How can convert CO2 into o2 by a machines?

Answer 1

CO2 is released as part of an exothermic (energy-yielding) reaction. Thus, to turn it into something else would take the same, or more energy than you got originally by burning it.

The most efficient reaction to yield 02 from c02 is:

6CO2 + 6H2O = C6H12O6 + 6O2

(Photosynthesis)

However, there are many other chemical reactions to do the same thing, many of which ave been explored. The best solution appears to be to collect C02 from of the atmosphere and convert it into petroleum products (such as fuels) therefore reducing the need for more fossil fuels to be burned or used while creating a product in the process, such as plastics. This has also been explored an demonstrated.

Fortunately nature has it's own mechanisms for mediating c02 levels. 'Global Warming" is a natural cycle which ends in global cooling, humanity does have the potential to overwhelm the current setup, however, but not unless our output at least doubles. Water vaper is the most abundant and acting greenhouse gas. If you do a Google search for converting c02 into 02 you will find several processes which you might be able to power with heat produced from solar panels, but you regardless of how you do it, you'll still be forming some kind of other waste that may or may not be useful, where that cycle of reusing products end is up to you. Good luck, but I would just plant some trees instead. The higher the C02 concentration, the larger the plant can grow (as with the opposite in insects and probably animals), and the more C02 it will remove. Currently the ocean removes the most C02, the vast majority of which is not produced by humans, but it's total consumption is close to being overwhelmed by our own output.