Endpoint control in the intermittent production of sodium hypochlorite
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This post was last edited by sunjl1981 on 2013-1-6 22:09. What is the best method to determine the reaction endpoint when producing sodium hypochlorite using the batch process? :Victory: HP/ORP # + + . hcbbs
Our production is generally monitored based on pH and the specific gravity of the finished product; chlorine addition is stopped once the specified parameters are reached. It is mainly determined based on the ratio of raw materials and the free alkali in sodium hypochlorite at the end of the reaction, and there is indeed a certain basis for this.
We generally make the judgment based on pH and the operator’s experience; once the target values are reached, chlorine addition is stopped, and chemical analysis is then used for confirmation. This post was last edited by limingshuguang on 2008-11-12 19:18.]
The combination of online analysis and chemical analysis, along with the operator’s experience
It is determined by analyzing the free base in the product.
After chlorination, analyze the free base; keeping it between 2-12 g/l is sufficient. If the level is too high, it represents a waste, and customers will not accept it； It’s too low; the decomposition rate is fast, which is not conducive to storage. Last edited by wlntjs on 2008-11-16 09:41.]
We use sampling analysis to control the endpoint of sodium hypochlorite; generally, as sodium hypochlorite approaches its endpoint, it is necessary to reduce the flow rate of chlorine gas to prevent acidification during the production process when it is near the endpoint.
Online ORP can be used for monitoring, with free base serving as the criterion for acceptance; national standards specify this, but the results of free base analysis vary considerably from person to person.
Reply to 8# sirsdj: May I ask if there are any specific ORP analysis instruments available?