Uses • •
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Dimethyl ether is used as an aerosol spray propellant, and is used in conjunction with propane to give a thermic expansion that lowers temperature to -60°C. Dimethyl ether (DME) is a useful chemical intermediate for the preparation of many important chemicals, such as dimethyl sulfate and high-value oxygenated compounds. DME is used as: A refrigerant , A (co-)blowing agent for foam , A propellant for aerosol products , A solvent , An extraction agent , A chemical reaction medium , A fuel for welding cutting and brazing , A multi-purpose fuel. DME could be used as a new clean fuel for various fields; residential, transportation, power generation, etc as LPG.
Market • • • •
The largest market for DME is Asia where the capacity has steadily increased and will continue to grow with new plants constructed for the domestic fuel market. DME production capacity in China needs to exceed 11 million mt for use as a domestic fuel by 2012 to be cost effective in the domestic fuels market. The total production of DME today is between 100,000 and 150,000 metric tons per year The future development of the market for DME as a fuel for power production or automotive transportation will require much larger quantities of DME at a much lower cost.
Introduction of dimethyl ether: Dimethyl ether (DME) is the organic compound with the formula CH3OCH3. The simplest ether, it is a colourless gas that is a useful precursor to other organic compounds and an aerosol propellant. When combusted, DME produces minimal NOx and CO, though HC and soot formation is significant. DME can act as a clean fuel when burned in engines properly optimized for DME.
Applications The largest use of DME is currently (2010) as substitute for propane in LPG used as fuel in household and industry.[6] The largest use of DME for this purpose is in China. DME has two other primary applications: as a propellant in aerosol canisters, and as a precursor to dimethyl sulfate.[3][7] As an aerosol propellant, DME is useful as a somewhat polar solvent. It can also be used as a refrigerant.
Feedstock Several thousand tons of DME are consumed annually for the production of the methylating agent, dimethyl sulfate, which entails its reaction with sulfur trioxide: CH3OCH3 + SO3 → (CH3O)2SO2 DME can also be converted into acetic acid using carbonylation technology related to the Monsanto acetic acid process:[3]
(CH3)2O + 2 CO + H2O → 2 CH3CO2H
Laboratory reagent and solvent DME is a low-temperature solvent and extraction agent, applicable to specialised laboratory procedures. Its usefulness is limited by its low boiling point (−23 °C), but the same property facilitates its removal from reaction mixtures. DME is the precursor to the useful alkylating agent, trimethyloxonium tetrafluoroborate.[8]
Fuel
Installation of BioDME synthesis towers at Chemrec's pilot facility DME is a promising fuel in diesel engines,[9] petrol engines (30% DME / 70% LPG), and gas turbines owing to its high cetane number, which is 55, compared to diesel's, which is 40–53.[10] Only moderate modification are needed to convert a diesel engine to burn DME. The simplicity of this short carbon chain compound leads during combustion to very low emissions of particulate matter, NOx, CO. For these reasons as well as being sulfur-free, DME meets even the most stringent emission regulations in Europe (EURO5), U.S. (U.S. 2010), and Japan (2009 Japan).[11] Mobil is using DME in their methanol to gasoline process. DME is being developed as a synthetic second generation biofuel (BioDME), which can be manufactured from lignocellulosic biomass.[12] Currently the EU is considering BioDME in its potential biofuel mix in 2030;[13] the Volvo Group is the coordinator for the European Community Seventh Framework Programme project BioDME[14] [15] where Chemrec's BioDME pilot plant based on black liquor gasification is nearing completion in Piteå, Sweden.[16] The image below illustrates some of processes from various raw materials to DME.
Refrigerant DME is also gaining popularity as a refrigerant[18] with ASHRAE refrigerant designation R-E170. DME is also used in refrigerant blends with e.g. butane and propene.[19]
Treating warts A mixture of DME and propane is used in an over-the-counter device to treat warts, by freezing them.[20][21]
Safety Unlike other alkyl ethers, DME resists autoxidation. DME is also relatively non-toxic, although it is highly flammable.
DME: Multi-Use, Multi-Source Low Carbon Fuel
Transportation
Cooking & Heating
Power Generation
Significant commercial and regulatory developments worldwide are driving increases in DME production capacity, and demonstrating its remarkable potential as an ultra clean, renewable, low-carbon fuel. The IDA serves as the global voice for the DME industry, and works to promote the use of DME as a clean alternative fuel worldwide, to gather and communicate authoritative information about DME, and to coordinate relevant international activities and initiatives. The IDA has a global membership of companies, institutions, and individuals from Asia, Africa, the Americas, Australia, Europe and the Middle East, and from every sector of the industry, representing a wide range of interests within both the upstream and downstream value chains.
About DME What is DME? DME (dimethyl ether) is a clean, colorless gas that is easy to liquefy and transport. It has remarkable potential for increased use as an automotive fuel, for electric power generation, and in domestic applications such as heating and cooking. DME can be derived from many sources, including renewable materials (biomass, waste and agricultural products) and fossil fuels (natural gas and coal). DME has been used for decades in the personal care industry (as a benign aerosol propellant), and is now increasingly being exploited for use as a clean burning alternative to LPG (liquefied petroleum gas), diesel and gasoline. Like LPG, DME is gaseous at normal temperature and pressure, but changes to a liquid when subjected to modest pressure or cooling. This easy liquefaction makes DME easy to transport and store. This and other properties, including a high oxygen content, lack of sulfur or other noxious compounds, and ultra clean combustion make DME a versatile and promising solution in the mixture of clean renewable and low-carbon fuels under consideration worldwide. How is DME Produced? DME can be produced from a variety of abundant sources, including natural gas, coal, waste from pulp and paper mills, forest products, agricultural by-products, municipal waste and dedicated fuel crops such as switchgrass. World production today is primarily by means of methanol dehydration, but DME can also be manufactured directly from synthesis gas produced by the gasification of coal or biomass, or through natural gas reforming. Among the various processes for chemical conversion of natural gas, direct synthesis of DME is the most efficient.
For more than a decade, some researchers have been advocating use of dimethyl ether (CH3OCH3) as a transportation fuel. Why? Because it is much less toxic than the methanol from which it is usually made, and fossil-derived methanol (from either coal or natural gas) has been rather cheap over most of the past decade. DME (also sometimes called PROZONE, Ice Blue, or Blue Fuel) has the same empirical formula as ethanol (C2H6O), but its structure is different, as shown by their structure-based formulae, CH3OCH3 and C2H5OH respectively. Chemically and physically, they are very different. Ethanol is a safe, familiar, stable liquid, while the normal boiling point of DME is -23oC – not much different from that of propane (-42oC). Hence, DME must be stored in compressed tanks, which complicates filling. Moreover, the energy density of DME is only 61% that of propane, so much larger tanks are required for DME and the vehicle range is about half that for gasoline. At first glance, the hazards of ethanol and DME may appear similar. The primary effects of DME are anesthesia, headache, intoxication, and unconsciousness. However, the vapor pressure of ethanol at room temperature is under 0.09 bar, so spills don’t
result in high enough concentrations to be intoxicating. DME leaks, on the other hand, can easily produce intoxicating concentrations even outside, as the heavy gas doesn’t rise. The fire hazards are also much worse for DME. DME leaks readily form explosive mixtures, even on the coldest winter days. Its flash point is -41oC. On the other hand, the autoignition temperature of ethanol is quite high (over 360oC) and its flash point is 13oC, so ethanol spills are not very hazardous – less so than diesel spills (the autoignition temperature of diesel is 210oC, though its flash point is 135oC). (The autoignition temperature is the temperature at which a fire will start without a spark, and the flash point is the lowest temperature at which a fire can be started with a spark in normal air.) The best routes for making DME are from methanol, so it’s important to look at it first. Methanol has been made from natural gas in very large plants (over 100,000 bbl/day) at efficiencies up to 65%. Undoubtedly, there is room for improvement (perhaps up to 73% efficiency) as energy costs increase, and there are theoretical reasons to expect that the efficiency of making methanol from renewable H2 and CO2 should be a little higher – perhaps up to 80% in large, highly optimized plants. Some http://energysynergy.ca/ have claimed they will achieve 95% efficiency efficiency making methanol from H2 and CO2 in plants under 1% as large as current industrial scale methane-to-methanol plants – using processes that have not yet been publicly disclosed. Perhaps 65% is more realistic. DME will always be much more expensive than methanol per unit energy. Some advocates believe the minimum energy losses in conversion of methanol to DME can be as low as 5%, but 15% is probably typical. Because of DME’s low energy density, distribution costs will be at least 30% higher than for propane, for which distribution costs to consumers (refilling barbeque grill-sized tanks, 4.73 gal) are typically 20 times those for gasoline. Hence, a reasonable estimate (from the combination of conversion and distribution costs) is that DME would likely cost consumers three times as much per unit energy as methanol, at least until DME-vehicles are in wide usage, which would take more than three decades even with favorable economics. What about end use in small engines? Small diesel engines have demonstrated efficiency over 45%, gasoline engines can achieve 35%, and high-compression advanced E85 engines should ultimately be able to exceed 45% efficiency. The best thus far from DME engines is about 30% and it’s not clear how much room for improvement there is. DME from fossil-derived methanol doesn’t reduce CO2 emissions. It increases them compared to convention diesel – mostly because of the huge CO2 releases from the plants producing the methanol and because of the reduced efficiency of DME engines. It is true that methanol from renewable H2 (as from water electrolysis using wind energy) would allow the production of carbon-neutral methanol and hence carbon-neutral DME. However, substantial investment in production of carbon-neutral methanol (~$1/kg) seems unlikely as long as fossil-derived methanol is half as expensive. The price disadvantage for "green" DME will be enormous. Carbon-neutral ethanol, gasoline, jet fuel, diesel and other standard fuels from Doty WindFuels processes will be much cheaper per unit energy (for the consumer) than carbon-neutral DME. More important, however, is the fact that fossil derived petroleum products will be significantly more expensive than Windfuels products, and the end-use of WindFuels within the current infrastructure will be seamless and efficient.
Safety data for dimethyl ether
Glossary of terms on this data sheet. The information on this web page is provided to help you to work safely, but it is intended to be an overview of hazards, not a replacement for a full Material Safety Data Sheet (MSDS). MSDS forms can be downloaded from the web sites of many chemical suppliers.
General Synonyms: oxybismethane, wood ether, dimethyl oxide, methyl ether Use: solvent, aerosol propellant, refrigerant, fuel Molecular formula: C2H6O CAS No: 115-10-6 EC No: 204-065-8
Physical data Appearance: colourless gas Melting point: -138 C Boiling point: -22 C Vapour density: 1.62 (air = 1) Vapour pressure: Specific gravity: Flash point: -41 C Explosion limits: 3.4 % - 18 % Autoignition temperature: 350 C Critical temperature 127C Critical pressure 53.5 atm Solubility in water: slight
Stability Stable. Extremely flammable. Note low flash point. May form explosive mixtures with air. May form peroxides during prolonged storage.
Toxicology Narcotic in high concentration. Little toxicological effect in normal industrial or research use. May cause dematatitis with repeated exposure. Exposure to the low-temperature liquid may cause frostbite. Typical OES TWA 500 ppm. Toxicity data (The meaning of any abbreviations which appear in this section is given here.) IHL-MUS LC50 386 ppm (15 min.) IHL-RAT LC50 300 g/m3. Risk phrases (The meaning of any risk phrases which appear in this section is given here.) R12.
Personal protection Safety glasses. Good ventilation. Remove all sources of ignition from working area.
Safety phrases (The meaning of any safety phrases which appear in this section is given here.) S9 S16 S33
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It can be produced from methanol through a process of catalytic dehydration.[3] It can be produced via syngas produced through gasification of biomass or coal.[3]
Diagram showing the production process for DME
MSDS of dimethyl ether: Product: Dimethyl Ether P-4589-D Date: May 2009 Page 2 of 9 Effects of Repeated (Chronic) Overexposure. Repeated overexposure of the skin to liquid dimethyl ether can cause cracking and drying. Repeated inhalation may cause loss of appetite, exhaustion, headaches, sleepiness, dizziness, excitation, and psychic disturbances. Other Effects of Overexposure. None known. Medical Conditions Aggravated by Overexposure. The defatting properties of dimethyl ether on the skin can aggravate an existing dermatitis. CARCINOGENICITY: Dimethyl ether is not listed by NTP, OSHA, or IARC. POTENTIAL ENVIRONMENTAL EFFECTS: None known. For further information, see section 12, Ecological Information.
3. Composition/Information on Ingredients See section 16 for important information about mixtures. COMPONENT CAS NUMBER CONCENTRATION Dimethyl ether 115-10-6 >99%* *The symbol > means “greater than.”
4. First Aid Measures INHALATION: Remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, qualified personnel may give oxygen. Call a physician. SKIN CONTACT: For exposure to liquid, immediately warm frostbite area with warm water not to exceed 105°F (41°C). In case of massive exposure, remove clothing while showering with warm water. Call a physician. SWALLOWING: An unlikely route of exposure. This product is a gas at normal temperature and pressure. EYE CONTACT: Immediately flush eyes thoroughly with warm water for at least 15 minutes. Hold the eyelids open and away from the eyeballs to ensure that all surfaces are flushed
thoroughly. See a physician, preferably an ophthalmologist, immediately. NOTES TO PHYSICIAN: There is no specific antidote. Treatment of overexposure should be directed at the control of symptoms and the clinical condition of the patient.
5. Fire Fighting Measures FLAMMABLE PROPERTIES: Flammable gas. SUITABLE EXTINGUISHING MEDIA: CO2, dry chemical, water spray, or fog PRODUCTS OF COMBUSTION: CO, CO2 PROTECTION OF FIREFIGHTERS: DANGER! Flammable liquid and gas under pressure. Evacuate all personnel from danger area. Immediately spray cylinders with water from maximum distance until cool, taking care not to extinguish flames. Remove sources of ignition if without risk. Remove all cylinders from fire area if without risk; continue cooling water spray while moving cylinders. Do not extinguish any flames emitted from cylinders; stop flow of gas if without risk, or allow flames to burn out. Self-contained breathing apparatus may be required by rescue workers. On-site fire brigades must comply with OSHA 29 CFR 1910.156.
1. Background and process overview_ Dimethyl ether (DME) is a clean energy source and as it generates no sulfur oxide or soot during combustion its environmental impact is low. Owing to its non-toxicity and easy liquefaction properties, DME is easy to handle and therefore can be used as a domestic-sector fuel (substitute for LPG), transportation fuel (diesel vehicles, fuel cell vehicles), power plant fuel (thermal plants, cogeneration plants, stationary fuel cells), and as a raw material for chemical products. Currently DME is produced by dehydrating methanol. Approximately ten thousand tons per year are produced in Japan, and 150 thousand tons per year worldwide. DME’s main use is as a spray propellant. Given the above-described superior properties, if DME were to become widely available in large volumes at a reasonable price, DME could be used as a fuel in a wide variety of fields.
