Formaldehyde serves as an organic raw material for the synthesis of various end products in numerous applications. In addition to the chemical industry, formaldehyde is also frequently used in the pharmaceutical industry. Typical synthesis products include resins, dyes, fertilizers, disinfectants, pesticides, and pharmaceuticals.
Formaldehyde is produced by the oxidation of methanol. The two most important production processes offer different advantages and disadvantages. Due to its higher efficiency and lower residual methanol content, the silver process has now replaced the metal oxide process. However, more frequent catalyst regeneration is advisable here.
With the robust LiquiSonic® measurement technology the synthesis can be monitored inline and the methanol and formaldehyde content can be determined precisely.
Application
Formaldehyde is predominantly produced on an industrial scale using the silver process. In this process, methanol gas is mixed with air and passed over silver electrodes, which act as a catalyst. This produces formaldehyde gas, which is precipitated with water and collected as a liquid.
The excess methanol is recovered and returned to the process, with a residual amount of less than 1 wt% remaining in the formaldehyde to stabilize it. The LiquiSonic® measurement technology is used to identify the finished intermediate product and ensure the quality of the final product. Time-consuming laboratory measurements, which only provide analysis values with a delay, are eliminated. Process efficiency can be derived from the precisely determined inline concentrations.
Installation
The LiquiSonic® measurement technology is installed directly in transport lines to determine the concentrations of the intermediate and final product inline. The LiquiSonic® Controller 40 is connected to the LiquiSonic® ultrasonic sensor as well as the measuring unit for the second physical variable (density). In the main view, the controller displays the concentration of formaldehyde as well as methanol.
Typical measuring range:
Methanol concentration: 0 - 5 wt%
Formaldehyde concentration: 40 - 60 wt%
Temperature: 60 - 80 °C
