During the Bleaching reactions that occur are as follows:
1. Pelarutan chlorine in the water
CaOCl2 → Ca(OCl)2 + CaCl2
2. Calcium hypochlorite terhidrolisa
Ca(OCl)2 + H2O → Ca(OH)2 + 2HOCl
3. At the same time, the gas also occurred chlor
CaCl + Ca(OCl)2 + H2O ↔ Ca(OH)2 + CL2
4. Acid happens to work hypochlorite bleach fiber
On + HOCl → HCl
5. CO2 from the air to accelerate decomposition
Ca(OH)2 + CO2 → CaCO3 + H2O
Bleaching process in order to walk slowly to be done in an atmosphere of alkali with the addition of Sodium Carbonate (Na2CO3). In PH alkali HOCL there are a few Bleaching so that the process is running slowly. The possibility of damage due to fiber oxidation can be prevented.
Bleaching is usually done on PH alkali. During the process of PH will drop because there is the influence of CO2 from the air, therefore, to maintain the PH plus buffer buffer solution.
Ca salt contains chlorine that may settle in the material and will menyebabakan rough grip, for example, CaCO3, which formed because of the influence of CO2 from the air / Ca (OH) 2. To avoid this done pengelantangan information (scouring) with HCl. The remnants of chlorine that still exist in the material will become so HOCl give effect pengelantangan information.
ReactionCaCO3 + 2HCl → CaCl2 + H2CO3
CaOCl2 + HCl → CaCl2 + HOCl
Ca(OH)2 + 2HCl → CaCl2 +H2O
During the process of removing the chlorine Bleaching chlorine gas are absorbed into some of the material. Chlorine gas is very dangerous if konsentrasinya large. After drying, although the amount of chlorine gas, but little konsentrasinya become larger, so will damage the fibers, which resulted in decreased strength. Therefore, after Bleaching with the need to further process with the anti-chlor Sodium sulfit, Bisulfir, or hidrosulfit to tie chlor that may exist in the material
ReactionNaHSO3 + CL2 + H2O → NaHSO4 + 2HCl
NaS2O4 + 3Cl + 4H2O → 2NaHSO4 + 6HCl
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