1
$\begingroup$

How to modify a transport device with an internal combustion engine with:

  1. the methane-nitrogen atmosphere
  2. carbon dioxide atmosphere
  3. the atmosphere of argon and chlorine.

Which substances will react? How will they feed? How effective will it be?

$\endgroup$
2
  • 2
    $\begingroup$ Welcome to Chemistry.SE! Feel free to take a tour of the site, and see How to Ask for details about asking a great question. Please note that we have a policy which states that you should show your thoughts and/or efforts into solving homework problems. It'll make us certain that we aren't doing your homework for you. Otherwise, this question may get closed. Please edit in your reasoning or thoughts on this. $\endgroup$ – user7951 Dec 22 '16 at 13:57
  • 1
    $\begingroup$ Related: Is oxygen necessary for burning? and Can oxygen burn in hydrogen?. $\endgroup$ – user7951 Dec 22 '16 at 13:59
0
$\begingroup$

Each of the cases will strongly depend on the non-atmospheric natural resources available on each planet.

For example in an atmosphere of $\ce{O2}$ + inert gases, it would be desirable to have deposits of hydrocarbons or $\ce{H2}$ gas to be mined and pumped into your fuel tank to burn with the atmospheric $\ce{O2}$. In each case proposed below it is assumed that the non-atmospheric reagents would be available as deposits on the planet or that they could be synthesized in a way that they are acting as batteries, storing the energy that went into their synthesis. That said, here are some possible simplistic solutions for the different scenarios.

Scenario 1: $\ce{CH4}$ + $\ce{N2}$ atmosphere:

Here you could simply reverse the typical internal combustion engine process used in Earth-vehicles. Rather than filling your tank with hydrocarbons to be mixed and burned with atmospheric $\ce{O2}$, you would fill your tank with (probably liquid to keep the volume small) $\ce{O2}$ to be mixed and burned with atmospheric $\ce{CH4}$. Just as with conventional internal combustion engines on Earth, the reaction products would be $\ce{H2O}$, $\ce{CO2}$, and heat.

Scenario 2: $\ce{CO2}$ atmosphere:

As $\ce{CO2}$ is already thoroughly oxidized, you would need to fill your tank with a good reducing agent. If there were deposits of $\ce{H2}$ gas trapped within the planet, then you would mine the $\ce{H2}$ and fill your tank with pressurized $\ce{H2}$ gas (the resources required to form and store liquid $\ce{H2}$ just wouldn't be worth the trouble, though there are other ways to concentrate $\ce{H2}$ then liberate it when needed). The $\ce{H2}$ would then be mixed and burned with $\ce{CO2}$, ideally giving off $\ce{CH4}$, $\ce{H2O}$ and heat as products.

Scenario 3: $\ce{Ar}$ + $\ce{Cl2}$ atmosphere:

First to address is the composition of the vehicle, or at least the parts that would come into contact with the $\ce{Cl2}$ and other reactants and products, I propose a $\ce{SiO2}$ based coating for all components that would be in such contact. For a gas-phase ignition scenario, I propose a diesel type of concept (ignition heat from compression of the mixed gases) to avoid the need for electrical ignition, metal wires, etc.

One possibility is to use the $\ce{Cl2}$ analogously to how $\ce{O2}$ is used in internal combustion engines, namely as the oxidant. A hydrocarbon, $\ce{CH4}$ to keep it simple, would act as the reductant. This reaction would ideally produce $\ce{CCl4}$, $\ce{HCl}$ and heat. The atmosphere is already toxic and corrosive so the $\ce{HCl}$ exhaust is probably OK.

In the same manner as the $\ce{CO2}$ atmosphere, $\ce{H2}$ is another possibility. In this case, the ideal reaction product is just $\ce{HCl}$.

One final possibility is worth considering here. In all other scenarios I've only proposed fluids as fuel for the combustion. But $\ce{Cl2}$ reacts very exothermically with $\ce{Fe}$ metal. And the ideal product, $\ce{FeCl3}$, is also a solid. So introducing a fine iron dust in some carrier gas could actually have the advantage of ease of collecting the exhaust do be disposed of at a dedicated treatment center. That way we wouldn't pollute the air for the $\ce{Cl2}$-breathing natives.

Note that most of the proposed fuels here are composed of some of the most abundant elements in the universe.

$\endgroup$

Not the answer you're looking for? Browse other questions tagged or ask your own question.