About Lignin

Lignin is an organic substance binding the cells, fibres and vessels which constitute wood and the lignified elements of plants, as in straw. After cellulose, it is the most abundant renewable carbon source on Earth. Between 40 and 50 million tons per annum are produced worldwide as a mostly non commercialized waste product.

It is not possible to define the precise structure of lignin as a chemical molecule. All lignins show a certain variation in their chemical composition. However the definition common to all is a dendritic network polymer of phenyl propene basic units.

There are two principal categories of lignin: those which are sulphur bearing and those which are sulphur-free. It is the sulphur bearing lignins which have to date been commercialized. These include lignosulphonates (world annual production of 500,000 tons) and Kraft lignins (under 100,000 tons p.a.). Due to the lack of suitable industrial processes, the sulphur-free lignins are as yet non-commercialized.

Cross section; lignin impregnated wood

Examples for typical structures in lignin's chemical formula

As a natural and renewable raw material, obtainable at an affordable cost, lignin's substitution potential extends to any products currently sourced from petrochemical substances. The areas in which lignin is applicable include:

Multi-polarity related products
Materials
Agriculture
High purity / value applications
Miscellaneous

Multi-polarity related products

Lignin contains both hydrophilic and hydrophobic groups. Specific treatments can strengthen either characteristic for particular applications as in emulsions and dispersants.

Dispersion

Ceramics
Oil well drilling
Clay bricks & tiles
Cements
Concrete
Gypsum board
Dyestuffs
Electrolytes
Paper sizing

Emulsion

Wax
Asphalt
Bitumen
Vitamins
Micronutrients

Others

Complexing agents
Flocculating
Heavy metal binders
Ion exchange
Water softening
Protein coagulants
Destabilization of oil emulsions
Corrosion protection
Anti-scaling
Metal cleaners
Grinding aids

Materials

Lignin is a natural branched and crosslinked network polymer which lends itself to use in materials.

Phenolic resins
Polyurethanes
Epoxides
Particle boards
Resin boards
Rubber reinforcing
Bloc copolymers
Polyesters
Composites
Polyolefin
Biodegradables
Carbon sieves
Activated carbons
Carbon fibres
Heat resistance
Antioxidants
Anti-inflammation
Paper bounding

Agriculture

Lignin and lignin derived products play an important role in the formation of soils and in plant and animal nutrition.

Soil rehabilitation
Slow release fertilisers
Artificial humus
Fertiliser encapsulation
Composting aid
Manure treatment
Humus improvement
Soil stabilisation
Insecticides
Granulation
Pelletising
Chelates

High purity / value applications

High purity support materials or active substances: lignin can be used as support materials for food and cosmetic applications comprising gels or emulsifiers; specially prepared lignins are suitable as an active substance with anti-oxidant, anti-bacterial and anti-viral properties. These qualities have already been explored and could play an important role in the future.