Answer:
According to the Environmental Paper Network's Paper Calculator, it takes about 32 million BTUs of energy to produce 1 ton of virgin paper fiber. To produce 1 ton of recycled paper, it takes about 22 million BTUs.
so the answer could be it takes less Btu to manufacture recycled products than new ones
CH4+2O2–>CO2+2H2O
4Fe+3O2–>2Fe2O3