Formaldehyde is produced industrially by the catalytic oxidation of methanol following this reaction: CH3OH → HCHO + H₂ A certain manufacturing plant aims for a production rate of 900 kg/h of formaldehyde. To achieve this, a single pass conversion was maintained at 60%. The product from the catalytic reactor is separated into two streams. The first stream is a mixture of formaldehyde and hydrogen which is removed from the process. The second stream is pure methanol that is recycled to the reactor. Determine the rate of recycled methanol and the rate of the fresh methanol needed (kmol/h).

What are the four elements of corrosion cell ? Give brief description for each of the element.

If a batch rectifier and a batch stripper be combined what advantage is gained?

a. Discuss the relative importance. Is it very important, somewhat important or not important? b. How does the viscosity of a polymer affect the printability and the print quality? c. What is a typical range of viscosity for successful 3-D printing?