The use of space time is preferred over the mean residence time in the
design of a/an
(A) Batch reactor
(B) Ideal tubular-flow reactor
(C) Slurry reactor
(D) CSTR

1 Answer

Answer :

(B) Ideal tubular-flow reactor

Related questions

Description : For reactions in parallel viz A → P (desired product) and A → Q (unwanted product), if the order of the desired reaction is higher than that of the undesired reaction, a (A) Batch reactor is preferred over a ... a single CSTR for high yield (C) Both (A) and (B) (D) Single CSTR is the most suitable

Last Answer : (C) Both (A) and (B)

Description : Space time equals the mean residence time (A) When the density of the reaction mixture is constant (B) For large diameter tubular reactor (C) For narrow diameter tubular reactor (D) For CSTR

Last Answer : (A) When the density of the reaction mixture is constant

Description : Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a ... ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction

Last Answer : (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty

Description : A reactor is generally termed as an autoclave, when it is a (A) High pressure batch reactor (B) Atmospheric pressure tank reactor (C) High pressure tubular reactor (D) Atmospheric pressure CSTR

Last Answer : A) High pressure batch reactor

Description : Pick out the wrong statement. (A) 'Hold back' is defined as the fraction of material that stays longer than the mean residence time (B) Study of non-ideal flow reactor is done experimentally ... final stages of reaction (D) A batch reactor cannot be used to study the kinetics of catalytic reaction

Last Answer : (D) A batch reactor cannot be used to study the kinetics of catalytic reaction

Description : Backmixing is most predominant in (A) A well stirred batch reactor (B) A plug-flow reactor (C) A single CSTR (D) CSTR's connected in series

Last Answer : (C) A single CSTR

Description : For the same residence time, which one will give the maximum conversion? (A) Single stirred tank (v = 5 litres) (B) Two stirred tank (each of 2.5 litres) in series (C) Stirred tank followed by tubular flow reactor (each of 2.5 litres) (D) Single tubular flow reactor (v = 5 litres)

Last Answer : (D) Single tubular flow reactor (v = 5 litres)

Description : An isothermal irreversible reaction is being carried out in an ideal tubular flow reactor. The conversion in this case will __________ with decrease in space time. (A) Increase (B) Increase exponentially (C) Decrease (D) Remain unchanged

Last Answer : (C) Decrease

Description : Pick out the wrong statement. (A) For a first order consecutive reaction, a tubular flow reactor as compared to a stirred tank reactor provides higher overall selectivity(B) For an ideal ... D) Reaction rate does not decrease appreciably as the reaction proceeds in case of an autocatalytic reaction

Last Answer : (A) For a first order consecutive reaction, a tubular flow reactor as compared to a stirred tank reactor provides higher overall selectivity

Description : In a semi-batch reactor, (A) Mixing takes place in axial direction only (B) Velocity of reaction can be controlled (C) Condition similar to plug flow reactor exists (D) Residence time is constant

Last Answer : (B) Velocity of reaction can be controlled

Description : In a semi-batch reactor (A) Velocity of reaction can be controlled (B) Maximum conversion can be controlled (C) Both the reactants flow counter-currently (D) Residence time is constant

Last Answer : (A) Velocity of reaction can be controlled

Description : For nearly isothermal operation involving large reaction time in a liquid-phase reaction, the most suitable reactor is a __________ reactor. (A) Stirred tank (B) Tubular flow (C) Batch (D) Fixed bed

Last Answer : (A) Stirred tank

Description : For an ideal mixed flow reactor (CSTR), the exit age distribution E(t) is given by (A) A Dirac delta function (B) A step function (C) A ramp function (D) None of the above

Last Answer : (D) None of the above

Description : The exit age distribution curve E(t) for an ideal CSTR with the average residence time, τ, is given by (A) e -t/τ (B) e -t/τ /τ (C) 1 - e -t/τ (D) 1 - (e -t/τ /τ)

Last Answer : (B) e -t/τ /τ

Description : The residence time distribution of an ideal CSTR is (A) (1/τ) exp (-t/τ) (B) τ exp (-t/τ) (C) exp (-t/τ) (D) (1/τ) (-t/τ)

Last Answer : (C) exp (-t/τ)

Description : Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor

Last Answer : (B) Tubular flow reactor

Description : Sometimes, batch process is preferred over continuous process, when the product (A) Quality & yield cannot be achieved in continuous processes, because of long residence time (B) Sales demand is fluctuating (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : Batch process is preferred over continuous process, when the (A) Product yields and quality cannot be achieved in continuous process, because of long residence time (B) Sales demand of product is not steady (C) Same ... be used for several processes of the same nature (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

Description : Batch process is preferred over continuous process, when the (A) Product yields and quality cannot be achieved in continuous process, because of long residence time (B) Sales demand of product is not steady (C) Same ... cannot be used for several processes of the same nature (D) All (A), (B) & (C)

Last Answer : (B) Sales demand of product is not steady

Description : Oil is hydrogenated using nickel catalyst in a __________ reactor. (A) Batch (B) Slurry (C) Fluidised bed (D) Fixed bed

Last Answer : (B) Slurry

Description : For a packed bed reactor; the presence of a long tail in the residence time distribution curve is an indication of: (A) Ideal plug flow (B) Bypass (C) Dead zone (D) Channelling

Last Answer : (C) Dead zone

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Description : . A batch reactor is characterised by (A) Constant residence time (B) Variation in extent of reaction and properties of the reaction mixture with time (C) Variation in reactor volume (D) Very low conversion

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Description : In an ideal tubular-flow reactor (A) There is no mixing in longitudinal direction (B) Mixing takes place in radial direction (C) There is a uniform velocity across the radius (D) All (A), (B) and (C)

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Description : Recycling back of outlet stream to the reactor from an ideal CSTR carrying out a first order liquid phase reaction will result in __________ in conversion. (A) Decrease (B) Increase (C) No change (D) Either (A) or (B), depends on the type of reaction

Last Answer : (C) No change

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Last Answer : (D) Back-mix

Description : Space time in flow reactor is (A) Usually equal to the residence time (B) The reciprocal of the space velocity (C) A measure of its capacity (D) Both (A) and (B)

Last Answer : (D) Both (A) and (B)

Description : Space velocity (A) Describes the extensive operating characteristics of a tubular flow reactor (B) Is the maximum feed rate per unit volume of reactor for a given conversion (C) Is a measure of the ease of the reaction (D) All (A), (B) and (C)

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Description : Exothermic reactions are best carried out in (A) A CSTR (B) CSTR in series (C) A plug flow reactor followed by CSTR (D) CSTR followed by a plug flow reactor

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