Lignin: Functional Biomaterial with Potential in Surface Chemistry and Nanoscience - The Nanoscience and Technology of Renewable Biomaterials - page 196

7.6 Lignin: Current and Future Uses

Starting from about the beginning of the 1920s, lignin has been prepared for use in larger
scales and as a raw material to produce other chemicals (McCarthy and Islam 2000). In
the beginning lignosulfonates from sulfite spent liquors were processed at industrial plants
to make vanillin and lignin preparations. In 1936 the Marathon Corporation began the
production of leather tanning agents and dispersants from lignosulfonates. Some years
later, in 1942, West Virginia Pulp and Paper Company (Westvaco) started to produce
kraft lignin products from softwoods and hardwoods. Some of these products (Indulin A
and C) were sold to the rubber, ceramic, and printing ink industries. In the late 1940s,
Puget Sound Pulp and Timber Co began the production of a fermented lignosulfonate
product, Lignosite, which was 1960 patented in the form of a chrome and ferrochrome
derivative as an additive to oil well drilling muds. For some sulfite mills that sold all
of their produced lignosulfonates, during the mid-seventies and some years beyond the
lignin business was actually more profitable than the pulp business.
In 1990 the world production of lignin products was 138.5 thousand tons per year
(Lin and Zhong 1990). In the latter part of the 1990s, the worldwide amount of
lignin recovered and isolated from pulping processes and later sold totalled 1% of all
the lignin generated. Of this lignosulfonate was the main lignin derivative produced.
Larger companies involved in the production were Fraser Paper Inc., Georgia-Pacific
Inc., Nippon Paper Industries Ltd, LignoTech-USA, Borregaard Lignotech-Norway and
Tembec, Inc. In 1998, the lignosulfonate sold by Georgia-Pacific Inc. alone was 220,000
tons. Borregaard Lignotech-Norway and Westvaco also produced kraft lignin but part
of it was later sulfonated.

The total sales in 1996 were estimated to around USD

600 million.
Lignosulfonates are a very effective and economical adhesive, acting as a binding
agent in pellets or other compressed materials (Lignin Institute 2007). Used on unpaved
roads, lignosulfonate reduce airborne dust particles and stabilize the road surface. This
binding ability makes it a useful component e.g. of coal briquettes, bricks, plywood
and particle board, ceramics, animal feed pellets, carbon black, fibreglass insulation,
fertilizers and herbicides, linoleum paste, soil stabilizers etc. Due to their amphiphilic
nature lignosulfonate also stabilizes emulsions of immiscible liquids, such as oil and
water, making them highly resistant to breaking. Uses as emulsifiers in e.g. asphalt
emulsions, pesticides, pigments and dyes and wax emulsions are common. Metal ions
can be complex bound to lignosulfonates, preventing them from reacting with other
compounds and becoming insoluble. Metal ions sequestered with lignosulfonates stay
dissolved in solution, and are thus available to plants. Scaly deposits in water systems
can also be prevented through this. As a result, they are used in e.g. micronutrient
systems, cleaning compounds and water treatments for boilers and cooling systems.
This high cationic exchange capacity of lignosulfonates lends itself for use in measuring
heavy metals concentrations in sensor applications. Martins et al . (2008) have shown
that lignin films can be well utilised for exactly this application. Recently, Guo et al .
(2008) ranked the cation exchange capacity and found that the metal ion adsorption
is heavily dependent on pH, with higher metal concentrations detected at elevated pH
where some of the phenolic groups become dissociated.