The chemistry of recycling involves the treatment of commercial products to remove and isolate components for reuse in other products. The materials most commonly recycled are paper products, metals, glass, and plastics.

Nearly one third of all newspapers, as well as very large quantities of magazines and corrugated cardboard, are recycled. Newsprint consists principally of cellulose fibers, binders, and other additives to improve the appearance and feel of the paper and inks. The objective of paper recycling processes is to recover the cellulose fiber and to eliminate or greatly disperse the ink. This is accomplished either by a series of washing and filtration steps or by pressure-steaming the paper.

Nearly half of the metal produced in the United States is recycled metal scrap, the majority of which is from automobiles. Recycling iron scrap saves nearly 0.75 of the energy required for steel production with a concomitant reduction in air...