How to Produce Rayon From Cellulose
- 1). Purify the cellulose material by mixing bamboo or wood pulp with sodium hydroxide. The caustic soda should have a maximum temperature of 25°C. Press the resultant pulp to attain a weight above the original pulp by combining it with an alkali.
- 2). Treat the purified product with carbon sulfide. After treatment, this results into a yellow crumb referred to as xanthenes belonging to the ester group. This is carried out in temperatures ranging between 20 °C and 30 °C.
- 3). Dissolve the yellow crumb in the caustic soda solution that is 15 to 20 °C in temperature to form a viscous substance. Filter the viscous mixture. Leave the filtered mixture with desired fiber that is insoluble.
- 4). Allow for the viscous mixture to mature so that cellulose contained in it is transformed into a more uniform substance. This step can be further enhanced through filtration of the viscous material to get rid of insoluble materials that may interfere with the subsequent production process.
- 5). Remove gas from the viscous material so as to prevent weak points and obtain more refined rayon.
- 6). Pass the viscose through the spinneret that contains sulphuric acid, sodium sulphate and zinc sulphate. This results in fine rayon as the mixture undergoes coagulation.
- 7). Stretch the cellulose to create parallel filaments that can be used as textile fibers. This is referred to as drawing.
- 8). Wash the rayon to get rid of impurities. Cut the rayon material into desired lengths. This helps in preparing the rayon material for its various uses such as garment and fabric manufacture.
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