Global commercial production of lignin is a consequence of papermaking. In 1988, more than 220 million tons of paper were produced worldwide. Much of this paper was delignified; lignin comprises about 1/3 of the mass of lignocellulose, the precursor to paper. It can thus be seen that lignin is handled on a very large scale. Lignin is an impediment to papermaking as it is colored, it yellows in air, and its presence weakens the paper. Once separated from the cellulose, it is burned as fuel. Only a fraction is used in a wide range of low volume applications where the form but not the quality is important.