a) Say we want to purify benzene from p-xylene using a distillation column at 12 bar...

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a) Say we want to purify benzene from p-xylene using a distillation column at 12 bar and we start with a liquid mixture of 40/60 benzene to p-xylene by mole. First find out what the temperature is that the first bubble of vapour would appear from this mixture (the bubble point). As a starting point a colleague tells you that at this higher pressure, the distillation columns operates around 230 degrees Celsius. Note that for this first part the use of a spreadsheet (such as Excel) or even better an iterative solver (such as Excel's solver add-in) may be helpful. You will have to do external research to find any physical property information needed for solving this problem. Include these physical properties values in your solution and state where you found them. Also state how you went about solving this, showing key equations you use and how you used these. You do not need to provide the Excel file, but can state how you set up equations and the results these yielded. b) In this same column, a final vapour product exits the top of column consisting of 95 mol % of the more volatile substance (you tell me which substance this is). What is the temperature required to turn this vapour product stream entirely into a liquid - this again represent the bubble point. (generally it is easier to move liquids in a plant as they take up less volume). Again, you do not need to provide the Excel file, but can state how you set up equations and the results these yielded. c) Still in the same column, a liquid product exits the bottom of the column with 90 mol% of the less volatile substance. If this exits the column at 250 C, at what pressure will this liquid stream become entirely a vapour? This represents the dew point, meaning the point where a vapour mixture forms its first drop of liquid. Again, you do not need to provide the Excel file, but can state how you set up equations and the results these yielded. a) Say we want to purify benzene from p-xylene using a distillation column at 12 bar and we start with a liquid mixture of 40/60 benzene to p-xylene by mole. First find out what the temperature is that the first bubble of vapour would appear from this mixture (the bubble point). As a starting point a colleague tells you that at this higher pressure, the distillation columns operates around 230 degrees Celsius. Note that for this first part the use of a spreadsheet (such as Excel) or even better an iterative solver (such as Excel's solver add-in) may be helpful. You will have to do external research to find any physical property information needed for solving this problem. Include these physical properties values in your solution and state where you found them. Also state how you went about solving this, showing key equations you use and how you used these. You do not need to provide the Excel file, but can state how you set up equations and the results these yielded. b) In this same column, a final vapour product exits the top of column consisting of 95 mol % of the more volatile substance (you tell me which substance this is). What is the temperature required to turn this vapour product stream entirely into a liquid - this again represent the bubble point. (generally it is easier to move liquids in a plant as they take up less volume). Again, you do not need to provide the Excel file, but can state how you set up equations and the results these yielded. c) Still in the same column, a liquid product exits the bottom of the column with 90 mol% of the less volatile substance. If this exits the column at 250 C, at what pressure will this liquid stream become entirely a vapour? This represents the dew point, meaning the point where a vapour mixture forms its first drop of liquid. Again, you do not need to provide the Excel file, but can state how you set up equations and the results these yielded.

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To solve these problems we need to use thermodynamic properties of benzene and pxylene The key property we need is the vaporliquid equilibrium VLE dat... View the full answer