Transesterification of Jatropha Oil over Ceria-Impregnated ZSM-5 for the Production of Bio-Diesel

Bhagiyalakshmi, Margandan,Vinoba, Mari,Grace, Andrews Nirmala Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.10

In this study transesterification of Triglycerides (TG) from Jatropha curcas oil (JCO) with methanol for production of biodiesel was investigated over cerium impregnated ZSM-5 catalysts. NaZSM-5 was synthesized in an alkaline medium and impregnated with cerium oxide by wet method using cerium nitrate as a source for cerium. They were characterized by X-ray diffraction (XRD), Thermogravimeteric analysis (TGA), $CO_2$-temperature programmed desorption, and $N_2$ adsorption/desorption analysis. XRD analysis showed decrease in intensity of the patterns with the increase in the ceria loading but crystallization of ceria to larger size is an evident for 10 and 15% loading. The optimal yield of transesterification process was found to be 90% under the following conditions: oil to methanol molar ratio: 1:12; temperature: $60^{\circ}C$; time: 1 h; catalyst: 5 wt %. Here the yield of fatty acid methyl ester (FAME) was calculated through $^1H$ NMR analysis. The investigation on catalyst loading, temperature, time and reusability illustrated that these ceria impregnated NaZSM-5's were found to be selective, recyclable and could yield biodiesel at low temperature with low methanol to oil ratio due to the presence of both Lewis and Bronsted basicity. Hence, from the above study it is concluded that ceria impregnated ZSM-5 could be recognized as a potential catalysts for biodiesel production in industrial processes.

Dexterous template-free synthesis of ferrisilicate with MFI morphology using rice husk ash

Bhagiyalakshmi, Margandan,Anuradha, Ramani,Palanichamy, Muthiahpillai,Jang, Hyun Tae Elsevier 2010 Journal of non-crystalline solids Vol.356 No.23

<P><B>Abstract</B></P><P>Sodium silicate, the supernatant solution extracted from rice husk ash was used as silica source in hydrothermal synthesis of Fe ZSM-5 zeolites by an organic-free method. Characterization techniques such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), BET, X-Ray Fluorescence (XRF), Diffuse Reflectance Spectroscopy — Ultra Violet (DRS-UV) and Temperature-Programmed Desorption-ammonia (NH<SUB>3</SUB>-TPD) unambiguously confirm the formation of Fe ZSM-5. Phosphoric acid used in the synthesis, forms an oxo-anion complex with iron and this complex acts as surface directing agent in the formation of Fe ZSM-5 zeolites. Characterization results prove that rice husk ash can successfully be recycled as ferrisilicates with MFI morphology even in the absence of template.</P>

Synthesis of copper exchanged heteropolyacids supported on MCM-48 and its application for CO_2 adsorption

Margandan Bhagiyalakshmi,장현태,PUSHPARAJHEMALATHA,Mani Ganesh,Mei Mei Peng 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.3

Copper-encapsulated heteropolyacid-impregnated mesoporous MCM-48 (Cu-HPA-MCM-48) with copper in a reduced state was synthesized, and the CO_2 adsorption capacity was monitored. The synthesized material was characterized by XRD, N_2 adsorption–desorption, FT-IR, DSC, CO_2-TPD and XPS. The low angle X-ray diffraction pattern of the Cu-HPA-MCM-48 demonstrates the encapsulation of copper inside the pore by the disappearance of higher-order peaks. This result is further supported by the presence of Cu_(2p)^3 andW4f peaks in XPS. The CO_2 adsorption capacity of Cu-HPA-MCM-48was 70 mg/g at 25℃. The energy of desorption and the heat of the reaction (DHr) were 21.2 kJ/mol and 490 Btu/lb,respectively, as determined by CO_2-TPD and DSC. As the DHr value of Cu-HPA-MCM-48 approaches the CO_2 benchmark value (580 Btu/lb), the catalyst exhibited improved CO_2 capturing capacity.

Transesterification of Jatropha Oil over Ceria-Impregnated ZSM-5 for the Production of Bio-Diesel

Margandan Bhagiyalakshmi,Mari Vinoba,Andrews Nirmala Grace 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.10

In this study transesterification of Triglycerides (TG) from Jatropha curcas oil (JCO) with methanol for production of biodiesel was investigated over cerium impregnated ZSM-5 catalysts. NaZSM-5 was synthesized in an alkaline medium and impregnated with cerium oxide by wet method using cerium nitrate as a source for cerium. They were characterized by X-ray diffraction (XRD), Thermogravimeteric analysis (TGA), CO2- temperature programmed desorption, and N2 adsorption/desorption analysis. XRD analysis showed decrease in intensity of the patterns with the increase in the ceria loading but crystallization of ceria to larger size is an evident for 10 and 15% loading. The optimal yield of transesterification process was found to be 90% under the following conditions: oil to methanol molar ratio: 1:12; temperature: 60 °C; time: 1 h; catalyst: 5 wt %. Here the yield of fatty acid methyl ester (FAME) was calculated through 1H NMR analysis. The investigation on catalyst loading, temperature, time and reusability illustrated that these ceria impregnated NaZSM-5’s were found to be selective, recyclable and could yield biodiesel at low temperature with low methanol to oil ratio due to the presence of both Lewis and Bronsted basicity. Hence, from the above study it is concluded that ceria impregnated ZSM-5 could be recognized as a potential catalysts for biodiesel production in industrial processes.

Effect of Bimetallic Pt-Rh and Trimetallic Pt-Pd-Rh Catalysts for Low Temperature Catalytic Combustion of Methane

Bhagiyalakshmi, Margandan,Anuradha, Ramani,Park, Sang-Do,Park, Tae-Sung,Cha, Wang-Seog,Jang, Hyun-Tae Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.1

Monometallic, bimetallic and trimetallic particles consisting of different weight compositions of Pt-Pd-Rh over pure alumina wash coats have been synthesized and their catalytic performance on methane conversion was studied from 150 to $600^{\circ}C$. Different catalyst formulations with variable Pt, Pd and Rh contents for bimetallic and trimetallic systems were tried and $Pt_{(1.5)}Rh_{(0.3)}/Al_2O_3$ and $Pt_{(1.0)}Pd_{(1.0)}Rh_{(0.3)}/Al_2O_3$ shows low $T_{50}$ and $T_{90}$ temperatures. Bimetallic and trimetallic particle synergism acts as three way catalysts and therefore, all the catalysts show 100% methane conversion. The effect of supports such as $ZrO_2$ and $TiO_2$ on methane combustion was investigated; from $T_{50}$ and $T_{90}$ results both $Al_2O_3$ and $ZrO_2$ are suitable supports for low temperature methane combustion.

Role of ceria in CO2 adsorption on NaZSM-5 synthesized using rice husk ash

PUSHPARAJHEMALATHA,Margandan Bhagiyalakshmi,Mani Ganesh,Muthaihpillai Palanichamy,Velayutham Murugesan,장현태 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.1

Ceria (3, 5, 7, 11, 19 wt%) impregnated NaZSM-5 was synthesized and studied for adsorption of CO2. They were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive Xray analysis (EDS), CO2-temperature programmed desorption (CO2-TPD) and Brunauer–Emmett–Teller (BET) techniques. The heat of the reaction (DHr) derived from differential scanning calorimetry (DSC)analysis was 490 Btu/lb. XRD analysis showed a decrease in the intensity of patterns with the increase in the ceria loading but crystallization of ceria to larger size was clearly evident for 11 and 19% loading. The surface area decreased for 3 and 5% loading, but increased for 7, 11 and 19% loading illustrating difference in dispersion. The maximum adsorption capacity of CeO2(5%)/NaZSM-5 was 130 mg/g of sorbent. Extraction of silica from the agricultural waste, rice husk, and its use in the zeolite synthesis was an advantage in this study. Hence, from the study it was concluded that ceria impregnated NaZSM-5 could be treated as a novel material for CO2 adsorption, as they were regenerable and recyclable. This study can also be applied to all other zeolites.

Determination of Letrozole in formulation by a Validated RP-HPLC method

Mani Ganesh,Margandan Bhagiyalakshmi,Mari Vinoba,Hyun Tae Jang 한국산학기술학회 2010 한국산학기술학회 학술대회 Vol.- No.-

A simple, rapid and validated reversed phase liquid chromatographic method has been developed for the determination of Letrozole (LZ) in pharmaceutical dosage. LZ was separated on ODS analytical column with a mixture of acetonitrile, water in the ratio 50:50 (v/v) as mobile phase at a flow rate of 1.0 mL /min. The effluent was monitored by UV detection at 265nm. Calibration plot was linear in the range of 160 to 240 µg/mL with the linear regression (r) = 0.999. The method was validated for recovery, precision, specificity.

Harvesting CaCO₃ Polymorphs from In Situ CO₂ Capture Process

Vinoba, Mari,Bhagiyalakshmi, Margandan,Choi, Song Yi,Park, Ki Tae,Kim, Hak Joo,Jeong, Soon Kwan American Chemical Society 2014 The Journal of Physical Chemistry Part C Vol.118 No.31

<P>The in situ sequestration of CO<SUB>2</SUB> using alkanolamine and organometallic calcium (OMC) offers an ecofriendly method for synthesizing a diverse range of calcite, vaterite, and aragonite polymorphs of CaCO<SUB>3</SUB>. Aqueous <I>N</I>-methyldiethanolamine (MDEA) has high CO<SUB>2</SUB> loading capacity with low regeneration energy, but rate of CO<SUB>2</SUB> absorption was found to be slow. The driving force for the binding between CO<SUB>2</SUB> and MDEA could be enhanced by the presence of bovine carbonic anhydrase (bCA). The absorbed CO<SUB>2</SUB> was converted to stable carbonates through the addition of an OMC. The bCA enzyme both accelerated the CO<SUB>2</SUB> absorption and mineralization in the amine–CO<SUB>2</SUB>–OMC system and improved the catalytic efficiency to 1.07 × 10<SUP>4</SUP> M<SUP>–1</SUP> s<SUP>–1</SUP>. The enthalpy of in situ mineralization, the mechanism underlying the CO<SUB>2</SUB> absorption process, and the formation of an aggregated composition of CaCO<SUB>3</SUB> were examined using calorimetric, NMR, and X-ray diffraction techniques, respectively. The crystal formation depended crucially on the mineralization process involving the anions of the OMC precursors. The CaO-based sorbents derived from the CaCO<SUB>3</SUB> polymorphs shows good CO<SUB>2</SUB> capture capacity on combustion process, and the consecutive re-formation–regeneration cycles of the CaO sorbents followed the trend aragonite > vaterite > calcite. Hence, the MDEA–OMC–bCA system offers a promising method for transitioning between CaCO<SUB>3</SUB> polymorphs.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2014/jpccck.2014.118.issue-31/jp503448y/production/images/medium/jp-2014-03448y_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp503448y'>ACS Electronic Supporting Info</A></P>

Carbonic Anhydrase Promotes the Absorption Rate of CO₂ in Post-Combustion Processes

Vinoba, Mari,Bhagiyalakshmi, Margandan,Grace, Andrews Nirmala,Kim, Dae Hoon,Yoon, Yeoil,Nam, Sung Chan,Baek, Il Hyun,Jeong, Soon Kwan American Chemical Society 2013 The journal of physical chemistry. B, Condensed ma Vol.117 No.18

<P>The rate of carbon dioxide (CO<SUB>2</SUB>) absorption by monoethanol amine (MEA), diethanol amine (DEA), <I>N</I>-methyl-2,2′-iminodiethanol (MDEA), and 2-amino-2-methyl 1-propanol (AMP) solutions was found to be enhanced by the addition of bovine carbonic anhydrase (CA), has been investigated using a vapor–liquid equilibrium (VLE) device. The enthalpy (−Δ<I>H</I><SUB>abs</SUB>) of CO<SUB>2</SUB> absorption and the absorption capacities of aqueous amines were measured in the presence and/or absence of CA enzyme via differential reaction calorimeter (DRC). The reaction temperature (Δ<I>T</I>) under adiabatic conditions was determined based on the DRC analysis. Bicarbonate and carbamate species formation mechanisms were elucidated by <SUP>1</SUP>H and <SUP>13</SUP>C NMR spectral analysis. The overall CO<SUB>2</SUB> absorption rate (flux) and rate constant (<I>k</I><SUB>app</SUB>) followed the order MEA > DEA > AMP > MDEA in the absence or presence of CA. Hydration of CO<SUB>2</SUB> by MDEA in the presence of CA directly produced bicarbonate, whereas AMP produced unstable carbamate intermediate, then underwent hydrolytic reaction and converted to bicarbonate. The MDEA > AMP > DEA > MEA reverse ordering of the enhanced CO<SUB>2</SUB> flux and <I>k</I><SUB>app</SUB> in the presence of CA was due to bicarbonate formation by the tertiary and sterically hindered amines. Thus, CA increased the rate of CO<SUB>2</SUB> absorption by MDEA by a factor of 3 relative to the rate of absorption by MDEA alone. The thermal effects suggested that CA yielded a higher activity at 40 °C.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpcbfk/2013/jpcbfk.2013.117.issue-18/jp401622c/production/images/medium/jp-2013-01622c_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp401622c'>ACS Electronic Supporting Info</A></P>

CO₂ Absorption and Sequestration as Various Polymorphs of CaCO₃ Using Sterically Hindered Amine

Vinoba, Mari,Bhagiyalakshmi, Margandan,Grace, Andrews Nirmala,Chu, Dae Hyun,Nam, Sung Chan,Yoon, Yeoil,Yoon, Sung Ho,Jeong, Soon Kwan American Chemical Society 2013 Langmuir Vol.29 No.50

<P>One aspect of the attempt to restrain global warming is the reduction of the levels of atmospheric CO<SUB>2</SUB> produced by fossil fuel power systems. This study attempted to develop a method that reduces CO<SUB>2</SUB> emissions by investigating the absorption of CO<SUB>2</SUB> into sterically hindered amine 2-amino-2-methyl-1-propanol (AMP), the acceleration of the absorption rate by using the enzyme carbonic anhydrase (CA), and the conversion of the absorption product to stable carbonates. CO<SUB>2</SUB> absorbed by AMP is converted via a zwitterion mechanism to bicarbonate species; the presence of these anions was confirmed with <SUP>1</SUP>H and <SUP>13</SUP>C NMR spectral analysis. The catalytic efficiency (<I>k</I><SUB>cat</SUB>/<I>K</I><SUB>m</SUB>), CO<SUB>2</SUB> absorption capacities, and enthalpy changes (Δ<I>H</I><SUB>abs</SUB>) of aqueous AMP in the presence or absence of CA were found to be 2.61 × 10<SUP>6</SUP> or 1.35 × 10<SUP>2</SUP> M<SUP>–1</SUP> s<SUP>–1</SUP>, 0.97 or 0.96 mol/mol, and −69 or −67 kJ/mol, respectively. The carbonation of AMP-absorbed CO<SUB>2</SUB> was performed by using various Ca<SUP>2+</SUP> sources, viz., CaCl<SUB>2</SUB> (CAC), Ca(OOCCH<SUB>3</SUB>)<SUB>2</SUB> (CAA), and Ca(OOCCH<SUB>2</SUB>CH<SUB>3</SUB>)<SUB>2</SUB> (CAP), to obtain various polymorphs of CaCO<SUB>3</SUB>. The yields of CaCO<SUB>3</SUB> from the Ca<SUP>2+</SUP> sources were found in the order CAP > CAA > CAC as a result of the effects of the corresponding anions. CAC produces pure rhombohedral calcite, and CAA and CAP produce the unusual phase transformation of calcite to spherical vaterite crystals. Thus, AMP in combination with CAA and CAP can be used as a CO<SUB>2</SUB> absorbent and buffering agent for the sequestration of CO<SUB>2</SUB> in porous CaCO<SUB>3</SUB>.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2013/langd5.2013.29.issue-50/la403671y/production/images/medium/la-2013-03671y_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la403671y'>ACS Electronic Supporting Info</A></P>