Is this too difficult?
Or is it too easy for you?
Wrong sub-forum, maybe... But I have no intention to become a chemist, so an answer obvious for everyone else would be fine to me!
The challenge is the landscape. It is virtually being assumed that the Russians, Europeans, and NASA don't know what they are doing. Don't they know that bicyclobutane is a superior and cheap rocket fuel that can be readily prepared in multi-ton quantities?
From my experience, you are far more likely to be successful by utilizing something that has already been shown to work over something that even experts might predict should
work but has never been demonstrated to
work. Bicyclobutane is apparently a known compound based upon the patent previously cited. That seems a far better starting process than any thought of joining two cyclobutanes. My instinct is that any chemists here would suggest you can forget bicyclobutane as an alternate to kerosene on a cost basis if it is gives only a 2% improvement. However, I could be wrong. How was it prepared?
No matter, let's try it based upon hypothetical economics. Let us assume that cyclobutane can be dimerized into bicyclobutane in a single step and in 100% yield. Let us further assume cyclobutane is commercially available in ton quantities at the same price as kerosene. All that is needed is to turn the crank and we're off.
The cost to turn the crank on this process is $25/kg. That seems reasonable based upon my experience. If some of the other chemists with industrial experience can suggest another value, that is fine also. We had used a slightly higher value 15 years ago. This is where I got the $25/kg value from. http://greenchem.uoregon.edu/ACSGoingGreenSite/PDFs/20050315TuesPM/1336Cue.pdf
My experience tells me you cannot couple cyclobutane, cyclobutane is going to be far more expensive than kerosene, the known route to bicyclobutane is going to be costly in processing steps, and I respect that if Russia gave up on their cyclopropyl rocket fuel when costs had to included in their rocket program, then virtually any other hydrocarbon would have a difficult time to compete with kerosene on a cost per payload basis.
If the board were to apply the same standard to this topic, then not being a chemist would never be sufficient for not providing a shred of input. I doubt anyone thought cyclobutane could be dimerized. If cyclobutane is being asked to join together, give at least one other example or principle that would even suggest this to be a reasonable reaction. Once you do that, I think you will find a number of chemists will be happy to help you do a cost estimate from the raw material costs, reagents, reactions, and yields.
I faced this challenge working in the agchem industry. If a farmer could buy weed control for $15/acre, then if you had a herbicide that you need to apply 1 lb/acre, you need to be able to make it for $7.50/lb in order to make a profit. That will limit you to very simple compounds. However, if you only needed 0.1 lb/acre, then you could be profitable if you could prepare it for $75/lb. There is no magic to know your compound has to be extremely potent in order to compete on a cost basis. Here, the competition is crude oil. You distill it a couple of times.