Calcium Methoxide Research Articles

PEMANFAATAN ABU CANGKANG KERANG DARAH (ANADARA GRANOSA) SEBAGAI KATALIS DALAM PEMBUATAN METIL ESTER DARI MINYAK JELANTAH

Transesterification is the reaction to produce methyl esters in which this reaction’s involves catalyst of blood clam shell ashes of combustion at temperatures of 900 ° C for 3 hours and the amount of ash that is used by 8%, 10%, 12% (w / w). Ash used in dissolved in methanol with a molar ratio of methanol: oil of 9: 1, 12: 1 (n / n) to obtain a compound of calcium methoxide. Used cooking oil is filtered and then esterified with catalyst 3.0% (w / w) H2SO4 98% and methanol: oil TG (6: 1) to reduce the FFA to <1%. Transesterification reaction is carried out at a reaction temperature of 65 ° C for 3 hours, and keep stirring 700 rpm. Quantitatively, the optimum yield of methyl ester in the amount of ash produced is 12% (w / w) and the molar ratio of methanol: oil at 12: 1 (n / n) of 56.51% with specification methyl esters such as density, kinematic viscosity and purity methyl ester biodiesel in accordance with SNI 04-7182-2006, based on the analysis of GC (Gas Chromatography), the purity of the resulting methyl ester was 98.79%.

Hydrothermal effect on synthesis, characterization and catalytic properties of calcium methoxide for biodiesel production from crude Jatropha curcas

Hydrothermal synthesis is a well-suited approach for preparing bulk metal catalysts with high purity as it is cost-effective and easy to control in terms of temperature and time.

<sup> </sup>Transesterification of <i>Pongamia pinnata </i>Oil into Biodiesel Using Quick Lime Based Calcium Methoxide as Catalyst

The calcium methoxide was synthesized as catalyst from quick lime for biodiesel production of Pongamia pinnata (P. pinnata) oil. The catalyst was further characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), attenuated total reflection fourier transform (ATR-FTIR), energy dispersive X-ray spectroscopies (EDX) and BET surface area analysis to evaluate its performance. The parameters affecting the fatty acid methyl ester (FAME) content such as catalyst concentration, methanol to oil molar ratio and reaction time were investigated. Under optimized reaction condition, the FAME yield at 93.94 % was achieved within 3 h using 3 % wt catalyst concentration, 15:1 methanol to oil molar ratio, 65 °C reaction temperature and 750 rpm stirring rate. The result of FAME suggested that calcium methoxide catalyst has promising viability in transesterification for biodiesel production.

Transesterification of Nannochloropsis oculata microalga's oil to biodiesel using calcium methoxide catalyst

Biodiesel is an environmental friendly liquid fuel similar to conventional diesel in combustion properties. It has received international attention in recent times, as that biodiesel is renewable, non-toxic and safe to store. In this study, high grade biodiesel was produced from microalgae (Nannochloropsis oculata) derived lipids via transesterification reaction with methanol in the presence of heterogeneous Ca(OCH3)2 (calcium methoxide) catalyst. The biodiesel was produced with high yield; (92%) at 60 °C compared to the highest yield reported as 22% with the use of a Mg–Zr catalyst. The product exhibited excellent performances. The catalyst was characterized by TG/DTA (thermogravimetric-differential thermal analyses), XRD (X-ray diffraction), BET (Brunauer – Emmett – Teller), FTIR (Fourier transform infrared), SEM-EDX (scanning electron microscopy-energy dispersive spectrometer) and TEM (transmission electron microscopy) analysis. The effect of different reaction parameters including reaction time, methanol/oil molar ratio and catalyst dosage on the yield of FAME (fatty acid methyl ester) was studied. Interestingly, the catalyst can be reused five times successively without affecting the biodiesel yield. Biodiesel produced from microalgae oil consists of high levels of polyunsaturated fatty acids, making it highly suitable as winter grade biodiesel.

Green nano-catalyst for methanolysis of non-edible Jatropha oil

Non-edible feedstocks are regarded as a sustainable source of renewable energy. In order to find renewable, cheaper and easier methods to obtain energy, attention has been paid to develop potential green catalyst to produce renewable biodiesel. The catalyst was characterized by X-ray diffraction (XRD) results in combination with thermogravimetry–differential thermal analysis (TG–DTA), Brunauer–Emmer–Teller (BET), Fourier transfrom-infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TEM analysis depicted that calcium methoxide (Ca(OCH3)2) catalysts were in size of 34.7nm. The reaction parameters namely; reaction time, methanol/oil molar ratio, catalyst dosage were investigated for fatty acid methyl ester (FAME) yield. The highest biodiesel yield (95%) was appraised under the optimum condition (i.e. catalyst amount of 2wt.%; methanol/oil molar ratio of 15:1, reaction time of 90min). The Ca(OCH3)2 phase of catalyst can be regarded as an active phase to get high yield of biodiesel which was confirmed from characterization study. Furthermore, important fuel properties were also investigated and satisfied the ASTM D6751 and European 14214 biodiesel standards. Thus, Ca(OCH3)2 catalyst prepared in this study was having efficient, low toxicity, cost effective and easy to prepare for green fuels production especially biodiesel.

Biodiesel Production via Transesterification of Nannochloropsis oculata microalga’s Oil Using Calcium Methoxide as Heterogeneous Catalyst

Biodiesel Production via Transesterification of Nannochloropsis oculata microalga’s Oil Using Calcium Methoxide as Heterogeneous Catalyst

Calcium Methoxide Synthesis from Quick Lime Using as Solid Catalyst in Refined Palm Oil Biodiesel Production

In this research, calcium methoxide was synthesized as solid base catalyst from quick lime for biodiesel production. The catalyst was further characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), attenuated total reflection fourier transform (ATR-FTIR) and Energy-dispersive X-ray spectroscopies (EDX) to evaluate its performance. The transesterification of refined palm oil using calcium methoxide and the process parameters affecting the fatty acid methyl ester (FAME) content such as catalyst concentration, methanol:oil molar ratio and reaction time were investigated. The results showed that the FAME content at 97% was achieved within 3 h using 3 %wt catalyst loading, 12:1 methanol:oil molar ratio and 65 °C reaction temperature. The result of FAME suggested calcium methoxide was the promising solid catalyst for substitution of the conventional liquid catalyst.

Study of Challenging Calcium Alkoxides in Solution by Electrospray Ionization Mass Spectrometry (Part 1)

Electrosprayionization was applied on calcium altkoxides studying the mostsuitableoperativeconditions for their detection/identification. To reach this aim, calcium methoxide and ethylate were obtained by two different synthetic pathways, in order to understand their possible different aggregation states. The reaction mixture shows the presence of a supernatant and of a precipitate poorly soluble in most organic solvents. The purpose of this preliminary study is to understand the qualitative differences between the precipitated species and the ones in solution by analyzing both of them with the same analytical method. The electrospray ionization (ESI) operating conditions (voltages, temperatures, solvents) allow not only the detection of single species but also the study of clusters present in solution. Particular attention was paid to establishing the role of ESI conditions in the formation of the detected species. Experiments performed at different sprayer voltages (1 kV, 2kV, 3 kV and 4 kV) proved that ESI does not perturbate the equilibria present in the original solution, demonstrating that the technique can be a useful tool to achieve information on this class of compounds.

Transesterification of canola oil catalyzed by nanopowder calcium oxide

Two types of commercial nanopowder calcium oxides, a higher surface area (HSA nano-CaO) and moderate surface area (nano-CaO) were studied for the transesterification of canola oil. The effect of reaction temperature, catalyst/oil weight ratio, and methanol/oil molar ratio on the reaction performance was investigated. The results show that nanopowder CaOs possess high activity due to their larger BET surface areas. At 65°C, 99.85% biodiesel yield was obtained at 2h when 3wt.% of the nano-CaO catalyst was used with 9:1 methanol/oil molar ratio. The required catalyst/oil weight ratio to achieve the same yield under the same conditions was 10 times less for the HSA-nano-CaO catalyst. In contrast, only 88.59% and 16.23% yield were obtained for calcium methoxide (Ca(OCH3)2) and laboratory-grade CaO, respectively. A Langmuir–Hinshelwood model-based reaction mechanism was proposed for nano-CaO catalyzed transesterification reaction. The reaction was assumed to be first order with respect to triglyceride. The apparent reaction constants, apparent activation energy and pre-exponential factors have been calculated based on experimental data. Nanopowder CaOs were capable of being used without significant deactivation for 10cycles. A slight drop in activity was ascribed to a combination of surface area loss from particle aggregation, the formation of Ca(OCH3)2, CaCO3, a Ca-glycerin complex, and adsorbed CO2 on the catalyst surface. Particle size did not have any effect on the amount of Ca leaching but leaching did increase with longer reaction time especially at higher catalyst loadings. Increasing the methanol/oil molar ratio increased Ca leaching in the glycerol-rich phase and decreased Ca leaching in the biodiesel-rich phase.

Deacidification of Jatropha Curcas Oil by Extraction for Biodiesel Production

The acid value of jatropha curcas oil is 9.41mgKOH/g. The most of fatty acids should be removed if base catalysts are adopted to catalyze the transesterification reaction for biodiesel production in case of soap formation. In this study, methanol and ethanol were adopted to extract the fatty acids in jatropha curcas oil. Then, it was catalyzed by calcium methoxide for biodiesel production. The extracted fatty acids can be used to produce biodiesel at supercritical or sulfuric acid conditions. The results indicated that the acid value of jatropha curcas oil decrease to 0.31 mgKOH/g from 9.41 mgKOH/g using ethanol extraction for 3 times at 25°C. The biodiesel yield exceeded 96% using solid base catalyst. The advantages of methanol and ethanol extractions are low oil loss and high biodiesel yield.

Synthesis and kinetics of biodiesel formation via calcium methoxide base catalyzed transesterification reaction in the absence and presence of ultrasound

The transesterification of soybean oil using calcium methoxide as solid base catalyst and the process parameters affecting the yield of biodiesel such as the catalyst concentration, methanol/oil molar ratio and the reaction temperature were investigated in detail. The results showed that the yield of biodiesel in excess of 90% was achieved within 90min using 1% catalyst loading, 9:1 methanol/oil molar ratio and 65°C reaction temperature. In addition, the effects of catalyst storage time on its activity for transesterification reaction and ultrasound at 20kHz and 611kHz frequencies on the yield of biodiesel were also evaluated. TGA–DSC and BET studies showed that the catalyst has good thermal stability and high surface area, respectively. Furthermore, the mechanism of this heterogeneously catalyzed transesterification system with and without ultrasonication was demonstrated to be a two-step reaction in which mass-transfer controlled regime is accompanied by kinetically controlled regime with both regimes following pseudo first order reaction kinetics.

Activity of Calcium Methoxide Catalyst for Synthesis of High Oleic Palm Oil Based Trimethylolpropane Triesters as Lubricant Base Stock

High oleic palm oil based trimethylolpropane triesters (TMPTE) are potential biodegradable base stocks for lubricant production. Calcium methoxide was used as a catalyst for the synthesis of TMPTE through chemical transesterification of high oleic palm oil methyl esters (POME) with trimethylolpropane (TMP). The effects of the main operating variables, i.e., temperature, pressure, molar ratio of TMP to POME, and the catalyst amount, on the yield of TMPTE were appraised. The amount of soap produced under these conditions was examined. The optimum conditions for the reaction were the reaction temperature set at 170 °C, molar ratio of TMP:POME set at 1:6, pressure of the system maintained at 50 mbar, and mass ratio of calcium methoxide set at 0.3% per weight of reaction mixture. Trimethylolpropane esters containing 98% w/w triesters were successfully synthesized under these conditions within 8 h reaction time. Saponification occurred under these conditions; however, the soap formation was less than that produced when homogeneous catalyst was used.

Synthesis and characterization of calcium methoxide as heterogeneous catalyst for trimethylolpropane esters conversion reaction

Trimethylolpropane (TMP) esters are potential biodegradable basestock for biolubricant. In order to attain environmental benignity, attention has been focused on utilizing heterogeneous catalysts for production of TMP esters. Alkaline homogeneous catalysts tend to react with free fatty acids to produce unwanted soap, thus reducing the overall product yield. This study had focused on the synthesis of calcium methoxide and investigating its potential as heterogeneous catalyst for the transesterification of TMP and palm oil methyl esters (POME) to TMP esters. The performance of synthesized calcium methoxide as a catalyst was examined by characterizing it through some instrumental techniques. X-ray diffraction (XRD) showed calcium methoxide has been successfully synthesized. Scanning electron microscopy (SEM) displayed thermally resistant surface structure with good porosity; BET showed high surface area; particle size analysis evidenced reasonable size of catalyst particles; and thermogravimetry (TGA) revealed good thermal stability of synthesized calcium methoxide. Moreover, the catalyst was found to possess mesoporous surface by pore size analysis through Barrett–Joyner–Halenda (BJH) method. The results of transesterification reaction indicated satisfactory catalytic activity of synthesized calcium methoxide and the TMP triesters yield obtained was 80.35% after 2h, 87.48% after 4h, 91.30% after 6h and 92.38% after 8h reaction time.

Bulk Ring Opening Polymerization of L‐Lactide with Calcium methoxide

AbstractSummary: Bulk ring opening polymerization (ROP) of L‐lactide (LA) initiated by calcium methoxide (Ca(OMe)2) was investigated in LA/Ca molar ratio from 100 to 5000 and reaction times up to 3h at 180 °C. Ca(OMe)2 showed good activity as ROP catalyst, particularly at high catalyst concentration. The polymerization shows a linear relationship between $\overline {{\rm M}} $n and reaction time, typical of a controlled process. The increase of LA/Ca molar ratio decreases the conversion which was maximum (66%) when the polymerization was carried out at 180 °C and LA/Ca = 100. Semicrystalline poly(L‐lactic acid) (PLLA) with moderate $\overline {{\rm M}} $n varying from 8,500 to 19,500 and polydispersities from 1.20 to 1.44 were obtained. The increase of LA/Ca molar ratio decreased $\overline {{\rm M}} $n, increased the degree of crystallinity and decreased racemization processes which can be controlled by the polymerization condition. Racemization could be reduced by using low catalyst concentration.

On the deactivation of alkali solid catalysts for the synthesis of glycerol carbonate from glycerol and dimethyl carbonate

The deactivation of alkali solid catalysts for the synthesis of glycerol carbonate from glycerol and dimethyl carbonate was investigated. Calcium oxide, calcium hydroxide and calcium methoxide were chosen as the representatives of the alkali solid catalysts. When the catalysts were recycled, the yield of glycerol carbonate decreased dramatically. The alkali solid catalyst was converted to the basic calcium carbonate Cax(OH)y(CO3)z, which was the cause of the decrease of glycerol carbonate yield. It was found that the chemical interactions of the alkali solid catalyst with glycerol and glycerol carbonate led to the formation of the basic calcium carbonate Cax(OH)y(CO3)z, for which the mechanism was proposed. Based on the deactivation mechanism, calcium diglyceroxide was adopted as a new catalyst for the transesterification of glycerol and dimethyl carbonate. Compared to calcium oxide, calcium hydroxide and calcium methoxide, calcium diglyceroxide showed excellent reusability for the transesterification of glycerol and dimethyl carbonate. For calcium oxide, calcium methoxide and calcium diglyceroxide, there were dissolution losses of the catalysts in the reaction medium. For calcium hydroxide, the catalyst dissolution loss in the reaction medium was nearly negligible. For calcium diglyceroxide, the dissolution of the catalyst in the reaction medium did not influence the yield of glycerol carbonate significantly.

New synthesis route of hydrocalumite-type materials and their application as basic catalysts for aldol condensation

An attempt was made to directly synthesize a Brønsted-type catalyst based on the hydrocalumite-like structure by controlled hydrolysis of calcium and aluminium alkoxides. Solids belonging to the AFm and hydrogrossular families were obtained by dissolution of calcium methoxide and aluminium triethoxide precursors in water at a molar ratio [Ca 2+]/[Al 3+] = 2.0, followed by an aging of the precipitate at different temperatures. At 273 K, a mixture of gibbsite, layered hydrocalumite-like phase, and 3 dimensional cubic Si-free katoite compounds was obtained. At 298 K, the XRD pattern reveals the presence of hydrocalumite-like phases intercalated by OH − and CO 3 2− species, respectively, as confirmed by IR spectroscopy. This as-prepared sample behaved as an efficient Brønsted-type catalyst able to perform the condensation reaction of benzaldehyde and acetone into benzylideneacetone. At 333 K, the catalytically inactive katoite phase alone was formed.

Heterogeneous catalytic transesterification of phosphatidylcholine

The transesterification of phosphatidylcholine (PC) via homogeneous and heterogeneous catalysis was investigated for the production of fatty acid methyl esters (FAME) i.e. biodiesel. Calcium methoxide and calcium oxide were used as heterogeneous catalysts, and KOH as a homogeneous catalyst for the transesterification of phosphatidylcholine (PC)--a polar phospholipid prevalent in eukaryotic organisms. The initial reaction rate was higher for KOH (24.23 g of FAME/g of catalyst.min) than for calcium methoxide (17.06 g of FAME/g of catalyst.min) and calcium oxide (1.06 g of FAME/g of catalyst.min). PC was then mixed with soybean oil at different proportions (i.e. 10%, 30% and 50%, PC10, PC30 and PC50, respectively) which was then used as the feedstock for transesterification using calcium methoxide. When the mass fraction of PC was increased in the feedstock reaction rate also increased. Phosphorus content of the FAME layer of PC100, PC50, PC30 and PC10 was 0.081, 0.041, 0.035 and 0.028% (w/w), respectively.

Synthesis of biodiesel from rapeseed oil using supercritical methanol with metal oxide catalysts

This study examined the synthesis of biodiesel using supercritical or subcritical methanol with metal oxide catalysts. The transesterification of rapeseed oil was carried out with the metal oxide catalysts (SrO, CaO, ZnO, TiO(2) and ZrO(2)) to determine the most effective heterogeneous catalyst having the highest catalytic activity with minimum weight loss caused by dissolution. SrO and CaO dissolved in the biodiesel during the reaction because they were transformed to strontium methoxide and calcium methoxide, respectively. ZnO was the optimum catalyst for the transesterification of rapeseed oil owing to its high activity and minimum weight loss in supercritical methanol. The optimal reaction conditions included a molar ratio of methanol to oil of 40 in the presence of 1.0wt.% ZnO and a reaction time of 10min. The supercritical process with ZnO as a catalyst appears economically viable.

Synthesis and characterization of calcium β-diketonate complexes. X-Ray crystal and molecular structures of: [{Ca(tmhd)2}2(18-crown-6)], [Ca(dpp)2(thf)2] and [Ca(dpp)2(triglyme)

Reactions of 2,2,6,6-tetramethyl-3,5-heptanedione (Htmhd), 1,1,1,5,5,5-hexafluoro-2,4-pentanedione (Hhfa) or 1,3-diphenyl-1,3-propanedione (Hdpp) with calcium methoxide in hexane or toluene afford the corresponding known oligomeric beta-diketonates: [Ca(3)(tmhd)(6)], [{Ca(hfa)(2)}(n)] and [{Ca(dpp)(2)}(n)]. The complexes react with tetrahydrofuran, 2,5,8,11-tetraoxadodecane (triglyme) or 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6) leading to the formation of the new mononuclear [Ca(dpp)(2)(thf)(2)], [Ca(dpp)(2)(triglyme)] and dinuclear [{Ca(dpp)(2)}(2)(18-crown-6)] and [{Ca(tmhd)(2)}(2)(18-crown-6)] adducts. The obtained complexes were characterized by elemental analyses, IR, (1)H and (13)C NMR spectroscopies; moreover, single crystal X-ray diffraction measurements were also carried out for: [{Ca(tmhd)(2)}(2)(18-crown-6)], [Ca(dpp)(2)(thf)(2)] and [Ca(dpp)(2)(triglyme)].

Active phase of calcium oxide used as solid base catalyst for transesterification of soybean oil with refluxing methanol

Abstract For developing a process of biodiesel production with environmental benignity, much interest has been focused on solid base catalysts such as calcium oxide for transesterification of vegetable oils with methanol. In this paper, the active phase of calcium oxide was investigated by characterizing the catalyst collected after achieving the conversion of edible soybean oil into its methyl ester at reflux of methanol in a glass batch reactor. Calcium oxide combined with the by-produced glycerol, so that calcium diglyceroxide was a major constituent of the collected catalyst. The absence of calcium methoxide was clear from the spectrum of solid-state 13C-NMR. The chemical change of calcium oxide was not observed, when the yield of FAME reached 30%. The collected catalyst was not as active as the fresh one (calcium oxide), but was reused without any deactivation. In order to identify the active phase of the collected catalyst, we prepared calcium diglyceroxide by immersion of calcium oxide with refluxing methanol in the presence of glycerol. Calcium diglyceroxide prepared as the reference sample was as active as the collected catalyst in the transesterification, and was tolerant to air-exposure.