Lignocellulosic biomass

The lignocellulose (from Latin lignum = " wood " or "tree" ) is the cell wall of woody plants and serves them as a structural scaffold. First hemicelluloses and primarily cellulose form a framework in which the process of lignification ( lignification ) subsequently the lignin is stored.

Molecular structure

Cellulose is a polymer of a number of elongated β -1 ,4- glycosidically linked glucose - monomers. A variety of these polymers is assembled into fibers with partially crystalline regions. These fibers are arranged along the xylem and give the plant thus high train and flexural strength. Hemicellulose makes up a smaller proportion and is structured less ordered. Reason is that this polymer consisting of various sugars also branching has linkages that do not allow fiber- like arrangement. Lignin consists of various types of phenylpropanoids, which are incorporated into the cellulose - hemicellulose - lignin backbone and linked to the polymer. The two substances are thus closely linked and form the lignocellulose.

Function

Often compared to the reinforced concrete is used to describe the function of lignocellulose. While the cellulose, comparable to the steel reinforcement, train for strength and flexural strength ensures that matrix of lignin, as analogous to concrete, the compressive strength is responsible. For example, if a tree heavily loaded in a storm, the cellulose fibers provide on the windward side for tensile strength. On the leeward side of the Lignineinlagerungen prevent the collapse of the non- solid wood structure by imparting compressive strength. In addition, lignocellulose is not easily accessible due to its dense structure and linkage of enzymes and protects the woody plant against pests such as fungi and bacteria.

Use

The use takes place in the form of wood as a building material and fuel. The cellulose fraction is used for paper making. Lignin is a waste and impurity, which should be present in the lignocellulose used in as small a quantity. In several pilot projects lignocellulose will be used for grain, straw, reed, wood, paper and cellulose-containing waste as a renewable raw material for different chemical raw materials tried. In particular, the phenylartigen compounds in the lignin are considered as potential raw material for recycling. The use of lignocellulose as a raw material for biofuels is aimed at the production of lignocellulosic ethanol. Corresponding manufacturing processes are currently in development or industrial testing.