Cellulose is a derivative of two natural substances: wood and cotton. In plants, it performs an important function, giving them flexibility and strength.
Where is the substance found?
Cellulose is a natural substance. Plants are able to produce it on their own. Contains: hydrogen, oxygen, carbon.
Plants produce sugar under the influence of sunlight, it is processed by cells and enables the fibers to withstand high loads from the wind. Cellulose is a substance involved in the process of photosynthesis. If sugar water is sprinkled on a cut of a fresh tree, the liquid is quickly absorbed.
Pulp production begins. This natural method of obtaining it is taken as the basis for the production of cotton fabric on an industrial scale. There are several methods by which pulp of various qualities is obtained.
Production Method 1
Obtaining cellulose occurs naturally - from cotton seeds. The hairs are collected by automated mechanisms, but a long growing period is required for the plant. Cloth produced in this way is considered the purest.
Pulp can be obtained more quickly from wood fibers. However, the quality is much worse with this method. This material is suitable only for the manufacture of non-fiber plastic, cellophane. Also, artificial fibers can be produced from such material.
Natural Receiving
Producing 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 pulp production. The assembled parts are subjected to high pressure heating. 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 needs to be washed. For this, chlorine is used, which also bleaches. The composition of cellulose with this method is the purest (99%).
Production method 2 from wood
To obtain 80-97% of pulp, coniferous wood chips and chemicals are used. The whole mass is mixed and subjected to temperature treatment. As a result of cooking, the required substance is released.
Mixed calcium bisulfite, sulfur dioxide and wood pulp. 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 is being cleaned.
Get a mass resembling low-quality paper. This material serves as the basis for the manufacture of substances:
- Ethers.
- Cellophane.
- Viscose fiber.
What is produced from valuable material?
The structure of cellulose is fibrous, which makes it possible to make clothes from it. The cotton material is 99.8% natural product obtained by the natural method above. It can also be used to make explosives as a result of a chemical reaction. Cellulose is active when acids are applied to it.
Properties of cellulose are applicable to the production of fabrics. So, artificial fibers are made from it, resembling natural fabrics in appearance and touch:
- viscose and acetate fibers;
- faux fur;
- copper ammonia silk.
Mainly made from wood pulp:
- varnishes;
- photographic film;
- paper products;
- plastics;
- dishwashing sponges;
- smokeless powder.
As a result of a chemical reaction from cellulose get:
- trinitrocellulose;
- dinitrofiber;
- glucose;
- liquid fuel.
In food, cellulose can also be used. Some plants (celery, lettuce, bran) contain its fibers. It also serves as a material for the production of starch. We have already learned how to make thin threads from it - an artificial web is very strong and does not stretch.
The chemical formula of cellulose is C6H10O5. It is a polysaccharide. It is made from:
- medical cotton;
- bandages;
- tampons;
- cardboard, chipboard;
- food additive E460.
Virtues of substance
Pulp can withstand high temperatures up to 200 degrees. The molecules do not break down, which makes it possible to make reusable plastic dishes from it. At the same time, an important quality is preserved - elasticity.
Cellulose withstands prolonged exposure to acids. Absolutely insoluble in water. Not digested by the human body, used as a sorbent.
Microcrystalline cellulose is used in alternative medicine as a digestive cleanser. The powdered substance acts as a food additive to reduce the calorie content of the meals consumed. This helps to eliminate toxins, reduce blood sugar and cholesterol.
Manufacturing Method 3 - Industrial
At production sites, pulp is prepared by cooking in various environments. The material used depends on the type of reagent - type of wood:
- Resinous rocks.
- Decidated trees.
- Plants.
There are several types of cooking reagents:
- Acidic environment. Otherwise, the method is referred to as sulfite. As a solution, a s alt of sulfurous acid or its liquid mixture is used. With this production option, cellulose is isolated from coniferous species. Fir and spruce are well processed.
- The alkaline medium or soda method is based on the use of sodium hydroxide. The solution well separates cellulose from plant fibers (corn stalks) and trees (mainlyhardwood).
- The simultaneous use of sodium hydroxide and sodium sulfide is used in the sulfate method. It is widely introduced into the production of white liquor sulfide. The technology is quite negative for the environment due to the resulting third-party chemical reactions.
The last method is the most common because of its versatility: pulp can be obtained from almost any tree. However, the purity of the material is not quite high after one boil. Impurities get rid of additional reactions:
- hemicelluloses are removed with alkaline solutions;
- Lignin macromolecules and their destruction products are removed with chlorine followed by treatment with alkali.
Nutritional value
Starch and cellulose have a similar structure. As a result of the experiments, it was possible to obtain a vital product from inedible fibers. He needs a person constantly. The food you eat is more than 20% starch.
Scientists managed to obtain amylose from cellulose, which has a positive effect on the state of the human body. At the same time, glucose is released during the reaction. It turns out waste-free 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 removed with the liquid.
Types of substance on sale
Suppliers offer different quality pulp at reasonable prices. We list the main types of material:
- Sulfate white cellulose, produced from two types of wood: coniferous and hardwood. There is unbleached material used in packaging material, poor quality paper for insulating materials and other uses.
- Sulfite also available in white, made from coniferous trees.
- White color powder material suitable for the production of medical substances.
- Premium grade cellulose is produced by bleaching without chlorine. Conifers are taken as raw materials. The wood pulp consists of a combination of spruce and pine chips in a ratio of 20/80%. The purity of the resulting material is the highest. It is suitable for making sterile materials used in medicine.
Standard criteria are used to select the appropriate pulp: material purity, tensile strength, fiber length, tear resistance index. The chemical state or aggressiveness of the aqueous extract medium and humidity are also quantitatively indicated. For pulp supplied as bleached stock, other parameters apply: specific volume, brightness, freeness, tensile strength, purity.
An important indicator for the mass of cellulose is the tear resistance index. The purpose of the materials produced depends on it. The type of wood used as raw material and humidity are taken into account. Also importantresin and fat levels. Powder uniformity is important for certain manufacturing processes. For similar purposes, the toughness and bursting strength of the material in the form of sheets are evaluated.
