Use the following atomic masses of elements: Carbon: 12; Hydrogen: 1; Oxygen: 16. 1 Maleic anhydride (C4H2O3) is produced by the vapour phase reaction of benzene with air (take as 21% oxygen and 79% nitrogen). The fresh feed of benzene has the following composition: 99% w/w benzene, 1% w/w toluene. The vapour phase catalysed reaction takes place isothermally in a fluidised bed reactor. The reactor operates at 75% conversion per pass of benzene. Assume there is no oxygen in the reactor outlet. - - The reactor efflux is cooled and partly condensed and then (ideally) separated into two streams: a gas stream containing all the nitrogen, carbon dioxide, toluene and the unreacted benzene and a liquid stream containing the maleic anhydride and water. Assume the gas stream is cooled further and all the nitrogen and carbon dioxide leave the process, the benzene and toluene remain in the liquid phase. Part of this liquid stream is recycled, but 5% is purged to avoid a build-up of toluene. (a) What is the chemical equation for the production of maleic anhydride? [2 marks] (b) Draw a block diagram and annotate the streams for your mass balance. [4 marks] (c) Based on a feed of 100 kmol h1 calculate the molar flowrate of each component in each stream. Verify that the overall mass balance is satisfied. [12 marks] (d) From the calculated rate and composition of the purge stream, suggest two possible ways to utilise the species contained in it. [2 marks]