Download SGBAU (Sant Gadge Baba Amravati university) B-Tech/BE (Bachelor of Technology) 8th Sem Chemical Engineering Chemical Reaction Engineering II Previous Question Paper
11675 : Chemical Reaction Engineering-II : 8 CH 02
P. Pages : 4 AW - 3493
. . lli?lll?? J
Time . Thxee Hours . o 3 1 2 . Max. Marks : 80
Notes : 1. Answer three question from Section A and three question from Section B.
2. Due credit will be given to neamess and adequate dimensions.
3. Assume suitable data wherever necessary.
4. Diagrams and chemical equations should be given wherever necessary.
5. Illustrate your answer necessary with the help of neat sketches.
6. Discuss the reaction, mechanism wherever necessary.
7. Use of pen BluerBlack ink?refill only for writing the answer book.
SECTION - A
l. a?) A pulse input to a vessel gives the results shown in Fig. 7
3) Check the material balance with the tracer curve to see whether the results are
consistent.
b) If the result is consistent, determine T. V and sketch the E curve.
AI-lmolatl=o
u - 4 Mers/min
b') A batch of radioactive material is dumped into the Columbia River at Hanhord, Washington. 7
At Bonneville Dam. about 400 km dmmstream the ?owing waters (6000 m?fs) are monitored
for a particular radioisotope ([1,? >10 yr) and the data of F ig. are obtained.
a) How many units of this tracer were introduced into the river?
b) What is the volume of Columbia River waters between Bonneville Dam and the point
of introduction of tracer?
C, units of
radioaclimtylrn3
20 35125
OR
AW - 3493 1 133110
, u?-..
?JI
8)
b.)
AW - 3493
Dispersed noncoalescing droplets (C A0 = 2mol / liter) react 7
(A -?> R.?rA = kCzA .k : 0.51iter / mol.min) as they pass through a contractor. Find the
average concentration of A remaining in the droplets leaving the cuntactor if their RTD is
given by the curve in Fig.
1, mm
Explain the ?tting the Dispersion model for small Iixtents of dispersion, D/uL < 0.01 and 7
large deviation from plug 110w. Dqu 2 0.01.
The concentration of reactants and products for the reaction A (g) + 38(5) '~ solid produm for 13
a particle of unchanging size. use SHRINKING-CORE MODEL FOR SPI?IERICAL
PARTICLES OF UNCHANGING SIZE. Obtain the rclatinnship oftime with radius and With
conversion in which the
a) Chemical Reaction controls. b) Ash layer controls.
OR
Hydrogen sul?de is rcmm ct! from (Dill gas b} passing the gas through a moving bed 01? iron 13
oxide particles. In the cm] gas em ironmcnt (L'onxidcr uniform) the solids are com exted
from Fe: ()3 t0 FeS by the SCM?reuction commit 1? = 1 hr. Find the fractional conversion
ofc-xide to iron sul?de ifthc R'I?I) nf solids in the reactor is approximated by the E curves
of
30 ' " " 90min
1n 2: Fluid-Fluid Reactions discuss the eight special czmes. that is from in?nitely fast to very 13
slow reaction. Obtain the rate equation for case.
B. (In?nitely fast reaction with high Ca.)
OR
We wish to lower the concentmtion of B in the liquid (VI : 1.62 m3,Cu = 55555.6 mol / m3) 13?
of an agitated tank reactor b) bubbling gas (Pg =?)00l)mol/hr. 1::105Pa)containing A
(Pmn =1000Pa) through it. A and B react as follows:
A(g ~> l)+B(]).?+ product(l)?IX'= kCACB.
a) How long must we bubble gas through the vessel to lower the concentration from
CBO =555.6 to C81? :=55.6moixm3?
I~J
a)
b)
c.)
a)
b)
b) What percent of entering A passes through the vessel unreacted?
Additional data
K Aga = 0.72m01/hx-1113-Pa fl = 0.9m31iquid/m3 total
KMa=l44hr?1 DA=DB=3.6x10'6m2/hr, a=100 m2/m3
HA =103Pa-m3/moi k=2.6x105m3/mol-hr
CT: 55555.5 muma
C30 - 555.6 mollm3 at i = 0
c8 = 55.6 mollma at .m. .. ?
:::1%%0P:??Vh' V, = 1.62 m3
pk. u. = 1000 Pa
SECTION ? B
Explain the method for determination of Surface Area of catalyst. 14 .
Explain the concept ofcatalyst deactivation.
De?ne Promoters & Inhibitors in solid catalysts.
0R
Explain the method for determination ofpore volume of a catalyst particle. 7
A hydrogenation catalyst is prepared by soaking alumina particles (100 to 150 mesh size) in 7
aqueous NiNO5 Solution. After drying and reduction the particles contain about 7 wt %
MD. This catalyst is then made into large cylindrical pellets for rate studies. The gross
measurements for one pellet are
Mass = 3.15 g
Diameter = 1.00 in
Thickness = I in
Volume ?- 3.22 cm3
The A12 03 particles contain micropores. and the pelleting process introduces maeroporcs
surrounding the particles. From the experimental methods already described the macropore
volume of the pellet is 0.645 cm3 and the micropore volume is 0.40 cm3/g of particles. From
this information calculate:
a) The density of the pellet.
b) The macropore volume in cubic centimeters per gram.
c) The macropore void fraction in the pellet.
d) The micropore void fraction in the pellet.
The following kinetic data are obtained in an experimental Carbcrry type basket reactor 13?
using lOOgm of catalyst in the paddles and different ?ow rates from run to run 2
A ?'R FAOvaU min 0.14 0.42 1.67 2.5 1.25
CAo='?m??m? CA.m01/m3 8 6 4 2 1
AW - 3493 3 P.T.0
10.
11.
12.
Detzrmine the amount nt'catalyst needed in a packed bed reactor for 75% conversion of
1000 m0] A?min of a ('N. =8 mo] "m3 feed.
OR
The cataly?c reaction 13
A -?> 4R
is studied in a plug ?ov? reactor using various amounts ofcatalyst and 20 lilers/hr ofpurc A
feed at 3.2 aun and 1 l7"?(,?. The concentrations of A in the ef?uent stream is recorded for the
various runs as follows.
Run 1 2 3 4
Chlalyst used. kg 0.020 0.040 0.080 0.160
CAN? . mnl" lilcr 0.074 0.060 0.044 0.029
Find the rats equation for Ihis reaction. using the integral method ofanalysis
Thc ?rsl?ordcr decompnshinn of A is run in an experimental mixed ?ow reactor. Find the 13
role played by pore diffusion in these runs; in effect determine whether the runs were made
under diffusiou-?'cc. strong resistance. or intermediate conditions.
dp VV' CAO V XA
3 4 75 10 0.2 A ?-> R
1 6 100 5 0.6
OR
'l'ht? following kinetic data on the reaction A ?) R are obtained in an experimental packed 13
bed reactor using various amounts (:fcatalysl and a ?xed feed rate PM = 10k mull hr.
megggm _ 1? ?.2; . 3 4 5 F 6 7
7):;77 7 ?.012 i 0.20 ? 0.27 0.33 0.37 0.41 1 (14f;
l?inj the reaction ratc? at 40? 'n comersion.
In ccsigning a large packed bed reactor \\ ith feed rate FAQ = 400 k moL hr ho? much catalyst
would be needed far 40?}. cunvcrsion.
***************
AW ? 3493 4
This post was last modified on 10 February 2020