scholarly journals Alkali-catalyzed production of biodiesel from waste frying oils

2009 ◽  
Vol 74 (8-9) ◽  
pp. 993-1007 ◽  
Author(s):  
Zlatica Predojevic ◽  
Biljana Skrbic
Keyword(s):  
Methyl Esters ◽  
Chemical Properties ◽  
Weight Ratio ◽  
Molar Ratio ◽  
Physical And Chemical Properties ◽  
Reaction Parameters ◽  
Waste Frying Oil ◽  
The Mean ◽  
Physical And Chemical ◽  
And Chemical Properties

The effects of the transesterification parameters on the yield and quality of the methyl esters (MEs) produced from waste frying oil (WFO) were investigated. A two-step alkali transesterification reaction followed by silica gel purification step was applied. The investigated reaction parameters were the methanol/oil molar ratio (6:1 and 9:1), the catalyst/oil weight ratio (1.0 and 1.5 mass %) and the type of catalyst (NaOH and KOH). The physical and chemical properties of the employed feedstock and the obtained biodiesel were determined in order to investigate the effects of both the properties of the WFO and the reaction parameters on the characteristics and yields of the product. It was found that the properties of the feedstock had a determinant effect on the physical and chemical properties of the MEs, as the majority of them did not differ significantly under the studied reaction parameters. However, the reaction parameters influenced the yields of the product. Higher yields were obtained with a 1.0 than with a 1.5 mass % catalyst to oil ratio. The increasing yield with decreasing catalyst/oil ratio was more pronounced with NaOH (9.15-14.35 %) than with KOH (2.84-6.45 %). When KOH was used as the catalyst, the yields were always higher (the mean yield was 94.86 %) in comparison to those obtained with NaOH (the mean was 84.28 %). Furthermore, the efficiency of KOH in conversion of WFO to purified MEs in comparison to NaOH was even more pronounced in the case of the higher methanol/oil ratio, i.e., for the 9:1 methanol/ oil ratio, the yield increase with KOH was about 2 times higher than the yield with NaOH, regardless of the applied catalyst/oil ratio.

scholarly journals Transesterification of linoleic and oleic sunflower oils to biodiesel using CaO as a solid base catalyst

2012 ◽  
Vol 77 (6) ◽  
pp. 815-832 ◽  
Author(s):  
Zlatica Predojevic ◽  
Biljana Skrbic ◽  
Natasa Djurisic-Mladenovic
Keyword(s):  
Iodine Value ◽  
Chemical Properties ◽  
Acid Methyl Ester ◽  
Acid Value ◽  
Molar Ratio ◽  
Physical And Chemical Properties ◽  
Reaction Parameters ◽  
Sunflower Oils ◽  
Physical And Chemical ◽  
And Chemical Properties

The purpose of this work is to characterize biodiesel (i.e. methyl esters, MEs) produced from linoleic and oleic sunflower oils (LSO and OSO, respectively) by alkali transesterification with methanol and CaO as a heterogeneous catalyst under different reaction parameters. The parameters investigated were the methanol/oil molar ratio (4.5:1, 6:1, 7.5:1, 9:1 and 12:1) and the mass ratio of CaO to oil (2% and 3%). The physical and chemical properties of the feedstocks and MEs, like density at 15oC, kinematic viscosity at 40oC, acid value, iodine value, saponification value, cetane index, fatty acid (methyl ester) composition, were determined in order to investigate the effects of LSO and OSO properties and reaction parameters on the product characteristics, yields and purity. The properties of feedstock had decisive effect on the physical and chemical properties of MEs as majority of them did not differ significantly under studied reaction conditions. The MEs produced generally met the criteria required for commercial biodiesel; in fact, the only exception was in the case of iodine value of ME produced from LSO. The product yields only slightly changed with the applied conditions; the highest yield (99.22%) was obtained for ME-LSO produced at 6 mol% methanol to oil ratio, while the lowest one (93.20%) was for ME-OSO produced under the lowest methanol/oil molar ratio (4.5:1). The applied catalyst amounts had similar influence on the oil conversion to biodiesel. The yields of ME-LSOs were in general somewhat higher than those obtained for ME-OSOs under the same conditions, which was attributed to the influence of the respective feedstocks' acid value and viscosity.

scholarly journals Synthesis of monoketo and monohydroxy eicosanoic acids and esters with substituents at odd-numbered (3-13) carbons

2002 ◽  
Vol 67 (7) ◽  
pp. 473-480 ◽  
Author(s):  
Hulya Çelik
Keyword(s):  
Nmr Spectroscopy ◽  
High Purity ◽  
1H Nmr Spectroscopy ◽  
Methyl Esters ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Keto Acids ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
And Chemical Properties

In this study, monoketo and monohydroxy eicosanoic acids and their methyl esters with the position of the substituent on odd numbered carbon atoms from 3 to 13 were synthesized with high purity. Furthermore, the semicarbazone and anilide derivatives of the obtained keto acids were prepared. They were characterized by TLC, IR and 1H-NMR spectroscopy and their physical and chemical properties were established.

The comparison of rapeseeds’ oils from hybrid and open-pollinated varieties by their heating values in the aspect of Diesel utilization

2010 ◽  
Vol 1 (1) ◽  
pp. 157-161
Author(s):  
E. Sarkozi ◽  
L. Janosi
Keyword(s):  
Energy Content ◽  
Methyl Esters ◽  
Research Work ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Heating Value ◽  
Biofuel Feedstock ◽  
Physical And Chemical ◽  
And Chemical Properties

The rape is one of the suitable plant species for biofuel feedstock in Hungary. Currently there are over 100 admitted rape sorts recorded in Hungary and their oils’ application as biodiesel proposes new aspects of evaluation. From references it is noticeable that there are differences in the physical and chemical properties of the various rape sorts’ oils and rapeseed-methyl-esters. Our aim is to analyze the differences in the quality of the various rape sorts’ oils and to determine the most appropriate rape sort in the viewpoint of technical utilization. In the course of present research work we have measured the heating values of 21 various rapesorts’ oils -12 from open-pollinated varieties and 9 from hybrids- and examined the differences between them. The outcome values dispersed in the range of the heating values found in the references, but the differences between them are less then the predicted, the variance and the coefficient of variation are reasonably slight, so the examined rape sorts’ oils are similar in the viewpoint of the heating value. Furthermore, the energy content of the rapeseed oils is independent of the type (hybrid or open-pollinated variety) of the plant.

scholarly journals Physical and Chemical Properties of Biodiesel Obtained from Amazon Sailfin Catfish (Pterygoplichthys pardalis) Biomass Oil

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
F. Anguebes-Franseschi ◽  
A. Bassam ◽  
M. Abatal ◽  
O. May Tzuc ◽  
C. Aguilar-Ucán ◽  
...  
Keyword(s):  
Atomic Absorption ◽  
Methyl Esters ◽  
Ecological Impact ◽  
Chemical Properties ◽  
Absorption Spectrometry ◽  
Raw Material ◽  
Gas Chromatography Mass Spectrometry ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Amazon sailfin catfish (Pterygoplichthys pardalis) is considered one of the greatest threats to the biodiversity of continental aquatic systems, causing serious economic and environmental problems in the regions. In this work, the production of biodiesel from Amazon sailfin catfish biomass oil is studied. The physical and chemical properties of biofuel produced were evaluated under the specifications of the European standard EN-14214 by using gas chromatography-mass spectrometry, infrared spectroscopy, and atomic absorption spectrometry analyses. The results show that the biodiesel complies with all the specifications of the standard, except the content of polyunsaturated methyl esters. The yields obtained from oil and biodiesel were 9.67 and 90.71% (m/m), respectively. The methyl ester concentrations study identified 17 components where 47.003% m/m corresponded to methyl esters with saturated chains, whereas 34.394% m/m was attributed to monosaturated methyl esters and the remaining (18.624% m/m) to polysaturated methyl esters. Finally, mineral analysis by atomic absorption showed the absence of heavy metals Cd, Ni, and Pb, as well as low concentrations of Ni, Fe, Cu, and Zn, demonstrating that the quality of the fuel is not compromised. The study indicates the feasibility of manufacturing biodiesel using Amazon sailfin catfish biomass oil as a low-cost raw material. It represents an environmental option to mitigate a global problem of atmospheric pollution, and at the same time, it shows a commercial alternative to reduce the ecological impact caused by this fish in the diverse ecosystems to which it has spread. In addition, the great adaptability of this fish provides the possibility of a profitable process to have very high rates of reproduction and growth, allowing the generation of large amounts of biomass for the production of biodiesel.

scholarly journals The cloudbow of planet Earth observed in polarisation

2020 ◽  
Vol 639 ◽  
pp. A89
Author(s):  
Michael F. Sterzik ◽  
Stefano Bagnulo ◽  
Claudia Emde ◽  
Mihail Manev
Keyword(s):  
Liquid Water ◽  
Chemical Properties ◽  
Phase Curve ◽  
Physical And Chemical Properties ◽  
Molecular Scattering ◽  
Droplet Sizes ◽  
The Mean ◽  
Physical And Chemical ◽  
Phase Angles ◽  
And Chemical Properties

Context. Scattering processes in the atmospheres of planets cause characteristic features that can be particularly well observed in polarisation. For planet Earth, both molecular scattering (Rayleigh) and scattering by small particles (Mie) imprint specific signatures in its phase curve. Polarised phase curves allow us to infer physical and chemical properties of the atmosphere like the composition of the gaseous and liquid components, droplet sizes, and refraction indices. Aims. An unequivocal prediction of a liquid-water-loaded atmosphere is the existence of a rainbow feature at a scattering angle of around 138–144°. Earthshine allows us to observe the primary rainbow in linear polarisation. Methods. We observed polarisation spectra of Earthshine using FORS2 at the Very Large Telescope for phase angles from 33° to 65° (Sun–Earth–Moon angle). The spectra were used to derive the degree of polarisation in the B, V, R, and I passbands and the phase curve from 33° to 136°. The new observations extend to the smallest phases that can be observed from the ground. Results. The degree of polarisation of planet Earth is increasing for decreasing phase angles downwards of 45° in the B, V, R, and I passbands. From comparison of the phase curve observed with models of an Earth-type atmosphere we are able to determine the refractive index of water and to constrain the mean water droplet sizes to 6−7μm. Furthermore, we can retrieve the mean cloud fraction of liquid water clouds to 0.3, and the mean optical depth of the water clouds to values between 10 and 20. Conclusions. Our observations allow us to discern two fundamentally different scattering mechanisms of the atmosphere of planet Earth: molecular and particle scattering. The physical and chemical properties can be retrieved with high fidelity through suitable inversion of the phase curve. Observations of polarimetric phase curves of planets beyond the Solar System shall be extremely valuable for a thorough characterisation of their atmospheres.

scholarly journals The improved photostability of naproxen in the inclusion complex with 2-hydroxypropyl-β-cyclodextrin

2015 ◽  
Vol 69 (4) ◽  
pp. 361-370 ◽  
Author(s):  
Snezana Ilic-Stojanovic ◽  
Vesna Nikolic ◽  
Ljubisa Nikolic ◽  
Aleksandar Zdravkovic ◽  
Agnes Kapor ◽  
...  
Keyword(s):  
Inclusion Complex ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Physical And Chemical Properties ◽  
Ftir Analysis ◽  
Molecular Inclusion ◽  
Co Precipitation ◽  
Physical And Chemical ◽  
And Chemical Properties

The aim of this work was the preparation of the inclusion complex of naproxen with 2-hydroxypropyl-?-cyclodextrin (HP-?-CD) in order to improve the physical and chemical properties of naproxen. The molecular inclusion complexes of naproxen with HP-?-CD were prepared by using the co-precipitation method in the solid state with the molar ratio of 1:1. The structure of the obtained complex was characterized by using FTIR, 1H NMR, UV-Vis and XRD methods. The testing of naproxen photostability by the UV-Vis method indicated the degradation to aromatic ketone, 2-acetyl-6-methoxynaphthalene. FTIR analysis showed that the degradation started 15 days after the exposure of naproxen to daylight while the inclusion complex of naproxen: 2-hydroxypropyl-?-cyclodextrin was photostable for a period of 30 days.

Influence of Physical and Chemical Properties of Two Biodiesel Fuels on Performance, Combustion and Exhaust Emission Characteristics in a DI-CI Engine

2008 ◽  
Author(s):  
V. Pulagala Rao ◽  
Basava V. A. Rao
Keyword(s):  
Methyl Esters ◽  
Chemical Properties ◽  
Premixed Combustion ◽  
Physical And Chemical Properties ◽  
No Emission ◽  
Full Load ◽  
Ci Engine ◽  
Peak Pressures ◽  
Physical And Chemical ◽  
And Chemical Properties

The purpose of this study is to examine the influence of biodiesel (BD) fuel properties on different characteristics of the engine and to compare with the baseline petroleum diesel (PD) fuel. This study consists of two parts, first one is biodiesel characterization and the second one is testing in the engine. Two BD fuels namely, the medium chain (C6–C24) coconut oil methyl ester (COME) and the long chain (C16–C18) sesame seed oil methyl ester (SSME) were selected. It is observed that, the physical and chemical properties such as viscosity, density, bulk modulus, calorific value, C/H ratio, and iodine value of SSME are higher than that of COME, while the cetane number, saturation% and oxygen% of the COME is higher than that of SSME. Experiments were conducted in a naturally aspirated, single cylinder, four-stroke, stationary, water cooled, constant rpm (1500), in-line (pump-high pressure tube-fuel injector) direct injection compression ignition (DI–CI) engine with COME, SSME (with and without preheating), and PD as fuels. The performance was evaluated in terms of fuel consumption (FC), brake specific energy consumption (BSEC), and thermal efficiency (BTE). Except for COME at full load, the BTE of the esters over all load ranges were less than that of PD fuel. Also, a significant improvement in BTE was observed, when the SSME is tested at PD’s viscosity by using preheating technique. At full load, the BSFC of COME and SSME are increased by 16.61% and 18.24% respectively. The minimum BSEC (at full load) of COME is decreased by 1.3% and while that of SSME is increased by 4.5%, as compared to that of PD fuel. The full load peak pressures for COME, SSME and PD fuel are 63.8 bar, 65.8 bar, and 62.9 bar respectively. The high peak pressures of the methyl esters are probably due to dynamic injection advance, caused by their higher bulk modulus. The net heat release rate (HRR) and cumulative heat release (CHR) were calculated from the acquired data. The results show that, at all loads there is a slight increase in peak HRR for COME and large increase in peak HRR for SSME against PD fuel. The higher values of peak HRR indicate better premixed combustion with the methyl esters. However, the peak HRR for preheated SSME (SSME_H) decreases due to late injection and faster evaporation of the fuel. It was observed that, at full load the nitric oxide (NO) emission of SSME is increased by 12.9%, while that of COME is decreased by 13.8% as compared to that of PD fuel. The smoke is increasing linearly with the fuels ‘C/H’ ratio regardless of their molecular structure. The HC emissions of both the esters are very low and are reduced by up to 73%, as compared PD. Also, there is a significant reduction in all exhaust emissions, and in particular the NO emission is observed with preheated SSME, due to change in premixed combustion phase.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

Sign in / Sign up

Export Citation Format

Share Document