Example 2.1 Evaluate the profit margin for the HDA process. From Tables 8.3 and 8.4, the following prices for raw materials and products are found: Benzene = $0.919/kg Toluene = $1,033/kg Natural gas (methane and ethane, MW = 18) = $11.10/GJ = $11.89/1000 std. it' = $0.302/kg Hydrogen = $1.000/kg (based on the same equivalent energy cost as natural gas) Using 1 kmol of toluene feed as a basis 4-83. Determine the resultant couple moment of the two couples that act on the pipe assembly. The distance from A to B is d = 400 mm. Express the result as a Cartesian vector