Chemical Engineering Answers

What is sphericity?

NMR spectrum of CH3-CH(OCH2CH3)2

NMR spectroscopy of CH3-CH(OCH3)2

CaCO3 precipitate is made by reacting CaO with an aqueous solution of Na2CO3, the by-product being NaOH. After decanting, slurry leaving the precipitation tank is 5% w/w CaCO3, 0.1% NaOH, and the balance water. 100 000 kg hr–1 of slurry is fed to a two-stage counter-current continuous washing system to be washed by 200 000 kg hr–1 of fresh water. Underflow from each unit contains 20% w/w solids. Calculate fraction of NaOH recovered and mass percentage NaOH of dried product. Would adding a third stage be worthwhile? 

An ideal gas is undergoing a process in which temperature and volume relation is Tav-25 Calculate the work done by the gas is going from state -1 in which pressure is 100 bar and the volume is 4 m to a state-2 in which the volume is 2 m. Also calculate the pressure at the state-2 of the system. 

What are the major petrochemicals processes to form the intermediate compounds (second generation petrochemicals), with examples?

Use the Peng-Robinson equation of state to calculate the binary interaction coefficient (k12) of a {2 + (X × 0.5)} 

m3

vessel that contains {30 + (0.15 × Y)} kg of propane mixed with {50 + (Z × 0.3)} kg of n-butane at 30 bar and 

450 K.

𝑃 =

𝑅𝑇

𝑉 − 𝑏𝑚𝑖𝑥

−

𝑎𝑚𝑖𝑥

𝑉2 + 2𝑏𝑚𝑖𝑥𝑉 − 𝑏𝑚𝑖𝑥

2

𝑓𝑜𝑟 𝑒𝑎𝑐ℎ 𝑝𝑢𝑟𝑒 𝑐𝑜𝑚𝑝𝑜𝑛𝑒𝑛𝑡: 𝑎 = 0.45724

𝑅

2𝑇𝑐

2

𝑃𝑐

× [1 + (0.37464 + 1.54226𝜔 − 0.26992𝜔

2

)(1 − 𝑇𝑟

0.5

)]

2

𝑎𝑚𝑖𝑥 = ∑𝑖 ∑𝑗 𝑥𝑖𝑥𝑗𝑎𝑖𝑗 𝑎𝑖𝑗 = (𝑎𝑖𝑎𝑗)

0.5

(1 − 𝑘𝑖𝑗)

𝑓𝑜𝑟 𝑒𝑎𝑐ℎ 𝑝𝑢𝑟𝑒 𝑐𝑜𝑚𝑝𝑜𝑛𝑒𝑛𝑡: 𝑏 = 0.07780 𝑅𝑇𝑐

𝑃𝑐

CPT 307 ASSIGNMENT

The Figure below shows a cross section through an insulated heating pipe which is made from steel (k = 45 W / m K) with an inner radius of 150 mm and an outer radius of 155 mm. The pipe is coated with 100 mm thickness of insulation having a thermal conductivity of k = 0.06 W / m K. Air at Ti = 60°C flows through the pipe and the convective heat transfer coefficient from the air to the inside of the pipe has a value of hi = 35 W / m2 K. The outside surface of the pipe is surrounded by air which is at 15°C and the convective heat transfer coefficient on this surface has a value of ho = 10 W / m2 K. Calculate the heat loss through 50 m of this pipe. 

A fuel is analyzed and found to contain; 75.0 wt% methane, 10.0% ethane, 5.0% ethylene and the balance water. The flowrate of the fuel is 102.7 kg/h. Calculate the molar composition of this gas on both a wet and a dry basis and the ratio(mol H2O/ mol dry gas). If tgis fuel is to be burned with 28% excess air, what is the required air feed rate (kmol/h)? How would the answer change if the combustion were only 40% complete?

1 kg of ait at 1 bar 15 degree centridage is compressed reversibly and adiabtically in a pressure of 4 bar.Calculate the final temperature and the work input.