Yes, this process is very energy intensive and generates like twice CO2 per energy used. But in a hypothetical world without oil and natural gas it may lead to earlier start with electric cars and renewables so the total amount of CO2 put into atmosphere would probably be the same. Plus, as coal is much more evenly distributed, there would be much less reasons for wars.
Then in a hypothetical scenario of 20th century without oil/natural gas nuclear energy would be much more widespread at this point and CO2 impact would be lower.
You could probably do it with carbohydrates (starches, sugars) or related molecules (wood, alcohol). But I'm pretty sure that hydrocarbons is what you intended there, and it's easier to dig that out of the ground.