Cellulose is a derivative of two natural substances: wood and cotton. In plants, it carries out an important function, gives them flexibility and strength.
Where is the substance found?
Cellulose is a natural substance. Plants are able to produce it on their own. The composition contains: hydrogen, oxygen, carbon.
Plants produce sugar under the influence of sunlight, it is processed by cells and enables the fibers to withstand high wind loads. Cellulose is a substance involved in the photosynthesis process. If sugar water is sprayed onto a slice of a fresh tree, the liquid will quickly absorb.
Pulp production begins. This natural way of obtaining it is taken as the basis for the production of cotton fabric on an industrial scale. There are several methods by which cellulose of various quality is obtained.
Manufacturing Method No. 1
Cellulose is produced by a natural method - from cotton seeds. Hair is collected by automated mechanisms, but it takes a long period to grow the plant. The fabric produced in this way is considered the cleanest.
More quickly, cellulose can be obtained from wood fibers. However, with this method, the quality is much worse. This material is suitable only for the manufacture of non-fibrous plastic, cellophane. Artificial fibers can also be made from such material.
Natural receipt
Cellulose from cotton seeds begins with the separation of long fibers. This material is used to make cotton fabric. Small parts, less than 1.5 cm, are called cotton fluff.
They are suitable for the production of cellulose. The assembled parts are heated under high pressure. The duration of the process can be up to 6 hours. Before starting to heat the material, sodium hydroxide is added to it.
The resulting substance must be washed. To do this, chlorine is used, which also bleaches. The composition of cellulose with this method is the purest (99%).
Method of manufacturing No. 2 from wood
To obtain 80-97% of cellulose, coniferous wood chips and chemicals are used. The entire mass is mixed and subjected to temperature treatment. As a result of cooking, the desired substance is released.
Calcium bisulfite, sulfur dioxide and wood pulp are mixed. Cellulose in the resulting mixture is not more than 50%. As a result of the reaction, hydrocarbons and lignins dissolve in the liquid. The solid material goes through a purification step.
Get a mass resembling poor-quality paper. This material serves as the basis for the manufacture of substances:
- Ethers.
- Cellophane.
- Viscose fiber.
What is made from valuable material?
The cellulose structure is fibrous, which makes it possible to make clothes from it. Cotton material is a 99.8% natural product obtained by the natural method described above. Explosives can be made from it as a result of a chemical reaction. Cellulose is active when acids are applied to it.
The properties of cellulose are applicable to the production of fabrics. So, artificial fibers are made from it, resembling the appearance and touch of natural fabrics:
- viscose and acetate fibers ;
- faux fur;
- copper and ammonia silk.
Mostly made from wood pulp:
- varnishes;
- film;
- paper products;
- plastics
- sponges for washing dishes;
- smokeless powder.
As a result of a chemical reaction from cellulose receive:
- trinitrocellulose;
- dinitrocellulose;
- glucose
- liquid fuel.
Cellulose can also be used in food. As part of some plants (celery, lettuce, bran), its fibers are present. It also serves as a material for the production of starch. We have already learned to make thin threads out of it - the artificial web is very durable and does not stretch.
The chemical formula of cellulose is C6H10O5. It is a polysaccharide. From it are made:
- medical cotton wool;
- bandages;
- tampons;
- cardboard, chipboard;
- food supplement E460.
Advantages of the substance
Cellulose can withstand high temperatures up to 200 degrees. Molecules are not destroyed, this allows you to make reusable plastic dishes from it. At the same time, an important quality is retained - elasticity.
Cellulose can withstand prolonged exposure to acids. Absolutely insoluble in water. It is not digested by the human body, it is used as a sorbent.
Microcrystalline cellulose is used in alternative medicine as a drug for cleaning the digestive system. A powdery substance acts as a food supplement to reduce the calorie content of consumed foods. This helps to eliminate toxins, lower blood sugar and cholesterol.
Manufacturing Method No. 3 - Industrial
At the production sites, pulp is prepared by cooking in various environments. The material used depends on the type of reagent - the type of tree:
- Resinous rocks.
- Deciduous trees.
- Plants.
There are several types of cooking reagents:
- Acidic environment. Otherwise, the method is referred to as sulfite. As a solution, a salt of sulfurous acid or its liquid mixture is used. In this production variant, cellulose is isolated from coniferous species. They process fir, spruce well.
- The alkaline medium or soda method is based on the use of sodium hydroxide. The solution separates cellulose well from plant fibers (corn stalks) and trees (mainly deciduous).
- The simultaneous use of hydroxide and sodium sulfide is used in the sulfate method. It is widely introduced in the production of white liquor sulfide. The technology is quite negative for the environment due to the formation of third-party chemical reactions.
The latter method is the most common because of its versatility: cellulose can be obtained from almost any tree. However, the purity of the material is not quite high after one cooking. Impurities are eliminated by additional reactions:
- hemicelluloses are removed with alkaline solutions;
- lignin macromolecules and the products of their destruction are removed by chlorine followed by treatment with alkali.
The nutritional value
Starch and cellulose have a similar structure. As a result of experiments, it was possible to obtain a vital product from inedible fibers. It is required by a person constantly. Food consumed consists of more than 20% starch.
Scientists have managed to obtain amylose from cellulose, which positively affects the state of the human body. At the same time, glucose is released during the reaction. It turns out non-waste production - the last substance is sent for the manufacture of ethanol. Amylose also serves as a means of preventing obesity.
As a result of the reaction, the cellulose remains in a solid state, settling to the bottom of the vessel. The remaining components are removed using magnetic nanoparticles or dissolved and discharged with liquid.
Types of Substances on Sale
Suppliers offer pulp of various quality at affordable prices. We list the main types of material:
- White sulfate cellulose produced from two types of wood: coniferous and hardwood. There is unbleached material used in packaging material, poor quality paper for insulation materials and other purposes.
- Sulphite is also available in white, made from conifers.
- The white powder material is suitable for the production of medical substances.
- Premium cellulose is bleached without chlorine. Coniferous species are taken as raw material. Wood pulp consists of a combination of spruce and pine wood chips in a ratio of 20/80%. The purity of the material obtained is the highest. It is suitable for the manufacture of sterile materials used in medicine.
To select the appropriate pulp, standard criteria are used: material purity, tensile strength, fiber length, tear resistance index. The chemical state or aggressiveness of the aqueous extract medium and humidity are also quantified. For pulp supplied in the form of bleached pulp, other indicators are applicable: specific volume, brightness, grinding value, tensile strength, degree of purity.
Important for the pulp mass is an indicator - the index of tear resistance. The purpose of the produced materials depends on it. The type of wood used as raw material and moisture are taken into account. The level of resins and fats is also important. Powder homogeneity is important for certain processes. For similar purposes, the viscosity and bursting strength of a sheet material are evaluated.