a) A hydrocarbon fuel (containing no atomic oxygen) is burned with air. The flue gas composition on a dry basis is 1.0 mol% CO, 6.5 mol% CO2, 8.0 mol% O2, and 84.5 mol% N2. Calculate the ratio of atomic hydrogen to carbon in the fuel and speculate what the fuel may be. Calculate the percentage excess air fed to the reactor.
b) Three thousand kilograms per hour of a solid industrial waste containing 10%w/w of a toxic organic compound is treated using a two stage solvent extraction. The waste is mixed with a recycled solvent stream (containing 1%w/w of the dissolved toxic compound) in the first stage extractor before being separated by gravity settlement. Solvent, containing 4%w/w of the toxic compound and no solid material, is decanted from the settler. The settled sludge is fed to the second stage extractor, where it is mixed with 10,000 kg h-1 of pure solvent and again separated by gravity settlement. The decanted solvent from the second stage extractor is recycled to the first stage, and the settled sludge from the second stage extractor is collected for further treatment. If the settled sludge from both separators contains 60%w/w solvent (on a toxic compound free basis), determine the fraction of the toxic compound that is removed from the waste in each extraction stage