Design calculation for multiple component distillation is done by
(A) Ponchon-Savarit method
(B) McCabe-Thiele method
(C) Enthalpy concentration method
(D) Tray to tray calculations
Description : McCabe-Thiele method (A) Uses molal units for material and energy balance (B) Uses weight fractions to express liquid and vapour composition (C) Can use any type of units (D) Is more accurate than Ponchon-Savarit method
Last Answer : (A) Uses molal units for material and energy balance
Description : Which of the following assumes constant molal vaporisation and overflow? (A) McCabe-Thiele method (B) Ponchan-Savarit method (C) Enthalpy concentration method (D) Plate absorption column
Last Answer : (A) McCabe-Thiele method
Description : In distillation column design, the McCabe-Thiele procedure is inadequate and a Ponchan-Savarit procedure is needed, when (A) Saturated feed is not used (B) An azeotrope forms (C) The latent ... vaporisation of the more and less volatile components are greatly different (D) A total condenser is used
Last Answer : (D) A total condenser is used
Description : Pick out the correct statement. (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of ... Flash distillation is suitable for separating components which have very close boiling temperature
Last Answer : (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of nonideal binary system by distillation
Description : In McCabe-Thiele method of theoretical plate calculation for a distillation column, the operating lines of stripping and rectifying sections coincide with the diagonal at __________ reflux. (A) Total (B) Minimum (C) Operating (D) Maximum permissible
Last Answer : (A) Total
Description : Pick out the wrong statement. (A) Different solids have different equilibrium moisture curves (B) Total condenser or reboiler is considered equivalent to one theoretical plate in McCabe-Thiele method of ... (D) Even a forced draft cooling tower cannot cool water below the wet bulb temperature
Last Answer : (C) Heat removal load on cooler remains constant, even with increase of the reflux ratio in a distillation column
Description : Ponchon-Savarit method analyses the fractional equipment based on (A) Enthalpy balance only (B) Material balance only (C) Both enthalpy and material balances (D) The assumption of constant molal-overflow
Last Answer : (C) Both enthalpy and material balances
Description : Pick out the correct statement. (A) The slope of the stripping line is always less than unity (B) For a given separation in a binary distillation column, with increase in reflux ratio ( ... (D) Kremser-Brown-Souder's equation is used to calculate the efficiency of a plate tower
Last Answer : C) In Ponchon-Savarit method of no. of theoretical plate determination, the stripping and rectifying operating lines are vertical at total reflux
Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity
Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer coefficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s
Description : McCabe-Thiele method of binary distillation does not assume that the (A) Sensible heat changes are negligible compared with latent heat changes (B) Molar latent heats of all components are equal (C) Heat of mixing is negligible (D) None of these
Last Answer : (D) None of these
Description : If f = moles of vapour present per mole of feed, then the slope of feed line is (McCabe-Thiele method) (A) (1 - f)/f (B) - (f - 1)/f (C) -1/f (D) -f/(1 - f)
Last Answer : (C) -1/f
Description : In McCabe-Thiele method, at infinite reflux ratio (A) The overhead product is minimum (B) Both the operating lines coincide with diagonal (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (A) The overhead product is minimum
Description : In McCabe-Thiele method, at infinite reflux ratio (A) Number of plates is maximum (B) Overhead product is maximum (C) Both the operating lines coincide with the diagram (D) None of these
Last Answer : (C) Both the operating lines coincide with the diagram
Description : Which of the following unit operations makes use of Thiele-Geddes equation? (A) Liquid-liquid extraction (B) Solid-liquid extraction (C) Multi-component absorption with chemical reaction (D) Multi-component distillation
Last Answer : (D) Multi-component distillation
Description : The assumption made in Elis method in distillation is that enthalpy concentration lines of vapor and liquid are (A) Parallel (B) Straight (C) Both parallel and straight (D) Neither parallel nor straight
Last Answer : (C) Both parallel and straight
Description : Which of the following methods of depreciation calculations results in book values greater than those obtained with straight line method? (A) Multiple straight line method (B) Sinking fund method (C) Declining balance method (D) Sum of the years digit method
Last Answer : (B) Sinking fund method
Description : In extractive distillation, solvent is (A) Added to alter the relative volatility of the mixture (B) Of high volatility (C) Present in overhead stream (D) Of high viscosity to give high tray efficiency
Last Answer : (A) Added to alter the relative volatility of the mixture
Description : Entrainer used in Azeotropic distillation should (A) Form a low boiling azeotrope with one of the constituents of the mixture (B) Form a new azeotrope of low relative volatility with one of the ... (C) Have high latent heat of vaporisation (D) Have high viscosity to provide high tray efficiency
Last Answer : (A) Form a low boiling azeotrope with one of the constituents of the mixture
Description : Small dia distillation column can be a (A) Packed column (B) Sieve tray (C) Bubble cap (D) Any of these
Last Answer : (A) Packed column
Description : In distillation columns, the number of bubble caps per tray primarily depends upon the (A) Allowable liquid velocity (B) Allowable gas velocity (C) Allowable gas and liquid velocities
Last Answer : (C) Allowable gas and liquid velocities
Description : Tray spacing in a distillation column of dia 10-12 ft. used in petroleum refinery may be around __________ inches. (A) 5 (B) 30 (C) 60 (D) 100
Last Answer : (B) 30
Description : Back-trapping in a distillation column (A) Increases tray efficiency (B) Decreases tray efficiency (C) Reduces pressure drop (D) Is desirable, as it provides improved vapour-liquid contact
Last Answer : (B) Decreases tray efficiency
Description : Weeping in a distillation column (A) Increases tray efficiency (B) Provides large interfacial surface for mass transfer (C) Results due to very high gas velocity (D) Results due to very low gas velocity
Last Answer : (D) Results due to very low gas velocity
Description : Concentration of hydrogen peroxide is done by (A) Crystallisation (B) Vacuum crystallisation (C) Atmospheric distillation (D) Dehydration
Last Answer : (B) Vacuum crystallisation
Description : Multiple calculations can be made in a single formula using...... a. Standard Formula b. Array Formula c. Complex Formulas d. Smart Formula
Last Answer : b. Array Formula
Description : Multiple calculations can be made in a single formula using…… a. Standard Formula b. Array Formula c. Complex Formulas d. Smart Formula
Description : Which component is mainly responsible for doing calculation in computer ? (1) Random access memory (2) Control unit (3) Arithmetic logic unit (4) Hard disk
Last Answer : ALU (Arithmetic logic unit)
Description : The partial molar enthalpy of a component in an ideal binary gas mixture of composition Z, at a temperature T and pressure P, is a function only of (A) T (B) T and P (C) T, P and Z (D) T and Z
Last Answer : (B) T and P
Description : The McCabe ΔL law states that the (A) Molar heats of vaporisation of components are nearly equal (B) Linear crystal growth rate depends on the degree of super-saturation (C) Linear ... does not depend on the crystal size (D) Linear crystal growth rate depends on the crystal size
Last Answer : (C) Linear crystal growth rate does not depend on the crystal size
Description : The change in enthalpy per unit weight of adsorbed gas when adsorbed on gas free or "outgassed" adsorbent to from a definite concentration of adsorbate is called its (A) Integral heat of adsorption (B) Heat of wetting (C) Differential heat of adsorption (D) Heat of normal condensation
Last Answer : (A) Integral heat of adsorption
Description : The change in enthalpy, when a unit quantity of gas is absorbed by relatively large quantity of adsorbent (on which a definite concentration of the adsorbed gas already exists) is termed as the (A) ... (B) Heat of wetting (C) Integral heat of adsorption (D) None of these
Last Answer : (A) Differential heat of adsorption
Description : Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a (A) Straight line (B) Sine curve (C) Parabola (D) Hyperbola
Last Answer : (A) Straight line
Description : Large scale drying of sugar is done in a __________ dryer. (A) Spouted bed (B) Tray (C) Rotary (D) Truck
Last Answer : (C) Rotary
Description : Large scale drying of wheat is done in a __________ dryer. (A) Fluidised bed (B) Spouted bed (C) Tray (D) Vacuum rotary
Last Answer : (B) Spouted bed
Description : The main use of heavy gas oil produced by the vacuum distillation unit is as a (A) Blending component for kerosene (B) Blending component for petrol (C) Feedstock for fluid catalytic cracking unit (D) None of these
Last Answer : (C) Feedstock for fluid catalytic cracking unit
Description : Langmuir equation is associated with (A) Leaching (B) Adsorption (C) Steam distillation (D) Multi-component absorption
Last Answer : (B) Adsorption
Description : In distillation, overhead product contains (A) Only one component (B) Two components (C) Any number of components (D) Only saturated liquid
Last Answer : (C) Any number of components
Description : Fenske equation for determining the minimum number of theoretical stages in distillation column holds good, when the (A) Relative volatility is reasonably constant (B) Mixture (to be separated) ... (to be separated) shows positive deviation from ideality (D) Multi-component distillation is involved
Last Answer : (A) Relative volatility is reasonably constant
Description : With lapse of time, the overhead composition of light component in case of batch distillation with constant reflux (A) Increases (B) Decreases (C) Remain same (D) May increase or decrease; depends on system
Last Answer : (B) Decreases
Description : Use of packed towers for distillation is generally limited to the (A) Small sizes (B) Multi-component distillation (C) High pressure operation (D) Vacuum distillation
Last Answer : (A) Small sizes
Description : The Hatta number is important in (A) Multi-component distillation (B) Binary distillation (C) Gas absorption without chemical reaction (D) Gas absorption with chemical reaction
Last Answer : (D) Gas absorption with chemical reaction
Description : Flash distillation is (A) Same as differential distillation (B) Used for multi-component systems like crude refining (C) Same as simple distillation (D) Most useful for handling binary systems
Last Answer : (B) Used for multi-component systems like crude refining
Description : Steam distillation is used to (A) Reduce the number of plates (B) Avoid thermal decomposition of a component (C) Increase the efficiency of separation (D) Increase the total pressure of distillation
Last Answer : (B) Avoid thermal decomposition of a component
Description : steam distillation, the (A) Temperature is 100°C(B) Temperature is more than 100° C (C) Product must be immiscible with water (D) Temperature is higher than the boiling point of either component
Last Answer : (C) Product must be immiscible with water
Description : Light oil whose major component is Benzol, is obtained by the distillation of crude tar in the temperature range of __________ °C. (A) 80-170 (B) 200-300 (C) 250-270
Last Answer : (A) 80-170
Description : What is the Thiele modulus of the solid catalysed first order reaction as shown in the bellow figure, if the pore diffusion offers negligible resistance to reaction? (A) < 5 (B) < 0.5 (C) > 1 (D) 5
Last Answer : (B) < 0.5
Description : If Thiele modulus is __________, then the pore diffusion resistance in a catalyst may be considered as negligible. (A) 0 (B) ∞ (C) < 0.5 (D) > 0.5
Last Answer : (C) < 0.5
Description : For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to (A) 0 (B) 1 (C) 0.1 (D) 0.5
Last Answer : (C) 0.1
Description : Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric ... (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these
Description : Effectiveness factor (E) of a catalyst pellet is defined as, E = (actual rate within pore of the catalyst)/(rate if not snowed by pore diffusion), Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus) (A) tan hT/T (B) tan T/T (C) tan hT/tan T (D) None of these
Last Answer : (A) tan hT/T