> If the cost were the same and the processing energy the same, wouldn’t it be better for the climate to bury that plastic (sequestering the carbon) instead of recycling it?
Even if it pollutes more to make virgin material than to recycle it -- and I think that's your problem -- if the non-recycled material goes into a landfill instead of the ocean or biosphere, there's a small consolation in that the carbon in the plastic is sequestered.
I don’t think it’s a small effect. There are something like 300 million tons of plastic waste per year, which is about 1 Gigatonne of CO2, or about 3% of global emissions… more than global aviation!
If we cut down all sources of emissions to zero, that would mean humanity using non-fossil plastic (like PLA or electrolytic syngas derived regular plastics) would be carbon negative.
The cost of PLA is about $2/kg, or equivalent to about $600/tonneCO2. About how much Climeworks currently costs for direct air CO2 capture.
Even if it pollutes more to make virgin material than to recycle it -- and I think that's your problem -- if the non-recycled material goes into a landfill instead of the ocean or biosphere, there's a small consolation in that the carbon in the plastic is sequestered.