scholarly journals Purification of Methyl Acetate/Water Mixtures from Chemical Interesterification of Vegetable Oils by Pervaporation

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 775
Author(s):  
Abraham Casas ◽  
Ángel Pérez ◽  
María Jesús Ramos
Keyword(s):  
Methyl Acetate ◽  
Operating Temperature ◽  
Operating Conditions ◽  
Biodiesel Production ◽  
Design Parameters ◽  
Chemical Interesterification ◽  
Permeate Flux ◽  
A Value ◽  
Pervaporation Membrane ◽  
Hydrophilic Character

Biodiesel production through chemical interesterification of triglycerides requires an excess of methyl acetate that must be recovered once the reaction is finished and the catalyst is neutralized. The present study concerns with the purification of methyl acetate by pervaporation. PERVAP 2201 was chosen as pervaporation membrane due to its high hydrophilic character that makes it suitable for the elimination of water in methyl acetate. Runs were started from concentrations in the feed of 2–8 wt.% of water and working temperatures close to the boiling point of methyl acetate (50, 60, and 70 °C), to get the main design parameters, i.e., permeate flux and selectivity. High temperature favored the permeate flux without compromising the selectivity. However, the flux declines significantly when water contained in the feed is below 2 wt.%. This implies that pervaporation should be used, only to decrease the water content to a value lower than in the azeotrope (2.3% by weight). A solution-diffusion model relating the flux of the permeating compound with the activity of the compound in the feed and the operating temperature has been proposed. The model obtained can be used in the design of the pervaporation stage, thus allowing to know the permeate flux for the different operating conditions.

scholarly journals Box-Behnken Design for Optimization on Biodiesel Production from Palm Oil and Methyl Acetate using Ultrasound Assisted Interesterification Method

2021 ◽  
Author(s):  
Mahfud Mahfud ◽  
Ansori Ansori
Keyword(s):  
Palm Oil ◽  
Energy Demand ◽  
Alternative Energy ◽  
Methyl Acetate ◽  
Catalyst Concentration ◽  
Separation Process ◽  
Operating Conditions ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Box Behnken Design

Energy demand is currently increasing in line with technological and economic developments, but not accompanied by an increase in energy reserves. So we need another alternative energy that can be renewed, namely biodiesel. Biodiesel has been produced commercially through the transesterification from vegetable oil with methanol using catalyst that produces esters and glycerol. The formation of glycerol which is by-product can reduce its economic value, so it needs to be done the separation process. Therefore, a new route is proposed in this study, namely the interesterification reaction (non-alcoholic route) using methyl acetate as an alkyl group supplier and potassium methoxide catalyst. The superiority of the product produced by the interesterification reaction is biodiesel with triacetin byproducts which have an economical value and can be added to biodiesel formulations because of their solubility so that no side product separation process is needed. To increase the yield of biodiesel and the interesterification rate, the ultrasound method was used in this study. To optimize the factors that affect the interesterification reaction (molar ratio of methyl acetate to oil, catalyst concentration, temperature, and interesterification time), the Box-Behnken design (BBD) is used. Optimal operating conditions to produce the yields of biodiesel of 98.64 % are at molar ratio of methyl acetate to palm oil of 18.74, catalyst concentration of 1.24 %, temperature of 57.84 °C, and interesterification time of 12.69 minutes.

scholarly journals CHEMICAL INTERESTERIFICATION OF COTTON OIL WITH METHYL ACETATE ASSISTED BY ULTRASOUND FOR BIODIESEL PRODUCTION

2018 ◽  
Vol 35 (3) ◽  
pp. 1005-1018 ◽  
Author(s):  
Aldo M. Medeiros ◽  
Ênio R. M. Santos ◽  
Saulo H. G. Azevedo ◽  
Anderson A. Jesus ◽  
Humberto N. M. Oliveira ◽  
...  
Keyword(s):  
Methyl Acetate ◽  
Biodiesel Production ◽  
Chemical Interesterification ◽  
Cotton Oil

Experimental Performance Comparison of a Single Cell and Multi-Cell Stack of High Temperature PEM Fuel Cell Prototype

2010 ◽  
Author(s):  
Susanta K. Das ◽  
Etim U. Ubong ◽  
Antonio Reis ◽  
K. Joel Berry
Keyword(s):  
High Temperature ◽  
Fuel Cell ◽  
Single Cell ◽  
Operating Temperature ◽  
Operating Conditions ◽  
Experimental Results ◽  
Design Parameters ◽  
Fuel Cell Stack ◽  
Current Voltage ◽  
Current Voltage Characteristics

In this study, we experimentally studied our newly designed and built single cell and multi-cell high temperature (140°C∼180°C) polymer electrolyte membrane (HTPEM) fuel cell stack prototype at different operating conditions to investigate the effects of operating temperature, pressure and CO concentration on the cell performance. In particular, the effects of these parameters on the current-voltage characteristics of the fuel cell stack are investigated extensively. Experimental results obtained from both the single cell and multi-cell stack with high temperature PBI-based membrane show that the high CO tolerance at high operating temperature of HTPEM fuel cell stack makes it possible to feed the reformate gas directly from the reformer without further CO removal. In order to develop design parameters for fuel reformer, experimental data of this type would be very useful. The experimental results revealed the fact that a fuel reformer is a consumer of heat and water, and the HTPEM fuel cell stacks are a producer of heat and water. Therefore, the integration of the fuel cell stack and the reformer is expected to improve the entire system’s performance and efficiency. The results obtained from this study showed significant variations in current-voltage characteristics of HTPEM fuel cell stack at different temperatures with different CO poisoning rates. The results are promising to understand the overall system performance development strategy of HTPEM fuel cell in terms of current-voltage characteristics while fed with on-site reformate with different CO ratios in the anode fuel stream.

Dynamic modeling of fouling over multiple biofuel production cycles in a membrane reactor

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Thien An Huynh ◽  
Edwin Zondervan
Keyword(s):  
Membrane Fouling ◽  
Membrane Reactor ◽  
Membrane Filtration ◽  
Reaction System ◽  
Operating Conditions ◽  
Biodiesel Production ◽  
Biofuel Production ◽  
Cyclic Behavior ◽  
Permeate Flux ◽  
Production Cycles

Abstract In this paper, a novel mathematical model that combines a membrane filtration model, component balances and reaction kinetics models for an intensified separation-reaction process in membrane reactor producing biofuels was developed. A unique feature is that the proposed model can capture the dynamics of membrane fouling as function of both reversible and irreversible fouling; which leads to cyclic behavior. Fouling leads to the decline of the reactor productivity. With an appropriate fouling-model, the operational strategy can be optimized. In the case study of biodiesel production, the developed model was validated with experimental data. The model was in good agreement with the data, where R-squared are 0.96 for the permeate flux and 0.95 for the biodiesel yield. From a further analysis, the efficiency of membrane reaction system in term of productivity can be significantly improved by changing the backwashing frequency under specific operating conditions. As the backwashing frequency increased eight times, the biodiesel yield increased to more than two to three times before the permeate flux dropped under a predetermined limit due to the increase of irreversible membrane fouling.

scholarly journals Performance Analysis of Natural-Refrigerants-Based Vortex Tube Expansion Refrigeration Cycles

2013 ◽  
Vol 06 (2) ◽  
Keyword(s):  
Performance Improvement ◽  
Vortex Tube ◽  
Operating Temperature ◽  
Operating Conditions ◽  
Design Parameters ◽  
Refrigeration Cycle ◽  
Expansion Valve ◽  
Tube Expansion ◽  
Vapour Compression ◽  
Cycle Temperature

The energetic analyses and comparison of three natural refrigerants, ammonia, propane and isobutane based vapour compression refrigeration cycles are presented in this article using a vortex tube as an expansion device. A simple thermodynamic model has been used for analyses of two vortex tube expansion refrigeration cycle layouts based on the Maurer model (1999) and the Keller model (1997). Effects of various operating and design parameters of the COP improvement using vortex tube instead of expansion valve are presented. Results show that the COP improvement over basic expansion cycle increases with increase in cycle temperature lift for both cycle layouts. The COP improvement of CYC1 can be realized for certain operating temperature combinations. Effects of design parameters on the performance improvement are negligible. Study shows that the COP improvement using vortex tube as an expansion device are dependent on the refrigerant varieties, operating conditions as well as cycle configurations. Using the vortex tube as an expansion device, isobutane yields a maximum COP improvement of 12.2% for CYC2 followed by propane (11.5% for CYC2), whereas ammonia yields negligible improvement for studies ranges.

Truck Tire Operating Temperatures on Flat and Curved Test Surfaces

2005 ◽  
Vol 33 (3) ◽  
pp. 156-178 ◽  
Author(s):  
T. J. LaClair ◽  
C. Zarak
Keyword(s):  
Flat Surface ◽  
Operating Temperature ◽  
Operating Conditions ◽  
Load Pressure ◽  
Truck Tire ◽  
Endurance Testing ◽  
Operating Temperatures ◽  
The Impact ◽  
Tread Rubber ◽  
Cylindrical Test

Abstract Operating temperature is critical to the endurance life of a tire. Fundamental differences between operations of a tire on a flat surface, as experienced in normal highway use, and on a cylindrical test drum may result in a substantially higher tire temperature in the latter case. Nonetheless, cylindrical road wheels are widely used in the industry for tire endurance testing. This paper discusses the important effects of surface curvature on truck tire endurance testing and highlights the impact that curvature has on tire operating temperature. Temperature measurements made during testing on flat and curved surfaces under a range of load, pressure and speed conditions are presented. New tires and re-treaded tires of the same casing construction were evaluated to determine the effect that the tread rubber and pattern have on operating temperatures on the flat and curved test surfaces. The results of this study are used to suggest conditions on a road wheel that provide highway-equivalent operating conditions for truck tire endurance testing.

scholarly journals Recovery of Anthocyanins and Monosaccharides from Grape Marc Extract by Nanofiltration Membranes

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2003
Author(s):  
Paul Muñoz ◽  
Karla Pérez ◽  
Alfredo Cassano ◽  
René Ruby-Figueroa
Keyword(s):  
Functional Foods ◽  
General Trend ◽  
Value Added ◽  
Operating Conditions ◽  
Permeate Flux ◽  
Ultrasound Assisted Extraction ◽  
Grape Marc ◽  
Assisted Extraction ◽  
The One ◽  
By Products

Wastewaters and by-products generated in the winemaking process are important and inexpensive sources of value-added compounds that can be potentially reused for the development of new products of commercial interest (i.e., functional foods). This research was undertaken in order to evaluate the potential of nanofiltration (NF) membranes in the recovery of anthocyanins and monosaccharides from a clarified Carménère grape marc obtained through a combination of ultrasound-assisted extraction and microfiltration. Three different flat-sheet nanofiltration (NF) membranes, covering the range of molecular weight cut-off (MWCO) from 150 to 800 Da, were evaluated for their productivity as well as for their rejection towards anthocyanins (malvidin-3-O-glucoside, malvidin 3-(acetyl)-glucoside, and malvidin 3-(coumaroyl)-glucoside) and sugars (glucose and fructose) in selected operating conditions. The selected membranes showed differences in their performance in terms of permeate flux and rejection of target compounds. The NFX membrane, with the lowest MWCO (150–300 Da), showed a lower flux decay in comparison to the other investigated membranes. All the membranes showed rejection higher than 99.42% for the quantified anthocyanins. Regarding sugars rejection, the NFX membrane showed the highest rejection for glucose and fructose (100 and 92.60%, respectively), whereas the NFW membrane (MWCO 300–500 Da) was the one with the lowest rejection for these compounds (80.57 and 71.62%, respectively). As a general trend, the tested membranes did not show a preferential rejection of anthocyanins over sugars. Therefore, all tested membranes were suitable for concentration purposes.

scholarly journals Enzymatic Transesterification of Waste Frying Oil from Local Restaurants in East Colombia Using a Combined Lipase System

2020 ◽  
Vol 10 (10) ◽  
pp. 3566
Author(s):  
Mary Angélica Ferreira Vela ◽  
Juan C. Acevedo-Páez ◽  
Nestor Urbina-Suárez ◽  
Yeily Adriana Rangel Basto ◽  
Ángel Darío González-Delgado
Keyword(s):  
Reaction Time ◽  
Methyl Esters ◽  
Enzyme Concentration ◽  
Operating Conditions ◽  
Frying Oil ◽  
Biodiesel Production ◽  
Optimum Operating ◽  
Waste Frying Oil ◽  
Production Chain ◽  
Enzymatic Transesterification

The search for innovation and biotechnological strategies in the biodiesel production chain have become a topic of interest for scientific community owing the importance of renewable energy sources. This work aimed to implement an enzymatic transesterification process to obtain biodiesel from waste frying oil (WFO). The transesterification was performed by varying reaction times (8 h, 12 h and 16 h), enzyme concentrations of lipase XX 25 split (14%, 16% and 18%), pH of reaction media (6, 7 and 8) and reaction temperature (35, 38 and 40 °C) with a fixed alcohol–oil molar ratio of 3:1. The optimum operating conditions were selected to quantify the amount of fatty acid methyl esters (FAMEs) generated. The highest biodiesel production was reached with an enzyme concentration of 14%, reaction time of 8 h, pH of 7 and temperature of 38 °C. It was estimated a FAMEs production of 42.86% for the selected experiment; however, best physicochemical characteristics of biodiesel were achieved with an enzyme concentration of 16% and reaction time of 8 h. Results suggested that enzymatic transesterification process was favorable because the amount of methyl esters obtained was similar to the content of fatty acids in the WFO.

scholarly journals Data-driven Modelling of Microfiltration Process with Embedded Static Mixer for Steepwater from Corn Starch Industry

2017 ◽  
Author(s):  
Laslo Šereš ◽  
Ljubica Dokić ◽  
Bojana Ikonić ◽  
Dragana Šoronja-Simović ◽  
Miljana Djordjević ◽  
...  
Keyword(s):  
Corn Starch ◽  
Desirability Function ◽  
Specific Energy Consumption ◽  
Cross Flow ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Static Mixer ◽  
Permeate Flux ◽  
Experimental Conditions ◽  
Starch Industry

Cross-flow microfiltration using ceramic tubular membrane was applied for treatment of steepwater from corn starch industry. Experiments are conducted according to the faced centered central composite design at three different transmembrane pressures (1, 2 and 3 bar) and cross-flow velocities (100, 150 and 200 L/h) with and without the usage of Kenics static mixer. For examination of the influence of the selected operating conditions at which usage of the static mixer is justified, a response surface methodology and desirability function approach were used. Obtained results showed improvement in the average permeate flux by using Kenics static mixer for 211 % to 269 % depending on experimental conditions when compared to the system without the static mixer. As a result of optimization, the best results considering flux improvement as well as reduction of specific energy consumption were obtained at low transmembrane pressure and lower feed cross-flow rates.

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