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[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Foreword 1. Prosperity Lost 2. The Age of Irresponsibility 3. Redefining Prosperity 4. The Dilemma of Growth 5. The Myth of Decoupling 6. The 'Iron Cage' of Consumerism 7. Keynesianism and the 'Green New Deal' 8. Ecological Macro-Economics 9. Flourishing - within Limits 10. Governance for Prosperity 11. The Transition to a Sustainable Economy 12. A Lasting Prosperity Appendices References Endnotes

Prosperity without growth : economics for a finite planet

Biodiesel is produced by the transesterification of oil triglycerides with methanol or ethanol, in the presence of a homogeneous or heterogeneous catalyst. This study aims to report the results of the transesterification of sunflower oil with methanol to produce biodiesel using CaO nanoparticles supported on NaX zeolite as catalyst. The effect of the CaO nanoparticles concentration on the NaX zeolite surface was studied in the range of 5−25 wt %. The transesterification reaction was carried out at reflux temperature of methanol, atmospheric pressure, a reaction time of 6 h, and with a 6:1 molar ratio of methanol to sunflower oil. Catalyst characterization was carried out by X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. It was concluded that methyl esters content is highly influenced by basicity and that the best catalyst was the one holding 16 wt % CaO nanoparticles. The produced biodiesel was 93.5% methyl esters and was found to fulfill the specifications of Europ...

Preparation and Characterization of CaO Nanoparticles/NaX Zeolite Catalysts for the Transesterification of Sunflower Oil

The world is confronted with the twin crises of fossil fuel depletion and environmental degradation. The indiscriminate extraction and consumption of fossil fuels have led to a reduction in petroleum reserves. Petroleum based fuels are obtained from limited reserves. These finite reserves are highly concentrated in certain region of the world. Therefore, those countries not having these resources are facing a foreign exchange crisis, mainly due to the import of crude petroleum oil. Hence it is necessary to look for alternative fuels, which can be produced from materials available within the country. Although vegetative oils can be fuel for diesel engines, but their high viscosities, low volatilities and poor cold flow properties have led to the investigation of its various derivatives. Among the different possible sources, fatty acid methyl esters, known as Biodiesel fuel derived from triglycerides (vegetable oil and animal fates) by transesterification with methanol, present the promising alternative substitute to diesel fuels and have received the most attention now a day. The main advantages of using Biodiesel are its renewability, better quality exhaust gas emission, its biodegradability and the organic carbon present in it is photosynthetic in origin. It does not contribute to a rise in the level of carbon dioxide in the atmosphere and consequently to the green house effect. This paper reviews the source of production and characterization of vegetable oils and their methyl ester as the substitute of the petroleum fuel and future possibilities of Biodiesel production.

Biodiesel production through the use of different sources and characterization of oils and their esters as the substitute of diesel: A review

Microalgal phospholipid bilayer contributes to the molar excesses of methanol and high acid concentration required in reactive extraction to achieve high fatty acid methyl ester (FAME) yield. This study reports an investigation into the effects of pre-soaking Nannochloropsis occulata in methanol at 600:1 and 1000:1 methanol to oil molar ratios prior to acid-catalyzed in situ transesterification at 8.5:1 and 15:1 H2SO4 to oil molar ratios on the FAME yield. The results showed that the pre-soaked Nannochloropsis occulata produced a higher FAME yield at the two tested methanol to oil molar ratios and acid concentrations than the un-soaked, resulting in a reduction in methanol volume and acid concentration. A maximum FAME yield of 98.4% ± 1.3% was obtained for the pre-soaked Nannochloropsis occulata at 1000:1 methanol to oil molar ratio and 15:1 H2SO4 to oil molar ratio. Both the phosphorus mass balance and conversion of the isolated phospholipids into FAME revealed that pre-soaking solubilizes the phospholipid bilayer to some degree, and contributes to an increased FAME yield.

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Effect of Soaking Pre-Treatment on Reactive Extraction/ in situ Transesterification of Nannochloropsis occulata for Biodiesel Production

Preheated Schizochytrium sp. raw microalgae oil (MAO) was evaluated as a fuel in a single-cylinder four-stroke diesel engine to produce a comparative study of MAO and diesel oil (DO) critical parameters. In particular, brake power, brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), in-cylinder pressure (CP), exhaust gas temperature (EGT), both nitrogen oxides (NOx) and carbon monoxide (CO) emissions were investigated. Additionally, an engine durability test for longevity was undertaken over a 30-h period, using raw MAO as the fuel. The study demonstrated that the preheated MAO could be successfully used in a diesel engine smoothly. The use of MAO reduced the engine brake power by 26% and increased brake-specific fuel consumption by 20%. The most significant finding from this research study is that there was a significant reduction in NOx and CO emission by 42% and 60% when using raw MAO, respectively. Therefore, these findings demonstrate that algae oil is a highly credible fuel for use in diesel engines and offers a promising solution to diesel engine emissions.

https://www.mdpi.com/2504-3900/58/1/4/pdf

Performance, Emissions and Durability Studies on Diesel Engine fuelled with a Preheated Raw Microalgal Oil

Biodiesel has recently gained popularity due to its environmental issues and the fact that it is generated from renewable resources. However, the cost of the synthesis of biodiesel is the major impediment to commercialization. The utilization of leftover cooking oils as raw material, the adaptation of a continuous transesterification process, and the use of cheap catalysts are the major possibilities for investigating the cost of biodiesel. In this work, a dolomite catalyst was prepared from natural dolomite rocks and used for the evaluation of continuous transesterification of biodiesel from oleic acid as a model compound of waste cooking oil (WCO). The dolomite catalyst was prepared by activation under vacuum at a surface area of 34.5 m2/g. The characterization tests showed good thermal stability of the catalyst and evolution of the CaO and MgO compounds at high concentrations. A kinetic study was conducted to obtain kinetic parameters of catalytic transesterification of the WCO. The kinetic experiments were carried out at 298K-333K, and residence time up to 80 min. The results presented that the catalytic transesterification is the first-order reaction, and the activation energy was 43 kJ/mol. The oscillatory baffled reactor (OBR) was used to evaluate the dolomite catalyst for the continuous production of biodiesel via transesterification. The evaluation study was conducted at a methanol: oil mole ratio of 6:1 and the effect of different operation variables on oleic acid conversion to biodiesel was studied. These variables were temperature (323K, 333K, and 343K), residence times (5-40 min), the amplitude of oscillation (2-8 mm), and frequency of oscillation (1, 2, 3, 4 and 4.3 Hz). The results showed an outstanding performance and stable activity of the dolomite catalyst as a conversion of 96% was obtained at 333K, 4.3 Hz, 8 mm amplitude, and 40 min residence time. This article is protected by copyright. All rights reserved. 

Use of Dolomite Catalyst in Biodiesel Production via Transesterification of Waste Cooking Oil in Oscillatory Baffled Reactor

Intensification of epoxidation of vegetable oils using a continuous mesoscale oscillatory baffled reactor

There are numerous potential benefits of conducting chemical reactions in the absence of solvent. For instance, the risk of environmental release of the solvent is eliminated and there is the potential for intensification via increased reaction rates reducing the required reactor volume. It was previously shown that two configurations of the mesoscale oscillatory baffled reactor (heat pipe and jacketed) could address the challenge of performing exothermic reactions without a solvent, by removing or spreading out the heat released. This could lead to a new approach in green chemistry. Here, this concept was extended to reaction kinetics screening from the same exothermic imination reaction conducted without a solvent. The effects of up to three operating variables (residence time, reactant molar ratio and temperature) were screened in a single flow experiment. It was found that both reactor configurations were able to obtain the Arrhenius kinetic parameters: activation energies of 103.98 ± 3.79 kJ/mol and 98.11 ± 1.55 kJ/mol, respectively, for the two imine synthesis steps. This demonstrated that meaningful data could be obtained, even though the solventless reaction medium was changing as a function of the reaction. Other benefits of this green chemistry approach include: high reaction rates/throughputs, reduced preparation time and reduced downstream purification requirements.

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Adam Harvey

Papers

Effect of Soaking Pre-Treatment on Reactive Extraction/ in situ Transesterification of Nannochloropsis occulata for Biodiesel Production

Performance, Emissions and Durability Studies on Diesel Engine fuelled with a Preheated Raw Microalgal Oil

Use of Dolomite Catalyst in Biodiesel Production via Transesterification of Waste Cooking Oil in Oscillatory Baffled Reactor

Intensification of epoxidation of vegetable oils using a continuous mesoscale oscillatory baffled reactor

The mesoscale oscillatory baffled reactor facilitates intensified kinetics screening when the solvent is removed