Questions tagged [fuel]
Questions regarding fuels and the properties of fuels, like calorific value, octane number, mechanism of combustion, etc., should use this tag.
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Can we revers the process of plastics to fuel
I am a 10th grade student who is trying to convert plastics into fuel.
My question is that when we can make plastic from oil/fuel then can we revers the process?
But we should be able to revers the ...
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Please explain the difference between HFC technology and PEMFC technology
I understand how hydrogen fuel cells (HFCs) function, but what are the differences between them and PEMFC's?
I know that there are HT-PEMFCs and LT-PEMFCs, for low and high temperatures.
Do PEMFCs ...
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Testing Combustion Kinetic Mechanisms
The chemical modeling of combustion depends on kinetic mechanisms, that is, intricate networks of chemical reactions that describe the transformation of reactants into products. For a mechanism of $...
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Can cyclopentylmethyl ether replace the use of methyl tert-butyl ether as an octane improvement additive
Can the replacement of methyl tert-butyl ether as an octane enhancer with cyclopentyl methyl ether be a better choice as a more eco friendly solution?
https://www.sigmaaldrich.com/CA/en/product/sial/...
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How is the amount of electrolyte per kilowatt in a Molten Carbonate Fuel Cell calculated?
While searching for Molten Carboante Fuel Cells I notice that quite a lot of them are really big, for example, this 250 kilowatt MCFC is the size of a truck.
Asking "why it is that big" can'...
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Is there not a strict definition of what naphtha vs petrol represent?
If you search for information about fractional distillation of petroleum, many sources place petrol above naphtha, while others do the reverse.
Is there not a strict definition of what these compounds ...
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Does polyamide react with hydrocarbons (group III engine oil) in its thermoplastic state?
I need to form (bend) thermoplastic polyamide hose in rubber jacket to a desired shape.
I can use heat gun but I thought for better results I could use heated to 150C group III engine oil (your ...
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How do I calculate the fuel consumption inside a cylinder-piston stoichiometrically?
Consider I have car 4-cylinders with total cylinder capacity is 1,496cc. Per piston, the cylinder is 374cc. The piston diameter is 72.5mm, height=90.6mm, and compression ratio is 11.5:1. Hence we may ...
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What additives can make an ethanol flame incandescent? (Historical setting)
How can I make the flame in a wicked lamp incandescent when using azeotropic ethanol (95% ethanol with 5% water) as the primary fuel in a 'hurricane lamp'? (Ethanol burns with an almost invisible ...
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Why is coal and charcoal a good fuel, but not graphite?
Correct me if I'm wrong, but coal(after coking) and charcoal are essentially hard dry lumps of pure carbon.
But of course so is graphite. I understand of course the structure is different lending them ...
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Is it possible to make a reversible "Solid State" Hydrogen fuel cell using Ammonia Borane and Iron Oxide? [closed]
Well, I saw this video about hydrogen reduction, in which pure hydrogen gas is exposed to iron oxide at high temperatures, producing water vapor and leaving pure iron behind.
And as such, I wondered ...
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How well the conclusion from the "Ignition!" book on rocket fuel science stood the test of time?
There was a wonderful book called "Ignition!" by John D. Clark, published around 1972, very interesting to read. That book covers the history of the rocket fuel development in the middle of ...
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How does tetraethyl lead prevent knocking?
My understanding of knocking is that in a spark ignition engine as the fuel is being compressed it heats up. The heat causes some of the oxygen to break up into oxygen radicals the $\ce{O^.}$ ...
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Flash point of naptha and propanol
I filled a Zippo lighter with 2-propanol and it lit up easily when the ambient temperature was around 6-7 degrees Celsius.
It was impossible to light it up when the temperature was around 3-4 degrees ...
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Effect of coal and natural gas burning on particulate matter pollution
I sometimes hear people talking about how we should replace coal burning plants with natural gas ones, to alleviate the case of particulate matter pollution. What exactly is the difference between ...
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Are solid fuels with calorific values >= 10,000 kcal/kg (42 MJ/kg) physically possible?
I have seen laboratory documentation from a reputable lab in southeast Asia that a company has achieved a solid fuel product made from landfill material with a high heating calorific value ($CV$) of ...
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What chemicals can remove or greatly reduce the smell of burning diesel fuel?
I am not a chemist myself but I am trying to solve a practical problem I am experiencing.
I have a nicely working diesel stove but it produces some smell.
I've read that adding urea to the exhaust may ...
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Where does the energy in coal bonds come from?
I have been told that when the plants intake carbon dioxide they break carbon and oxygen apart and the carbon is utilised in making the plant's body. This process is driven by the sun's energy so when ...
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how to make a PEM (proton exchange membrane) out of Nafion Dispersions?
I would like to use a Nafion membrane for a fuel cell project, but the Nafion sheets are hard to integrate. Therefore, I would like a gel type of Nafion that can take the shape of the container I put ...
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Hydrogen fuel cell purity / concentration
This is a chemistry/technology kind of question. Some PEM fuel cells work with a rated hydrogen purity of 99.99%.
What would happen if the fuel cell stack is supplied with a hydrogen purity/...
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Would a PNG geyser work on biogas?
I am trying to understand if a water heater designed to run on piped natural gas (PNG) could be powered by biogas without any modifications. Typically, these geysers have a battery-powered ignition ...
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Why do some biofuels have a maximal blending ratio?
ICAO has several conversion processes for sustainable aviation fuel (SAF) with various maximal blending ratios. What would happen if we tried to increase the blending ratio with these processes?
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Is a hydrocarbon necessary for combustion? [closed]
Oxygen, heat and fuel are essential for combustion. What counts as a fuel? Is a hydrocarbon essential for combustion? Is combustion, say, of magnesium really combustion? And what's the difference ...
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Which is more efficient way to generate energy using hydrogen: direct hydrogen combustion or through fuel cell? [closed]
Which is more efficient way to generate energy using hydrogen: direct hydrogen combustion or through fuel cell? Please explain so that even a primary school student can understand.
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Is a hydrocarbon bio-battery feasible?
Hydrocarbons have some of the highest energy densities and specific energies of any chemical fuel. Unfortunately, our primary use of them is in thermal engines, whose efficiency is limited by Carnot'...
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Can oxidizing agents be used to increase the combustion efficiency of waste oil?
Waste oil is atomized and combined with air to produce a very high temperature flame capable of melting iron. I was wondering if it's possible to further increase its combustion efficiency by mixing ...
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Does all fire only emit light on its outermost shell?
This question is about light emission, which may overlap with physics, but I am most interested in combustion and types of flame (incandescence, petrochemical fuel flames, nuclear reactions).
Consider ...
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What is the explanation of negative temperature coefficient in ignition delay of a fuel?
When studying the ignition delay of a fuel, some fuel have a negative temperature coefficient area (NTC) where an increase of initial temperature of the mixture air/fuel produces an increase of the ...
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Could you use All-Purpose Flour as a model rocket fuel?
I'm building a model rocket, and I'm trying to find a good fuel. I've done a lot of research and I know about r-candy and the aluminum-ammonium fuel, but I was wondering, before I made any of these, ...
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Can you make R-Candy without heating the propellant mix?
I'm wondering if there's any way you can make "Rocket Candy" (or R-candy) fuel without cooking it. I'm building a model rocket that I'm hoping will get about 3 km on my first build (It's not ...
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Small scale gas-to-liquids via Fischer–Tropsch — is it even possible?
I'm really interested in the Fischer–Tropsch gas-to-liquids (GTL) process. A lot of people are using wood or other biomass feedstock to make syngas on small scales (farms, shops, etc.).
Practically, ...
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What is the carbon content, by weight, of vegetable oil?
I have only a high school understanding of chemistry, so please bear with me and my ham-fisted question. I’m trying to understand the carbon content in vegetable oil. I get that various oils have ...
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Is incineration of a solid fuel complete or incomplete?
If I have some solid material like biomass and incinerate it at 1000 Celsius degrees for 15 minutes in an oxidized atmosphere within an incineration oven. As an output it gives me ash. Is the ...
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Why doesn't NASA or SpaceX use ozone as an oxidizer for rocket fuels?
Presumably, it would be expensive to use ozone ($\ce{O3}$) as an oxidizer instead of $\ce{O2}$, but would the extra oomph be worth it? Does $\ce{O2}$ provide as much thrust/energy/heat as can be ...
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Combustion of methane and ethane
I'm having trouble with the following problem:
A gas fuel of Methane ($\ce{CH4}$) and Ethane ($\ce{C2H6}$) is burned
with atmospheric air, and the volumetric analysis of the products of
combustion ...
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Realistic conditions for fuel container explosion [closed]
First off, I'm not actually trying to blow anything up. Also, my apologies if this isn't the right SE to ask. If so, I'd appreciate it if you could point me to the right SE.
I'm writing something ...
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How do i get acetic acid from vinegar?
I'm trying to improve my rocket project, but, since the competition only allows the use of vinegar and sodium bicarbonate as its fuel, I had an idea of using the vinegar in a different way. My plan ...
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Why are branched alkanes used as fuels instead of straight chain alkanes?
My textbook states that branched alkanes are thermodynamically more stable than straight chain alkanes. Of course, iso-octane has an enthalpy of formation of $\Delta H_\mathrm f$= $\pu{-259.34 kJ mol-...
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fuel with the narrowest boiling temperature? [closed]
What commercially available fuel, such as kerosene or diesel, has the least variation in different hydrocarbon chains and thus the most uniform boiling point? I ask this because I'm searching for a ...
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How or Why does diesel/kerosene have a much higher 'flash point' but lower auto/self-ignition point than gasoline/petrol?
This is a very common question, but I have yet to find a good theoretical answer to both questions (diesel has higher flash point BUT lower spontaneous ignition temp.)
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Comparison of energy release from different types of fuels [closed]
I've recently been reading about the different amount of energy release for different types of fuels/hydrocarbons.
Anyways, I was wondering why butanol would release more energy (kj/mol) than methanol?...
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What does the alcohol functional group (specifically oxygen) have to do that causes an alcohol to have a lower energy content than an alkane? [closed]
My textbook said that the carbon is "partially oxidised" (don't really know what that means) and I just wanted to confirm.
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How to get the right formulas for combustion (rocket chamber) or where to find them? [closed]
I am a space enthusiast and am intrigued mostly by rockets.
I recently found a book HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUEL ROCKET ENGINES and have been fiddling around with rocket engine ...
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How is octane rating defined for negative values and those over 100?
Based on my reading, the octane rating for a given fuel is calculated by finding the compression ratio at which it knocks and finding a mixture of $X\%$ isooctane and $(100 - X)\%$ n-heptane which ...
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What chemical reactions could ancient people use to propel projectiles? [closed]
Are there reactions other than burning of gunpowder that ancient people could perform that would produce gas from non gaseous substances, so that it could have been used for propulsion of projectiles ...
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Why does Sodium Bicarb. Reduce Combustion Rate? [closed]
In many common solid-propellant model rocket engines, Sodium Bicarbonate, $\ce{NaHCO3}$, is used to predictably regulate/limit the rate of combustion of the fuel. My questions are as follows:
What is ...
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Rocket Candy Fuel - Common Alternatives to KNO3?
I'm sort of a model rocket enthusiast, but the most common fuel for model rockets, Rocket Candy, requires Potassium Nitrate as an oxidizer to oxidize Powdered Sugar. Potassium Nitrate is not ...
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Is it possible to have a negative overall activation energy for a whole reaction mechanism?
I am trying to find out correlation for ignition delay for alkane fuels. The activation energy part of the correlation gives me a negative value.
For the ignition delay formulation, is it possible to ...
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Equation of combustion of heavy fuel oil (HFO)
We are researching the use of heavy fuel oil (HFO) on ship vessels, but are having trouble finding the equation of the chemical combustion process of HFO. I understand that it contains long chains of ...
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Are there any chemical pathways or catalysts that could produce electricity from fossil fuels without combustion?
While fossil fuels are dense in energy, I have known only one way to retrieve energy from them, namely, to burn them. I wish we could have a way to get energy from them without combustion.
Is there ...
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