Lignin is an organic substance found in cell structures and fibers of wood and plants. It is the second richest renewable source of carbon on Earth after cellulose. Sulfur-containing lignin is commercially used for emulsions, dispersing agents, polymer binders, and food additives. It is also used for agricultural soil rehabilitation, as an anti-corrosion agent, and as a tanning agent.
Lignin is an essential organic binding element in the cell structures and fibers of wood and plants such as grasses. There are two classes of lignin, namely the sulfur-containing and sulfur-free types, which collectively represent the second most abundant source of renewable carbon in the world. As of 2011, however, only sulfur-containing lignin is used commercially, with the vast majority discarded as waste. Common industrial uses of lignin include emulsions and dispersing agents, polymer binders, and food additives. It is also used for agricultural soil rehabilitation, as an anti-corrosion agent and as a tanning agent.
The cells, vessels and fibers of wood and grasses are bound together by an organic substance known as lignin. This essential substance is unique in that its chemical composition is never exactly the same from plant to plant, with the only predictable characteristic being a dendritic network polymer based on phenylpropene. The substance is also notable for being the second richest renewable source of carbon on Earth after cellulose. There are two basic classes—sulfurous lignin and sulfur-free lignin—with the sulfurous variant being the only one of commercial interest as of 2011. In fact, very little substance is used, with most of the 40 million tons (50 – 36.3 million tons) produced annually destined for non-commercial landfill.
The two commonly used sulfur lignin varieties are lignosulfonates and Kraft lignins, with a combined global production of approximately 600,000 metric tons (544,310 tons) per year. One of the desirable characteristics of these substances is their hydrophilic and hydrophobic qualities, which sees the substances used as multipolar dispersants and emulsifiers. As a naturally branched and cross-linked polymer, it is also regularly used as a binding agent in a range of materials, such as polyurethane, polyester, and different grades of particle board and resin. Other industrial uses of the substance as a material binder include the manufacture of composites, activated carbons and various epoxies.
The agricultural sector also uses lignin as an aid to soil rehabilitation and as a component in slow-release fertilizers. Other agricultural uses include components in insecticides, artificial humus, and as an aid for granulation and pelletizing. The food industry is also a consumer of lignin as a component in a variety of antioxidant and antibacterial food additives. In other industries, the substance is often used as a tanning agent, foam stabilizer and component in various antibacterial and anti-inflammatory pharmaceutical preparations.
Protect your devices with Threat Protection by NordVPN
