DEPARTMENT OF CHEMICAL ENGINEERING JAYPEE UNIVERSITY OF ENGINEERING & TECHNOLOGY, A-B ROAD, RAGHOGARH, DT. GUNA – 473226, M.P., INDIA PRODUCTION OF PHENOL FROM CHLOROBENZENE Shikhar Prakash (101446) Sumit Verma (101449) 1 Production of Phenol from Chlorobenzene
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DEPARTMENT OF CHEMICAL ENGINEERING JAYPEE UNIVERSITY OF ENGINEERING & TECHNOLOGY, A-B ROAD, RAGHOGARH, DT. GUNA – 473226, M.P., INDIA
PRODUCTION OF PHENOL FROM CHLOROBENZENE
Shikhar Prakash (101446)Sumit Verma (101449)
1Production of Phenol from Chlorobenzene
Natural occurrences Natural occurrences:
During fractionation of coal tar, carbonic oil fraction is
separated containing 30-35wt% phenolic components and liquid
byproducts from gasification process.
Applications: Used as an disinfectant in household cleaners and in mouthwash,
used forsynthesis of dyes, aspirin (C9H8O4). Used for making picric acid , Used in the manufacturing of
Bisphenol - A Phenol is also used to produce Aniline
Product specifications & standards
Phenol is classified as a Class B poison.The US Pharmacopeia (USP) specifications for phenol
include:
a) Purity is to be no less than 98 wt%.
b) Clear solubility of 1 part of phenol in 15 parts of water.
c) A congealing temperature to be not lower than 39°C.
d) A content of non volatiles is no more than 0.05 wt%.
Phenol demand forecast in India
Graph 1: Production / Import of phenol in metric ton per year.
2011 2012 2013 2014 20150
50,000
100,000
150,000
200,000
250,000
300,000
DemandProductionImport
Year
Metric tonnes
Plant capacity on demand - supply basis (for 2014)
The most widely accepted technology for producing phenol is cumene oxidation process because of better economics due to by-product acetone. If one wants to avoid acetone, the choice will be toluene oxidation process.
Selected process
Phenol from chlorobenzeneThere aretwo reactions to convert chlorobenzene to phenol using chlorination route:
Causticization
C6H5 Cl+ NaOH → C6H5ONa
NaOH is in aqueous media (Operating conditions: 425°C and 350 atm, Exothermic reaction)
Heat of reaction = Σ Heat of product – Σ Heat of reactant+ ΔH 298
Heat of reaction = -21735942.74 J/mol
Production of Phenol from Chlorobenzene 11
Heat balance across Heat balance across heat exchanger
heat exchanger inlet outlet reactor inlet
Tref = 303 K Tref = 303K,
Tin = 313 K T= 573K
QNaOH = 310595.5465 J Q NaOH = 8342126.471 J
QC6H5Cl = 5449157.38 J QC6H5Cl = 14019901.52 J
Q C12H10O = 45211.0613 J QC12H10O = 1358477.399 J
Heat balance reactor outlet Heat balance neutralizer in
Tref = 303 K, T = 698 K T ref = 303K, T= 333 K
QHCl = 19671615.81 J QHCl = 309069.2717 J
Q C6H5Cl = 1190158.848 J QNaOH = 223550.9719 J
QNaOH =2920034.506 J Q C12H10O = 136762.8128 J
Q C12H10O = 2147280.632 J Production of Phenol from Chlorobenzene 12
QC6H5OH = 3116121.024 J
QNaCl = 115353535.308 J
QC6H5Cl = 111834.3687 J
QNaOH = 372452.6559 J
Q C12H10O = 229770.867 J
Energy balance across distillation column
Assumptions:Temperature of distillate = 460 K
Boiling point of Diphenyl oxide = 531.46 K
Boiling point of phenol =455 K
Feed enters at =353 K
Production of Phenol from Chlorobenzene 13
Production of Phenol from Chlorobenzene 14
Utility required in reactor
Heat of reaction = -21735942.74 J/mol
Cp of water = -75.327 J/mol K
ΔH = n*Cp*dT
-21735942.74 = n*(-75.327)*(40)
n = 7213.861 moles
Weight of water required = 7213.861*18 = 129849.5126 g/hr
Process & mechanical design of neutralizing tank C6H5ONa + HCl C6H5Cl + NaCl EQUIPMENT - Cylindrical vessel with a drain valve and a turbine agitator
Total weight of the reacting mass = 48950.587 kg/h Average density at 60oC= 1.4006 kg/litre Total volume of reacting mass= Total weight of the reacting mixture
Average Density
Let residence time (T) = 2 hours
Vo= mav/dav =34.949 m3/hr
T = V / Vo
V = 69.898 m3
Where V = Volume of reactor
L/D = 1.25
D= 4.14 m, H=5.18 m
Mechanical design The maximum pressure in the tank is 14.70 psi (1
atm)
ts=[{(14.70 x 4.14)/(2 x 20000 x 0.8)}+0.005] x 2.54 =5.13 mm
Take shell thickness= 5mm
Design pressure is above 100 Kpa, ellipsoidal head would be an ideal choice
Major axis: Minor axis=2:1
Inside depth (B=A/2), A=D/2, B=D/4
B=1.035 cm
Volume V of the ellipsoidal head
V = (3.14 x 4.142 x 5.18/4) + (3.14 x 4.143/12) = 88.306 m3
Design of agitator
Let diameter of the agitator= 0.6 x D
Da= 0.6 x 4.14= 2.484 m
Speed of the agitator=75 rpm = 1.2 rps
Average Viscosity =3.6 cp
Average density of the slurry=1.1747 kg/lt
Calculating Reynolds Number Nre
Nre = 112584.00
Calculating Froude number Nfr
Nfr = n2 x Da/g = 1.252 x 2.484/9.81 = 0.3956
1 cm=1/30.8 ft
1 kg/lt= 62 lb/ft3
9.81 m/s2=32.17 ft/s2
Power=[(0.123)-0.0935 x 1.253 x (8.1710)5 x 1.4006 x 62]/32.17
Power=331.52 ft/lbf
Power=0.513 HP
Assuming frictional losses
Power= 1.5 HP
Torque in the shaft=2 x 550/2 π n
Torque in the shaft= 140 ft/lbf
Distillation Column: Process design Feed components:
Costing of distillation columnThickness of shell = 0.06 m
Weight of vessel = = x 10.8 x 0.06 x 7850 = 16292.003 Kg Where r is the internal radius of distillation
column, L is the length of column, t is the thickness of shell.Density of carbon steel = 7850 Kg/m3
Weight of head, skirt = 10% weight of vessel.Total weight of column without tray = 1.1 x 16292.003 = 17921.23 Kg
Production of Phenol from Chlorobenzene 31
Production of Phenol from Chlorobenzene 32
Therefore, Purchased cost of distillation column without trays (1990) = $ 105
Production of Phenol from Chlorobenzene 33
Purchased cost of tray = $ 300 per/trayTotal cost of trays = 18 x $ 300 = $ 5400Quantity factor of each tray = 1.10Total cost of the trays = 1.10 x $ 5400 = $ 5940Total cost of distillation column in 1990 = $ (105 + 5940) =$
105940Cost index in 1990 (C1) = 356 (Chemical engineering plant
cost index refer Klaus D.Timmerhaus Page 163)
Cost index in 1990 (C2) = 588.6 P1 = Purchased cost of distillation column in 1990P2 = Purchased cost of distillation column in 2014 Present Cost = Original Cost P2 =105940 = $ 17518 = Rs 17518 59 = Rs 10,334,327
Production of Phenol from Chlorobenzene 34
Costing of various equipments1. Purchased cost of distillation column = Rs
10,334,3272. Purchased cost of heat exchanger = Rs.
82837363. Purchased cost of Neutralizer = Rs 3217984. Purchased cost of reactor = Rs 29966100
(b) Payback PeriodLand + working capital = 1.12 + 3.67 = 4.8Payback period is the point at which cumulative cash flow is
equal to the sum of land and working capital.Payback period (PBP) = =3+((4.939-4.8)/(4.939-0.77))Therefore, PBP = 3.033 years
(c) Rate of return on investment (ROROI)
Where n is the project life. ROROI = 20.68 %
Production of Phenol from Chlorobenzene 38
Production of Phenol from Chlorobenzene 39
Plant layout
First Aid safety measuresEyes: Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Extensive irrigation with water is required (at least 30 minutes).
Skin: Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse. Discard contaminated clothing in a manner which limits further exposure. SPEEDY ACTION IS CRITICAL! Destroy contaminated shoes.
Ingestion: Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
Inhalation: Get medical aid immediately. Remove from exposure to fresh air immediately. If breathing is difficult, give oxygen. Do NOT use mouth-to-mouth resuscitation. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
Notes to Physician: Persons with liver or kidney disease should not be exposed to phenol for any length of time.
Antidote: Activated charcoal, followed by cathartic, may be preferred to ipecac induced emesis or lavage in decontamination of the GI tract and preventing systemic absorption of phenol.
Production of Phenol from Chlorobenzene 40
Conclusions
After studying the entire process of manufacture of phenol, there are a few recommendations: ◦ Phenol production has a very good scope
in India.◦ For most of the equipments, the fixed
capital investment is higher but the payback period is small.
[9] Dryden C. E., Outlines of Chemical Technology, East-West Press, 2008
[10] Kirk R. E., Othmer D. F., Encyclopedia of Chemical Technology, John Wiley and Sons, 1999-2012
[11] Carl L.Yaws, Chemical Properties Handbook, Tata McGraw Hill publications, Third Edition.
[12] Max S.Peters, Klaus D.Timmerhaus, Plant design and economics fro chemical engineers, McGraw-Hill International editions, chemical and petroleum engineering series, fourth edition.