
	Trending ▼ ICSE CBSE 10th ISC CBSE 12th CTET GATE UGC NET Vestibulares ResFinder

2003 Course Reaction Eng. - II

3 pages, 18 questions, 0 questions with responses, 0 total responses,

	pune_eng	+Fave Message
	Profile Timeline Uploads Q & A

Home > pune_eng >

Instantly get Model Answers to questions on this ResPaper. Try now!
NEW ResPaper Exclusive!

Formatting page ...

Total No. of Questions : 8] [Total No. of Pages :3 [3864] - 363 B.E. (Petrochemical) REACTION ENGINEERING - II (2003 Course) P1161 Time : 3 Hours] [Max. Marks : 100 Instructions to the candidates: 1) Answer any three questions from each section. 2) Answer to the two sections should be written in two separate answer books. 3) Figures to the right indicate full marks. 4) Assume suitable data wherever necessary. 5) Use of electronic calculator is allowed. SECTION - I Q1) A catalytic reaction A 2 R is studied in a plug flow reactor using various amounts of catalyst and 20 lit/hr of pure A feed at 3.2 atm and 117oC. The following data is recorded. Run No. 1 2 3 4 5 W kg cat 0.020 0.040 0.080 0.120 0.160 0.074 0.060 0.044 0.035 0.029 CA out mol/lit Calculate weight of the catalyst needed for 55% conversion of A in a) Isothermal fixed bed reactor and b) An isothermal fluidized bed reactor both operating at 117oC for feed flow rate of 2000 m3/hr and feed containing 40% of A at 7atm total pressure. [18] Q2) a) b) Gas phase catalytic reaction A + B <=> 2 R takes place in the presence of an inert carrier material I that can get adsorbed on the catalyst surface without poisoning it. Find the rate expression when surface reaction controls. [8] Discuss in brief a method each for measuring surface area and bulk voidage of a porous catalyst. [8] P.T.O. Q3) Laboratory data collected on a first order catalytic decomposition of A is over a particular catalyst is given below. Examine the data and give your estimates on. [16] a) Relative proportion of external and internal mass transport resistances. b) Maximum possible temperature difference across the gas film. c) Maximum possible temperature difference along the pellet radius. Data: dp = 2.5 mm De = 2.3 x 10-5 m3/hr m cat (effective diffusivity) keff = 0.55 kcal/hr m cat oK (effective thermal conductivity) h = 90 kcal/hr m2 cat oK (heat transfer coefficient). Kg = 150 m3/hr m2 cat (mass transfer coefficient) HR= -100 kcal/mol A (exothermic heat of reaction) C Ag = 20 mol/m3 (bulk gas concentration of A) " -r Aobs = 5 x 105 mol/hr m3 cat (observed rate). Q4) a) b) A first order catalytic reaction 2 A products is taking place along with slow first order ( and concentration independent) deactivation of the catalyst. Derive relationship between concentration of A and time for the case of Batch solids Mixed constant flow of fluid. [8] Describe in adequate detail different mechanisms of deactivation of catalysts. [8] SECTION - II Q5 Derive conversion-time relationships for a gas -solid non-catalytic reaction for the following control regimes: [16] a) Constant size spherical solid particle with reaction controlling the overall rate. b) Shrinking solid sphere (small enough in size to assume Stoke s regime) with external mass transport controlling the overall rate. Q6) Explain with reference to gas-liquid reactions. a) b) c) Design for minimum tower height in case of an instantaneous reaction between gas and liquid reactants. [6] Suitability of employing liquid side reaction for mass transport enhancement in case of very high and very low Henry s constant systems. [4] Choice of reactors for gas-liquid reactions. [6] [3864] - 363 -2- Q7) An impurity A in a gas is to be reduced from 3.5% to 1 ppm by counter current contact with an aqueous solvent containing a reactant B. The reaction A + 2B product is almost instantaneous. What incoming concentration of B would give the minimum height of tower? What is this height? [16] Data: KAg a = 10000 mol/hr m3 atm. KAl a = KBl a = 0.65/hr. G = 2 x 105 mol/hr m2 L = 9 x 105 mol/hr m2, HA = 2.7 x 10-3 atm m3/mol. Q8) Write notes. a) Reactors for refinery conversions. [6] b) Models for nonideal flow. [6] c) Design of non-adiabatic fixed bed reactor. [6] ***** [3864] - 363 -3-

Formatting page ...

Tags : Pune, Engineering, University of Pune, Engineering question papers, Pune University, previous year question papers, question papers, india, model question paper, pune university paper pattern, pune university syllabus, old question papers

pune_eng chat

Horizontal lines at:
Guest Horizontal lines at:
AutoRM Data:
Box geometries: