron-promoted reductive coupling of aromatic nitro compounds has been reported [15]. Here, we wish to report a convenient and one-pot method for diazotization and diazo coupling reactions by using nano-SPIA under solvent-free conditions at room temperature by grinding.
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Biodiesel production from used cooking oil using a novel surface functionalised TiO2 nano-catalyst

Biodiesel production from used cooking oil using a novel surface functionalised TiO2 nano-catalyst

nano-catalyst and methanol (Sigma-Aldrich) were charged into the batch reactor. The three-phase (solid-liquid-liquid) mixture was mixed at 600 RPM and heated to specified temperatures and times. The final reaction mixture was transferred into a separating funnel and allowed to cool to room temperature. A few millilitres of aliquot was withdrawn from the upper layer, biodiesel phase, and separated from the remaining impurities using a centrifuge at 9000 RPM for 10 mins to quantify the fatty acid methyl ester (FAME) content of the samples by off-line gas chromatography (GC) [4].
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Nano sodalite as solid base catalyst for knoevenagel condensation reaction

Nano sodalite as solid base catalyst for knoevenagel condensation reaction

Over the last 40 years, various solid acids and bases have been developed. Nowadays, solid acid-base catalysis is one of the economically and ecologically important fields in catalysis [1]. From the statistical survey, more than hundred types of industries processes are using acid as catalyst. On the other hand, base catalyst is far less behind. Thus, the emergence of novel solid base materials makes the new base-catalyzed reactions become commercially relevant. Based on this, fundamental studies on solid bases become necessary in order to achieve the success like those of solid acids catalysts.
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SnCl4/nano-sawdust as an Efficient Bio-based Catalyst for the Synthesis of 2-Substituted Benzothiazoles and Benzimidazoles

SnCl4/nano-sawdust as an Efficient Bio-based Catalyst for the Synthesis of 2-Substituted Benzothiazoles and Benzimidazoles

SnCl 4 /nano-sawdust was prepared as a carbohydrate-based catalyst containing of tin bearing cellulose units. The catalyst was characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT- IR), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS). The catalyst was applied successfully as a readily available, inexpensive, biodegradable and environmentally benign heterogeneous bio-based solid acid for the one pot synthesis of 2-substituted benzimidazoles and benzothiazoles.

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Preparation, Characterization and Catalytic Activity of Alkyl Benzene Sulfonic Acid Carbon Based Acid Catalyst

Preparation, Characterization and Catalytic Activity of Alkyl Benzene Sulfonic Acid Carbon Based Acid Catalyst

was also functionalized with sulfonate groups by putting the material in the vapor of fuming sulfuric acid inside an autoclave. Ryoo et al. [15] synthesized an ordered mesoporous carbons (OMCs) through the nanocasting technique using OMCS as templatesor via self-assembly of phenolic resins and block copolymers [16] [17]. These materials exhibit high surface area, narrow pore size distribution, and large pore volume. Recently, a new class of sulfonated carbons (C-SO 3 H) derived from the incomplete carbonization of simple sugars and starch

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Production of biodiesel from jatropha curcas oil using solid heterogeneous acid catalyst

Production of biodiesel from jatropha curcas oil using solid heterogeneous acid catalyst

Biodiesel produced by the transesterification of vegetable oils is a promising alternative fuel to diesel because of limited fossil fuel resources and environmental concerns. The use of heterogeneous catalysts greatly simplifies the technological process by facilitating the separation of the post-reaction mixture. The use of heterogeneous catalysts greatly simplifies the technological process by facilitating the separation of the post-reaction mixture. The purpose of the present work was to examine a heterogeneous catalyst, in particular, to produce methyl esters of jatropha curcas oil (JCO). In this study, the trans esterification of JCO with methanol was studied in a heterogeneous system, using Mg-Al hydrotalcites as solid base catalysts. The dependence of the conversion of JCO on the reactions variables such as the molar ratio of methanol/ oil, the amount of catalysts used, reaction temperatures and reaction times were performed. The conversion of 99% was achieved under the optimum reaction conditions.
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Sulfonic acid-functionalized polyallylamine (sevelamer) as an efficient reusable strong solid acid catalyst for the synthesis of xanthenes derivatives

Sulfonic acid-functionalized polyallylamine (sevelamer) as an efficient reusable strong solid acid catalyst for the synthesis of xanthenes derivatives

lyst for the synthesis of 1,8-dioxo-octahydroxanthene derivatives in summary. This catalyst could be easily separated from the reaction mixture and directly reused after a simple extraction step. The catalyst was recycled for seven consecutive cycles without any obvious loss in its catalytic activity. As a good heterogeneous solid acid, S-SO 3 H is stable in air, easy to prepare and can be recov-

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Synthesis, Characterization of Highly Efficient SO 42 / CeO 2–ZrO2 Solid Acid Catalyst and Activity Studies of 2, 4, 5-triaryl imidazoles

Synthesis, Characterization of Highly Efficient SO 42 / CeO 2–ZrO2 Solid Acid Catalyst and Activity Studies of 2, 4, 5-triaryl imidazoles

catalyst was prepared by a homogeneous co-precipitation method. For this purpose, requisite quantities of zirconium oxychloride and ceric ammonium nitrate were taken and dissolved separately in deionized water. These resultant mixtures were precipitate with ammonia with dynamic stirring and maintain pH of the solution up to 8–9. At this pH, a yellow precipitate was produced and the precipitate was authorized to resolve for 12 Hours. The following precipitate was filtered off and washed sometimes with deionized water and dried at 110 ° C for 12 hrs. The powder was crushed and oven-dried. This dried powder was deep in 0.5M chlorosulphonic acid (in dichloroethane). The overload dichloroethane was evaporated by heating on hot plate. The resultant catalyst was oven-dried at 110 ° C for 12 h, calcined at 650 ° C for 4hrs.
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Fuel Cells Science and Technology 200627-33

Fuel Cells Science and Technology 200627-33

In a Plenary talk, Gottesfeld focused on some of the important milestones along the paths of polymer electrolyte fuel cell (PEFC) and direct methanol fuel cell (DMFC) science and technolo- gy, culminating in a new polymer electrolyte DMFC concept developed at MTI Micro Fuel Cells Inc. These milestones include reducing the platinum loadings of solid PEFCs by an order of magnitude, by impregnating the catalyst with Nafion ® perfluorosulfonic acid polymer (in 1986), fabricating electrodes by the application of cata- lyst/Nafion ® ‘inks’ in 1992, and developing PEFCs capable of tolerating a concentration of 100 ppm of carbon monoxide in the hydrogen fuel by incorporating a small oxygen bleed into the fuel to oxidise the impurities on the anode (in 1998). The latest development is the Mobion ® DMFC system, providing a high power density and high efficiency, up to 1100 Wh l –1 , as compared with
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Facile Strategy for Surface Functionalization of Corn Cob to Biocarbon and Its Catalytic Performance on Banana Peel Starch Hydrolysis

Facile Strategy for Surface Functionalization of Corn Cob to Biocarbon and Its Catalytic Performance on Banana Peel Starch Hydrolysis

simple reaction was introduced for sulphonation process using citric acid and hydroxyl ethyl sulphonic acid by hydrothermal treatment for 180 o C, 4 hours which using carbohydrate as carbon precursor [14]. The sulphonation by hydrothermal treatment is an efficient and environmentally friendly process. The sulphonated carbon material is one alternative that can be used in the process of hydrolysis of glucose [2] beside use liquid acids or enzymes and biodiesel production [15]. Starch is an attractive feedstock for the chemical industry, pharmaceutical, as raw materials for bioethanol and other agro-industry. There was studied about the investigation of cassava starch which has antioxidant activity [16] and edible film production [17]. Banana peel starch was used on this work, the advantages of this material are to reduce food waste and make it more valuable. This study was conducted to determine the potential and ability of corn cob as sulphonated biocarbon catalyst that can be developed into new candidate as heterogeneous catalysts. The performance of catalyst on banana peel hydrolysis was also investigated. The utilization of corn cob can be enhanced of corn cob, it is not just a waste or animal feed but can be utilized as a heterogeneous catalyst as a solid acid catalyst.
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An Alternate Green Route to Synthesis of Mono and Diesters using Solid Acid Catalysts

An Alternate Green Route to Synthesis of Mono and Diesters using Solid Acid Catalysts

The mono ester was prepared in first step by taking equimolar proportion of acid and alcohol were taken in a round bottomed flask and the reaction mixture stirred at ~80°C for DEM and DES, ~115°C for DBP and ~140°C for DOP for about 10-15 min in absence of any catalyst and solvent. The dicarboxylic acid/anhydride gets completely converted to the monoester, and the acid concentration at this stage is taken as the initial concentration. The obtained product was then subjected to further esterification reaction by adding second mole of respective alcohol, catalyst (0.10 - 0.25 g) and 10 mL solvent. The reactions were carried out optimizing several parameters such as reaction time, catalyst amount and mole ratio of reactants. The temperature parameter has not been varied as discussed in synthesis of monoesters. After completion of reaction, catalyst was separated by decantation and reaction mixture was distilled to obtain the product.
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Improvement of Sludge Reduction Efficiency of Ozonation by Microbubble Aeration Technology and Catalysis

Improvement of Sludge Reduction Efficiency of Ozonation by Microbubble Aeration Technology and Catalysis

3.3. Efficiency of Microbubble Ozonation Catalyst on COD Rapid injection of ozone at the beginning of reaction appears to be effective for the disintegration, ozonation can be determined by the increase in the value of COD during the experiment. This hypothesis has been supported by Sludge disintegration by ozone can be described as sequential decomposition reactions of the cell destruction, solubilization and subsequent oxidation of the released organics into carbon dioxide[19]. Ozone releases the soluble substances in the activated sludge which increases the COD, disrupts intracellular cell bodies and dissolution of sludge. By deducting the destruction of the organic cell in the activated sludge was the result of an increase in COD. Although comparison of the efficiency of sludge, in this study the COD increased 220.8% (Fig.6), two reasons were affected this result one was the property of H2O2 the second was the due of ozone-bubble amount, reported the efficiency of COD removal was 20% higher in the microbubble system. These results revealed that microbubble ozonation is a promising process in wastewater treatment H2O2 really affected the COD increasing which was 47.89% without catalyst with an ozone dose 0.35 g O 3 g -1 TSS. This hypothesis was based on
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Acid-Base Bifunctional Hf Nanohybrids-Enabled High Selectivity in Catalytic Conversion of Ethyl Levulinate to γ-Valerolactone

Acid-Base Bifunctional Hf Nanohybrids-Enabled High Selectivity in Catalytic Conversion of Ethyl Levulinate to γ-Valerolactone

BET (Brunauer-Emmett-Teller) surface areas of the porous materials were determined from nitrogen physisorption measurements at liquid nitrogen temperature on a Micromeritics ASAP 2460 instrument. FT-IR (Fourier transform infrared spectrometer) spectra were measured by Thermo Fisher Nicolet iS50 spectrometer in wavenumber range of 400-4000 cm -1 . The Lewis and Brønsted acid sites of PPOA-Hf was determined by vacuum adsorption surface reaction infrared in situ characterization analysis system (Dalian Institute of Chemical Physics, Chinese Academy of Sciences) with Thermo Fisher Nicolet iS50 AEM in wavenumber range of 1400-1600 cm -1 . Content of Hf and P species in reaction system were determined by inductively coupled plasma-optical emission spectrometer (ICP-OES) on a PerkinElmer Optima 5300 DV. STEM (scanning transmission electron microscopy) and TEM (Transmission electron microscope) test was measured by JEOL 2100 TEM/STEM. Thermogravimetry (TG) analysis was carried out by a NETZSCH STA 449 F3 Jupiter thermal gravimetric analyzer. The acidity and basicity of catalysts were measured by NH 3 -TPD and CO 2 -TPD (temperature
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Keggin Structure and Surface Acidity of 12 Phosphotungstic Acid Grafted Zr MCM 48 Mesoporous Molecular Sieves

Keggin Structure and Surface Acidity of 12 Phosphotungstic Acid Grafted Zr MCM 48 Mesoporous Molecular Sieves

The thermal and hydrothermal stability of Si-based MCM-48 could be improved by framework modification. Zhang and coworkers recently report that zirconium modified MCM-48 could remain its cubic mesoporous structure even after calcination at 800˚C for 4 h or after hydrothermal treatment in water at 100˚C for 24 h [10]. Incorporations of rare metals such as La [11] and Ce [12] and transition metals like Fe [12], Mn [13], Ti [14], Sn [15], W [16], V [17], Cu [18] and Zn [18] etc. into the framework of the MCM-48 have been also reported. These incorporated metal ions may serve as active sites or structural stabilizers of the MCM-48 solid.
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Nano Titanium Dioxide: Efficient and Reusable Heterogeneous Nano Catalyst for Synthesis of 1,8-Dioxo-Decahydroacridines

Nano Titanium Dioxide: Efficient and Reusable Heterogeneous Nano Catalyst for Synthesis of 1,8-Dioxo-Decahydroacridines

3,3,6,6-Tetramethyl-9-phenyl-3,4,6,7,9,10-hexahydroacridine-1,8- (2H,5H)-dione derivatives are synthesized by nano titanium dioxide as an efficient and reusable heterogeneous nano catalyst in a one pot multi component reaction. Easy preparation and separation of catalyst, simply workup procedure, clean reaction and reusability of the catalyst up to 7 times without appreciable loss of its catalytic activity and high yields are some advantages of this work.

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MONTMORILLONITE: A MILD AND EFFICIENT RECYCLABLE SOLID ACID CATALYST FOR DETRITYLATION OF TRITYL TETRAZOLE IN SARTAN MOLECULES

MONTMORILLONITE: A MILD AND EFFICIENT RECYCLABLE SOLID ACID CATALYST FOR DETRITYLATION OF TRITYL TETRAZOLE IN SARTAN MOLECULES

removal of trityl groups involve reductive protocols (e.g. Li powder and a catalytic amount of naphthalene). [13] Many manufacturing reactions for fine chemicals and pharmaceuticals rely on homogeneous Lewis acid catalysts. However above methods have associated drawbacks, such as long reaction times, use of hazardous reagents and the inability to recycle. In recent years, heterogeneous catalysts have gained significant importance from environmental and economical stand points, recently reported two methods in this era were silica absorbed sulfuric acid [14] and silica gel supported ceric ammonium nitrate [15] for detritylation. The use of clays as catalysts and catalyst supported has received considerable attention recently [16,17] .Herein, we report a environmental and economical benign deprotection of trityl group in trityl tetrazole sartan molecules by proton and metal ion- exchanged montmorillonite, a heterogeneous solid acid catalyst which is reusable and
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Experimental Investigations on CI Diesel Engine with Varied Combustion Chamber Designs ( HCC And SDCC) using Neem Biodiesel and Calcium Carbonate (Caco3) Nano Fluid Additive

Experimental Investigations on CI Diesel Engine with Varied Combustion Chamber Designs ( HCC And SDCC) using Neem Biodiesel and Calcium Carbonate (Caco3) Nano Fluid Additive

to its less cost when compared to petrol fuels, using of fossil fuels in a larger quantities will leads to the scarcity, in order to overcome this problem alternative fuels are introduced. Biodiesel is an alternative source for diesel fuel in C I Diesel engines due to its significant performance and Environmental benefits From previous researches it is learnt that neem biodiesel will be used as an alternate fuel but in percentages (B10,B20..). But in this work an attempt is made using neem biodiesel (B100) with different combustion chambers that are hemispherical combustion chamber (HCC) and shallow depth combustion chambers (SDCC) to find the better combustion characteristics and to reduce heat losses to obtain maximum efficiency in diesel engine. Neem biodiesel alone will not solve the dependence on alternate fuel because it contains high viscosity, density and low calorific value, to improve the properties of neem biodiesel nano fluid additive is added to it to make biodiesel as a high calorific fuel. calcium carbonate is best suited as a nano additive due to its beneficial properties. An experimental investigation are carried out on a single cylinder, four stroke, naturally aspirated, direct injection and water cooled diesel Engine with a compression ratio of 17.5:1 and brake power output of 5.2 kW at 1500 rev/min using neem biodiesel and caco 3 nano fluid in two proportions
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