Urea Formaldehyde Concentrate (UFC) Production Process
Over 20 million metric tons of urea-formaldehyde are created each year. The forest products sector uses more than 70% of this production to connect particleboard, MDF, hardwood plywood, and laminating glue. Briefly speaking, the first step in forming formaldehyde is the reaction between methanol and air. The urea formaldehyde concentrate created after this stage dissolves into the urea solution. It is also worth mentioning that each Urea Formaldehyde Concentrate (UFC) manufacturer utilizes a specific method to make a particular grade of this substance. Hence, production methods vary based on their details and their outcome.
Below, we go into detail about this chemical compound production process. In the method described in this article, formaldehyde and urea are transformed into a stable liquid product that contains 60% or more, preferably 80 to 85%, total solids (calculated as formaldehyde and urea plus the remaining water) and that is soluble at room temperature. This process produces a dependable formaldehyde concentrate that is particularly useful for creating slow-release nitrogen fertilizers. It is also suitable for making adhesives.
The Raw Materials
One of the starting components is an aqueous formaldehyde solution that ranges from 30 to 50%. An unfettered (low methanol) formaldehyde solution with no more than 0.02% by weight of formic acid based on the formaldehyde is an excellent choice. Solid urea or aqueous urea can be used in the procedure, too. It is more suitable if manufacturers utilize urea that contains no more than 0.015% of ammonia by weight of the total amount of urea.
The Description of the Process
The procedure entails adding urea to an aqueous formaldehyde solution that contains between 30 and 50% by weight of formaldehyde and, preferably, no more than 0.02% by weight of formic acid. The aqueous must have no more than 0.015% by weight of ammonia, in such a quantity that the resultant combination contains a mol ratio of 4.4 to 7.3 mols of formaldehyde for every mol of urea. It then raises the reaction mixture’s pH to a value between 8.8 and 9.5, ideally 8.8 to 8.9, before heating it to a temperature between 30 and 60 degrees Celsius.
By distillation at temperatures between 45° and 60°C, water should be removed from the combination above for at least 15 minutes, ideally 0.5 to 1.0 hours. This process must occur at a pressure lower than atmospheric, at which water is removed from the mixture and evaporated, leaving behind a liquid composed primarily of formaldehyde and urea, which account for 60 to 90% of the liquid residue. The duration of heating the reaction mixture and evaporating the water correlates with the reaction and evaporation temperatures. Ultimately, there should be 2 to 3 urea-formaldehyde molecular species in the concentrated aqueous urea-formaldehyde reaction product. Additionally, this product must have a buffer capacity of 7 to 10.