# Problem 4You have developed a genetically engineered strain of a methanotroph bacteria (a bacteria that feedson methane) that produces formaldehyde, a compound used in a variety of medical applications, and forthe storage and preservation of biological tissue samples. The two main metabolic reactions involvingmethane (relevant enzymes not shown) are:CH4O2HCHO H20CH4 202 CO2 2H20You cultivate these bacteria in a bioreactor by feeding 100 mol/s of a 50 mol% methane, 50mol% oxygenstream, and recover the produced formaldehyde from the effluent.on extents of reaction toa) Draw and label a flowchart of the process. Use a DOF analysis badetermine how many process variable values must be specified for the remaining variables to becalculatedb) Derive expressions (equations) for the product stream flow rates in terms of extents ofreactionsc) If the fractional conversion of methane is 0.9 (i.e. 90% of the incoming methane is consumed),and the fractional yield of formaldehyde is 0.855 (i.e. 85.5% of methane entering the system isconverted to formaldehyde), calculate the molar composition (mol fraction of each component)of the reactor output stream.

Question
check_circle

Step 1

Let n1 to n5 represent the molar flowrate of components in outlet stream.

The reactions taking place inside the reactor are as shown andlet x1 and x2 represent the extent of reaction for reaction 1 and 2 respectively.

Step 2

Degree of freedom is given as in equation 1

DOF= (Number of unknowns) - (Total number of independent equations) – Equation 1

In the given problem there are 7 unknowns-  , n2, n3, n4, n5, x1, x2

The number of independent equations is equal to number of species in the system. Since there are 5 species the number of equations possible are 5.

Step 3

Part b

Product stream flow rates in terms of extent of reaction are given from equation 2 ...

### Want to see the full answer?

See Solution

#### Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in