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1
Content available remote Eter dimetylowy : perspektywiczne paliwo do silników z zapłonem samoczynnym?
100%
Górski W. , Kulczycki A.
Przemysł Chemiczny
|
2009
|
tom T. 88, nr 3
222-227
2
Content available remote Koncepcja wymagań jakościowych do eteru dimetylowego (DME) stosowanego jako paliwo silnikowe
100%
Górski W. , Kęsik A. , Skolniak M.
Przemysł Chemiczny
|
2009
|
tom T. 88, nr 3
228-233
3
Content available Process simulation of dimethyl ether synthesis via methanol vapor phase dehydration
100%
Bai Z. , Ma H. , Zhang H. , Ying W. , Fang D.
Polish Journal of Chemical Technology
|
2013
|
tom Vol. 15, nr 2
122–127
EN
The production processes included catalytic dehydration of methanol in an adiabatic fixed-bed reactor and two columns product separations. In this study, the technological process for dimethyl ether (DME) synthesis is built on PRO/II platform based on the combined parameters of the reaction dynamic model for methanol dehydration reaction, the improved NRTL model of the liquid phase, the PR model of vapor phase. In order to validate the proposed model, the simulation results have been compared with the available data from a set of industrial production equipment with a production capacity of 200 000 tonnes per annum. A comparison between the calculated and measured results has proved that these results are satisfactory. The bed height and the volume of the catalytic bed are calculated aim at one million t/a DME yields and while taking account of high-purity DME production. After discussing the influence of feed stage location and reflux ratio for DME product purity, the suitable unit operation conditions are chosen. Accordingly, accurate process simulation results provide the basis and guidance for an improvement and development of the similar industrial device.
4
Content available remote Process simulation of dimethyl ether synthesis via methanol vapor phase dehydration
100%
Bai Z. , Ma H. , Zhang H. , Ying W. , Fang D.
Polish Journal of Chemical Technology
|
2013
|
tom 15
|
nr 2
122-127
EN
The production processes included catalytic dehydration of methanol in an adiabatic fixed-bed reactor and two columns product separations. In this study, the technological process for dimethyl ether (DME) synthesis is built on PRO/II platform based on the combined parameters of the reaction dynamic model for methanol dehydration reaction, the improved NRTL model of the liquid phase, the PR model of vapor phase. In order to validate the proposed model, the simulation results have been compared with the available data from a set of industrial production equipment with a production capacity of 200 000 tonnes per annum. A comparison between the calculated and measured results has proved that these results are satisfactory. The bed height and the volume of the catalytic bed are calculated aim at one million t/a DME yields and while taking account of high-purity DME production. After discussing the influence of feed stage location and reflux ratio for DME product purity, the suitable unit operation conditions are chosen. Accordingly, accurate process simulation results provide the basis and guidance for an improvement and development of the similar industrial device.
5
Content available An influence of correction of the ignition advance angle on the combustion process in SI engine fuelled by lpg with the addition of DME
100%
Kubica G. , Marzec P.
Journal of KONES
|
2019
|
tom Vol. 26, No. 4
285--292
EN
The paper presents the results of tests of the SI engine fuelled by LPG with the addition of DME in the form of a mixture of gaseous fuels. Experimental tests were carried out on a chassis dynamometer in the full range of engine loads, at a fixed rotational speed: 2000, 2500 and 3000 rpm. The use of dimethyl ether (DME) as a fuel component makes it possible to exploit its important advantages. DME can be produced as a renewable fuel, which is important from the point of view of ecology. Another important fact is the presence of oxygen in this fuel, which has a positive effect on the engine volumetric efficiency. During the tests, the ignition timing was also adjusted due to the very good DME flammability. Two additional correction levels were applied, increasing the ignition advance by 3 and 6 CA degrees, compared to the factory settings of the driver. The analysis of the obtained results allowed determining the dependence of the basic engine parameters, in the function of the correction of ignition advance angle. In the summary, attention was also paid to the possibility of determining corrected maps of the ignition advance angle taking into account the variable proportions of fuel components.
6
Content available remote COPPER/ZINC CATALYSTS IN HYDROGENATION OF CARBON OXIDES
88%
Kulawska M. , Madej-Lachowska M.
Chemical and Process Engineering
|
2013
|
tom 34
|
nr 4
479-496
EN
Polish Academy of Sciences, Institute of Chemical Engineering, 44-100 Gliwice, Bałtycka 5, Poland A review concerning main processes of hydrogenation of carbon oxides towards synthesis of methanol, mixture of methanol and higher aliphatic alcohols and one-step synthesis of dimethyl ether as well as methanol steam reforming is given. Low-temperature methanol catalysts and lowtemperature modified methanol catalysts containing copper as primary component and zinc as secondary one are described.
7
Content available remote Methanol dehydration to dimethyl ether using modified clinoptilolite
88%
Royaee S. J. , Sohrabi M. , Falamaki C.
Materials Science Poland
|
2007
|
tom Vol. 25, No. 4
1149--1160
EN
Clinoptilolite, a natural zeolite from the Semnan region in the West of Iran, has been converted to a catalyst for the methanol dehydration to dimethyl ether process. To produce such a catalyst and to create acidic sites on the latter, the ion-exchange process has been used. In addition, to investigate and optimize the effective factors of the catalyst synthesis process, a L9 Taguchi experimental design method has been implemented. The effects of four factors have been considered: the type of ion-exchange solution (2 levels); ion-exchange solution concentration; calcination temperature and calcination time (the last three factors have been studied in 3 levels). The yield of catalyst (conversion x selectivity) has been chosen as the response of the system. The catalytic behaviour of the produced samples was investigated using a fixed bed reactor (T = 350 oC, P = 1 atm and WHSV = 4.78 h-1 ). The results of the statistical design showed that the optimum conditions were: calcination time - 3 h, calcination temperature - 500 oC, ionexchange solution concentration - 2M, and ion-exchange solution - ammonium chloride. The optimum catalyst was tested using a fixed bed reactor at 330 oC, 1 atm and WHSV= 3.8 h-1 resulting in 98.1% conversion and 96.5% selectivity. In order to investigate the catalyst behaviour under industrial operating conditions, the catalyst was tested in a fixed bed reactor at 300 oC, 16 atm pressure, and WHSV = 52.5 h-1. The results were 67.02% conversion and 99.74% selectivity.
8
Content available remote Eter dimetylowy - surowiec do wytwarzania paliw silnikowych
75%
Molenda J.
Chemik
|
2004
|
tom Vol. 57, nr 9
332-336
PL
Przedstawiono własności, kierunki zastosowania oraz podano parametry i katalizatory stosowane w procesie otrzymywania eteru dimetylowego na drodze dehydratacji metanolu. Podano właściwości eteru dimetylowego jako paliwa do silników o zapłonie samoczynnym.
EN
Presented are properties, application trends, process conditions and catalysts used to give dimethyl ether (DME) by methanol dehydration. Also, properties of DME as a fuel for self-ignition engines are discussed.
9
Równowagowa konwersja ditlenku węgla w reakcji syntezy metanolu i w bezpośredniej syntezie eteru metylowego w warunkach nieidealnych
75%
Ptaszek A. , Grzesik M.
Inżynieria Chemiczna i Procesowa
|
2006
|
tom T. 27, z. 1
255-263
PL
Produkcja eteru metylowego może się odbywać bezpośrednio z H2, CO2 i CO lub pośrednio z metanolu w wyniku jego dehydratacji. Celem niniejszej pracy jest porównanie równowagowego stopnia przemiany ditlenku węgla w reakcji syntezy metanolu i w bezpośredniej syntezie eteru metylowego w warunkach nieidealnych.
EN
Dimethyl ether (DME) can be produced directly from z H2, CO2 i CO as well as from methanol in methanol dehydration process. The aim of this work was to compare the equilibrium conversion degree of CO2 in methanol synthesis to equilibrium conversion of CO2 in direct synthesis of DME under non-ideal conditions.
10
Content available remote Eter dimetylowy. Dokumentacja proponowanych wartości dopuszczalnych poziomów narażenia zawodowego
75%
Starek A.
Podstawy i Metody Oceny Środowiska Pracy
|
2003
|
tom Nr 2 (36)
177--187
PL
Eter dimetylowy jest bezbarwnym gazem stosowanym jako środek dyspergujący, chłodniczy, paliwo rakietowe oraz starter do silników benzynowych. W Polsce nie ma informacji o narażeniu na ten związek. Eter dimetylowy wywiera bardzo słabe, ostre działanie toksyczne, manifestujące się depresją ośrodkowego układu nerwowego (OUN). W warunkach narażenia powtarzanego, obok depresji OUN, pojawiają się zmiany hematologiczne we krwi obwodowej oraz hepatotoksyczne wyrażone wzrostem aktywności enzymów wskaźnikowych w surowicy. Nie wykazano działania genotoksycznego, rakotwórczego, embriotoksycznego, fetotoksycz- nego i teratogennego eteru dimetylowego. Za efekt krytyczny działania eteru dimetylowego przyjęto wzrost masy ciała i skrócenie czasu życia zwierząt w doświadczeniu przewlekłym. Wychodząc z wartości LOAEL eteru dimetylowego na poziomie 19100 mg/m3, wyznaczonej w doświadczeniu na szczurach na podstawie działania układowego i trzech współczynników niepewności o łącznej wartości 18, obliczono wartość NDS eteru dimetylowego i zaproponowano ustalenie jej na poziomie 1000 mg/m3. Nie ma podstaw do zaproponowania wartości NDSCh eteru dimetylowego, ponieważ substancja działa układowo i nie wykazuje działania drażniącego.
EN
Dimethyl ether (DME) is a colourless gas used mainly as a dispersant, refrigerant, racket fuel, and starter in a petrol engine. DME is relatively low toxic in laboratory animals during a single exposure. The central nervous system, hematopoietic system, and liver are major targets in DME subchronic and chronic toxicity. This compaund does not cause genotoxic, carcinogenic, embriotoxic, fetotoxic, and teratogenic effects. The proposed maximum exposure limit (MAC) of 1000 mg/m3 is based on the LOAEL value (19100 mg/m3) derived from long-term (104 weeks) studies on rats and relevant uncertainty factors.
11
Content available remote Badania kinetyki konwersji bioetanolu do eteru dimetylowego na katalizatorach zeolitowych zawierających miedź
75%
Nazimek D. , Zając G. , Słowik T. , Kuranc A. , Krzaczek P. , Szyszlak-Bargłowicz J. , Piekarski W. , Marczuk A.
Przemysł Chemiczny
|
2015
|
tom T. 94, nr 10
1778-1782
PL
Przedstawiono wyniki badań kinetyki procesu ETG ze szczególnym uwzględnieniem transformacji bioetanolu do DME na katalizatorach zeolitowych promowanych miedzią. Wyniki badań wskazują na szczególną rolę miedzi w podwyższeniu selektywności procesu w kierunku DME.
EN
Biomass-derived EtOH was converted to Me2O on optionally Cu-doped clinoptilolite, ZSM-35 zeolite and ferrierite at 660–730 K under 1.2 bar to det. the reaction kinetics and isokinetic temps. The selectivity of Me2O synthesis decreased with increasing SiO2/Al2O3 modulus of the catalyst.
12
Content available remote Kinetics of methanol dehydration to dimethyl ether over y-al2o3
75%
Ptaszek A. , Grzesik M.
Chemical and Process Engineering
|
2010
|
tom Vol. 31, z. 1
43-51
EN
The study presents the results of kinetic investigation of dehydration of methanol to methyl ether over y-Al2O3. Based on the experiments carried out in the range of 413.503 K, the kinetic equation of the reaction between an adsorbed methanol molecule and its molecule remaining in the gaseous phase has been determined.
PL
Przedstawiono wyniki badań kinetycznych reakcji odwodnienia metanolu do eteru metylowego na y-Al2O3. Na podstawie badań eksperymentalnych w zakresie 140.255 C pod ciśnieniem atmosferycznym opracowano postać równania kinetycznego reakcji powierzchniowej pomiędzy zaadsorbowaną cząsteczką metanolu i cząsteczką alkoholu pozostającą w fazie gazowej.
13
Content available The possibilities of using DME (BioDME), as an additive to conventional gaseous fuels in SI engine
75%
Flekiewicz M. , Kubica G. , Marzec P.
Combustion Engines
|
2017
|
tom R. 56, nr 4
150--155
EN
The results of SI engine fueled with blends of LPG and DME are presented in the paper. The range studies submitted includes measurements at varying engine loads, at selected values of speed. The research was conducted on a chassis dynamometer, specifying the engine load by the degree of throttle opening. Value of the mass fraction of DME in the blend with LPG was determined based on previous analyzes. The selected fuel blends containing from 7 to 17% DME (mass fraction). During the study was also performed a series of comparative measurements with pure LPG. Analyses show that of DME can be used as a partial substitute for LPG in SI engines. Its presence does not a negative impact on performance and emissions of the engine. The obtained results indicate that the amount of addition of DME should be varied depending on the engine load. Moreover, the use of this fuel does not require changes to the design fueling system and storage of LPG.
14
Content available COPPER/ZINC CATALYSTS IN HYDROGENATION OF CARBON OXIDES
75%
Kulawska M. , Madej-Lachowska M.
|
|
nr 4
15
Content available Assessment of the potential of dimethyl ether as an alternative fuel for compression ignition engines
63%
Smolec R. , Idzior M. , Karpiuk W. , Kozak M.
Combustion Engines
|
2017
|
tom R. 56, nr 2
181--186
EN
The main problem that the automotive industry has been dealing with since the beginning of the XXI century is the need to reduce the exhaust emissions from piston combustion engines. Another, not at all less important problem is the depleting natural resources of crude oil. There are many concepts aiming at resolving of the said issues. One of them is the possibility of application of dimethyl ether (DME) in a classic engine. The paper characterizes this fuel, drawing attention to the aspects related to the adaptation of the engine to this type of fuel, presents the process of its atomization and relevant exhaust emissions.
16
Content available remote Eter dimetylowy : właściwości, technologie produkcji i rynek
63%
Krupa M. , Moskalewicz M. , Sikora A. P. , Szurlej A.
Przemysł Chemiczny
|
2014
|
tom T. 93, nr 9
1621-1627
PL
W Unii Europejskiej pojawia się miejsce na ciekawe, a dla wielu nowe źródło energii, szczególnie warte rozważenia w okresie budowania nowego wspólnego rynku gazu ziemnego. Przedstawiono właściwości, sposoby otrzymywania i główne uwarunkowania zapotrzebowania na DME, który jest produkowany bądź z metanolu, bądź z gazu ziemnego. Produkcja DME może być szansą do wykorzystania przez krajowych producentów.
EN
A review, with 26 refs., of properties, methods for prodn. and uses (esp. as fuel) of Me2O. Some economic information were also included.
17
Content available Copper/zinc catalysts in hydrogenation of carbon oxides
63%
Kulawska M. , Madej-Lachowska M.
Chemical and Process Engineering
|
2013
|
tom Vol. 34, nr 4
479--496
EN
A review concerning main processes of hydrogenation of carbon oxides towards synthesis of methanol, mixture of methanol and higher aliphatic alcohols and one-step synthesis of dimethyl ether as well as methanol steam reforming is given. Low-temperature methanol catalysts and low-temperature modified methanol catalysts containing copper as primary component and zinc as secondary one are described.
18
Content available Modelling of methane dry reforming over Ni/CaO–Al2O3 catalyst
63%
Cherbański R. , Lewak M. , Machniewski P. , Molga E. , Franczyk E.
Chemical and Process Engineering
|
2021
|
tom Vol. 42, nr 3
235-–252
EN
This paper presents the results of investigations into dry methane reforming (DMR). The process was aimed at obtaining synthesis gas required for the production of dimethyl ether (DME). The effect of temperature, pressure and inlet gas composition on the process was determined in the experimental part of this work. The tests were carried out in a laboratory tubular reactor over a Ni/CaO–Al2O3 catalyst. The obtained experimental results were used to verify literature kinetic data and to develop a mathematical model of the DMR process.
19
Content available DME as alternative fuel for compression ignition engines - a review
63%
Stepanenko D. , Kneba Z.
Combustion Engines
|
2019
|
tom R. 58, nr 2
172--179
EN
The ecological issues and the depletion of crude oil, has led the researchers to seeking for non-petroleum based alternative fuels, along with more advanced combustion technologies, and after-treatment systems. The use of clean alternative fuels is the one of the most perspective method that aiming at resolving of the said issues. One of the promising alternative fuels that can be used as a clean high-efficiency compression ignition fuel with reduced of toxic emissions is dimethyl ether (DME). Moreover, it can be produced from various feedstocks such as natural gas, coal, biomass and others. This article describes the properties and the potential of DME application on the combustion and emission reduction characteristics of the compression ignition engines.
20
Content available remote Kinetyka dehydratacji metanolu do eteru dimetylowego na katalizatorze zeolitowym H-ZSM-5
51%
Grzesik M. , Ptaszek A. , Skrzypek J. , Derewiński M.
Przemysł Chemiczny
|
2012
|
tom T. 91, nr 7
1388-1392
PL
Przedstawiono wyniki kinetycznych badań reakcji odwodnienia metanolu do eteru metylowego na H-ZSM-5 w zakresie temp. 403–483 K. Dla badanej reakcji wyznaczono parametry równania kinetycznego Langmuira i Hinshelwooda. Wpływ wody na aktywność katalizatora i wydajność eteru był niewielki.
EN
H form of H-ZSM-5 zeolite was prepd. and used for MeOH dehydration to Me₂O at 403–483 K. Parameters of the Langmuir-Hinshelwood kinetic equation of the reaction were detd. The effect of water on the catalyst activity and Me₂O yield was negligible.
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