Activated Carbon Drying for Corrosion-Free Phosgene Production
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of phosgene is challenged by corrosion damage to plant components, hydrochloric acid formation, and solid deposits at the reactor outlet, which are exacerbated by using a moist activated carbon catalyst.
Innovation Solution
Drying the activated carbon catalyst by reducing its water content through an inert gas stream, monitoring moisture levels via dew point measurement, and switching to reaction gases when desired moisture is reached, ensuring drying down to a dew point of -20°C.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a moist activated carbon catalyst is used in phosgene production, then the catalyst is easier to handle and store, but corrosion damage to plant components, hydrochloric acid formation, and solid deposits occur
Solution Approach 1:
The catalyst is dried in advance before being introduced into the reactor to remove harmful moisture. This preliminary action prevents corrosion and hydrochloric acid formation during the phosgene production process, while the dried catalyst maintains acceptable handling properties through controlled drying conditions
2Object-affected harmful factors
If the catalyst is dried to very low moisture levels, then corrosion and hydrochloric acid formation are prevented, but the drying process becomes more complex and time-consuming
Solution Approach 1:
A moisture detection device monitors the moisture content of the catalyst during drying and provides feedback control. The drying process automatically terminates when the moisture content reaches a predetermined threshold level, preventing both over-drying and under-drying. This feedback mechanism simplifies the drying process by eliminating the need for complex manual monitoring and adjustment procedures
3Object-affected harmful factors
If the catalyst is dried to very low moisture levels, then corrosion and hydrochloric acid formation are prevented, but the drying time and resources increase
Solution Approach 1:
The moisture detection device provides real-time monitoring and automatic termination of the drying process when the predetermined moisture threshold is reached. This prevents unnecessary extended drying time while ensuring sufficient moisture removal to prevent corrosion and hydrochloric acid formation during phosgene production
Solution Approach 2:
The drying process parameters (temperature, gas flow rate) can be adjusted to optimize the drying rate while achieving the target moisture content. By controlling these parameters, the drying time is minimized while still achieving the necessary moisture reduction to prevent harmful effects
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This process prevents corrosion, reduces hydrochloric acid formation, and enhances catalyst activity, allowing for longer reactor lifetimes and reduced cleaning efforts.
Implementation Method 1
The invention relates to a process for the production of phosgene by gas phase reaction of carbon monoxide and chlorine in the presence of a catalyst, in particular in the presence of an activated carbon catalyst, in which the catalyst is dried by reducing the water content
Implementation Method 2
Contacting the catalyst with an inert gas stream; Determining the residual moisture of the catalyst by determining the moisture in the exhaust gas stream
Data Source
Figure 1~2
AI summary
The invention relates to a method for producing phosgene by reacting chloride and CO on an active carbon catalyst, characterized in that the active carbon catalyst is dried by reduction of the water content, the drying comprising the following steps: a) bringing the catalyst into contact with an inert gas stream, b) determining the residual humidity of the catalyst by determining the humidity in the exhaust gas stream, c) completing the drying process after reaching the desired humidity in the exhaust gas stream by changing from the inert gas to the reaction gases, and optionally d) heating the catalyst bed and/or the inert gas during the drying process.