23-Chem-B6 Petroleum Refining and Petrochemicals
Worked solutions to 11 past sittings (2013–2019), 60 questions. Pick a sitting, or start from a topic below.
- December 2019
- December 2018
- May 2018
- December 2016
- May 2016
- December 2015
- May 2015
- December 2014
- May 2014
- December 2013
- Undated paper
Topics across the sittings
Topics that come up in more than one sitting, taken from the headings of our worked solutions. A topic counts once per sitting.
- Gasoline Properties (5 sittings): December 2019 Q1 · December 2015 Q5 · May 2015 Q5 · December 2014 Q4 · December 2013 Q6
- Pour Point (5 sittings): December 2015 Q4 · May 2015 Q6 · December 2014 Q2 · May 2014 Q6 · December 2013 Q5
- API gravity (4 sittings): December 2019 Q2 · May 2015 Q4 · December 2014 Q4 · December 2013 Q2
- Flash Point (4 sittings): December 2015 Q2 · December 2014 Q1 · May 2014 Q4 · December 2013 Q3
- Alkylation (3 sittings): May 2015 Q2 · May 2014 Q2 · Undated paper Q2
- Hydrogen Production (3 sittings): May 2015 Q4 · December 2014 Q5 · December 2013 Q1
- Octane Numbers (3 sittings): December 2015 Q2 · May 2014 Q4 · Undated paper Q3
- Product Specifications (3 sittings): December 2015 Q6 · May 2015 Q3 · May 2014 Q3
- Visbreaking (3 sittings): December 2015 Q3 · May 2014 Q5 · December 2013 Q2
- Acetylene plant (2 sittings): December 2014 Q3 · December 2013 Q6
- Acid-gas removal (2 sittings): December 2014 Q2 · December 2013 Q4
- Atmospheric distillation unit (2 sittings): December 2019 Q4 · May 2016 Q2
- Benzene-Hydrogenation Recycle (2 sittings): May 2015 Q6 · December 2013 Q1
- Carburetion (2 sittings): May 2015 Q1 · May 2014 Q1
- Crude Refining (2 sittings): May 2015 Q3 · May 2014 Q3
Questions by sitting
December 2019
- Question 1: Gasoline properties; binary distillation split
- Question 2: API gravity; evaporator with feed bypass
- Question 3: Petroleum-fraction properties from correlations
- Question 4: TBP curve and the atmospheric distillation unit
- Question 5: Major refining conversion processes
December 2018
- Question 1: Refining terminology; the hydro-processing family
- Question 2: Petroleum coke; hydrogen manufacture and purification
- Question 3: The isomerisation unit (black-box analysis)
- Question 4: Two-column separation of a light hydrocarbon mixture
- Question 5: Estimating petroleum-fraction properties from correlations
May 2018
- Question 1: Refining terminology, gasoline sources, delayed coking
- Question 2: Conversion processes; crude sulphur material balance
- Question 3: The alkylation unit (black-box analysis)
- Question 4: Two-column separation of a light hydrocarbon mixture
- Question 5: Vapour–liquid equilibrium: Raoult's vs Henry's law
December 2016
- Question 1: Multiple choice (crude & product properties)
- Question 2: TBP curve: pseudo-components, IBP/EP, cut points
- Question 3: Fluid catalytic cracking (FCCR) flow sheet
- Question 4: Catalytic reforming flow sheet
- Question 5: Sulphuric-acid alkylation flow sheet
May 2016
- Question 1: Reading the Overall Refinery Block Flow Diagram
- Question 2: The Atmospheric (Crude) Distillation Unit
- Question 3: Characterization of a Crude Oil Cut
- Question 4: The Hydrotreating (Hydrodesulphurization) Process
- Question 5: Identifying and Describing the Coking Unit
December 2015
- Question 1: Polymerization, Crude Distillation and a Refinery-Boiler Combustion Balance
- Question 2: Octane Numbers, Flash Point and a Butadiene Dehydrogenation with Recycle
- Question 3: Characterization Factors, Visbreaking and an Ideal-Gas Tank Pressure
- Question 4: Alkylation Safety, Pour Point and a Distillation Split
- Question 5: Gasoline Properties and an Evaporator with Feed Bypass
- Question 6: Purpose of Refining, Product Specifications and Benzene–Toluene VLE
May 2015
- Question 1: Steam Reforming, Carburetion and an Evaporator with Bypass
- Question 2: Alkylation, Naphtha Cracking and a Coke Furnace
- Question 3: Crude Refining, Product Specifications and SO₂ Absorption
- Question 4: Cloud Point, Hydrogen Production, API Gravity and a Blend Density
- Question 5: Gasoline Properties, Solvent Dewaxing and a Reflux Ratio
- Question 6: Pour Point, Antiknock Additives, Hydrogen Recovery and a Benzene-Hydrogenation Recycle
December 2014
- Question 1: Petroleum-fraction properties, TAN, flash point, and a binary distillation balance
- Question 2: Acid-gas removal, pour point, and percent excess air
- Question 3: Coking processes, API of heavy crude, and an acetylene plant
- Question 4: Gasoline properties, API gravity, and a blended-oil density
- Question 5: Alkylation selection and safety; hydrogen production and recovery
- Question 6: Refinery environmental risks, hydrocracker design, and a sieve-tray balance
May 2014
- Question 1: Steam Reforming, Carburetion and an Evaporator with Bypass
- Question 2: Alkylation, Naphtha Cracking and a Coke-Fired Furnace
- Question 3: Crude Refining, Product Specifications and SO₂ Absorption
- Question 4: Octane Numbers, Flash Point and a Butadiene Recycle Reactor
- Question 5: Characterisation Factors, Visbreaking and an SO₂ Storage Tank
- Question 6: Pour Point, Anti-Knock, Hydrogen Recovery and a Cyclohexane Recycle
December 2013
- Question 1: Hydrogen Production, Reactions and a Benzene-Hydrogenation Recycle
- Question 2: Visbreaking, API Gravity and Flue-Gas Composition
- Question 3: Characterisation of Petroleum Fractions, Flash Point and Mass of Gas in a Tank
- Question 4: Acid-Gas Removal, Isomerisation and Ethane Combustion
- Question 5: Pour Point, Thermal-Cracking Reactions and Ethanol Distillation
- Question 6: Gasoline Properties, Catalyst Deactivation and the Acetylene Plant
Undated paper
- Question 1: Petroleum-refining terminology and API blending
- Question 2: Refinery process units — hydrocracking, alkylation, reflux–stages, desalting
- Question 3: Octane number and octane-improving processes
- Question 4: Thermal (TC) and catalytic (FCC) cracking — process comparison
- Question 5: Two-column distillation-sequence material balance