EB Plant EQUATE Petrochemical Company

Agenda EB Unit Description EB Plant Overview -Basic chemistry -Basic chemistry -Design of EB plant -Design of EB plant - Catalyst - Catalyst -Operating conditions -Operating conditions

EB Unit Description The Ethylbenzene Unit consists of three main sections: 1.Alkylation Reactor Section 2.Transalkylation Reactor Section 3.Distillation Section.

EB Unit Overview

EB Block Flow Diagram

EB simple flow

EB Plant Overview EB Plant Overview -Basic chemistry -Basic chemistry The chemistry of EB reactions is centered on Benzene molecules and Ethylene molecules. The chemistry is fundamentally based on carbon and hydrogen atoms arranged in various combinations. Benzene feed to the process is a six carbon ring compound with three double bonds alternating between the carbons, C6H6 Ethylene feed to the process is a two carbon molecule with double bonds between the carbons, C2H2 C = C

In the EB Process there are two types of reactions: 1- Alkylation Reaction. 2-Transalkylation Reaction. The reaction will produce Ethyl Benzene (EB) in the presence of Zeolite catalyst

Alkylation Reaction Alkylation reaction is the main reaction in EB process where one ethyl group is supplied by Ethylene molecules is being attached to one Benzene ring to produce Ethyl Benzene (EB) C6H6 + C2H4  C8H10 C6H6 + C2H4  C8H10 BZ Ethylene EB The Alkylation reaction is an exothermic reaction, it’s an irreversible reaction and essentially all the ethylene is reacted

Poly Ethyl Benzene (PEB’s) are also produced while producing EB PEB reactions as shown below: C6H5-C2H5 + C2H4  C6H4-(C2H5)2 Ethyl Benzene Ethylene Diethyl Benzene C6H4-(C2H5)2 + C2H4  C6H3-(C2H5)3 Diethyl Benzene Ethylene Triethyl Benzene

C6H3-(C2H5)3 + C2H4  C6H2-(C2H5)4 Triethyl Benzene Ethylene Tetraethyl Benzene Other minor by product are caused by : 1-Ethylene attached at the end of an ethyl group of EB C6H5-C2H5 + C2H4  C6H5-C4H9 Ethyl Benzene Ethylene Butyl Benzene (BB) 2-Benzene reacts with Propylene C6H6 + C3H6  C6H5-C3H7 Benzene Propylene normalpropylbenzene (NPB)

3-Benzene reacts with Propylene C6H6 + C3H6  C6H5-C3H7 Benzene Cumene (CUM) 4-Ethylene reacts with Toluene C6H5-CH3 + C2H4  C6H5-C3H7 Toluene Ethylene Ethyl Toluene Propylene

At the design ratio of Benzene to Ethylene feeds is 2.5 molar basis and seven catalyst beds, the alkylation reaction creates: a.Diethyl Benzene 9.7% b.Triethyl Benzene 0.6% c.Tetraethyl Benzene 0.03% d.Butyl Benzene 0.02%

Transalkylation (TA) Reaction The purpose of TA Reactor is to reacts recycle PEB with Benzene to produce EB. C6H4-(C2H5)2 + C6H6  2C6H5-C2H5 Diethyl Benzene Benzene Ethyl Benzene C6H3-(C2H5)3+ C6H6  C6H4-(C2H5)2 + C6H5-C2H5 Triethyl Benzene Benzene DiethyBenzene EthylBenzene

C6H5-C4H9C6H6  2 C6H5-C2H5 C6H5-C4H9 + C6H6  2 C6H5-C2H5 Butyl Benzene (BB) Benzene Ethyl Benzene

Design of EB Plant

Ethylene specification Page 17 ComponentRequirement Ethylene vol. %, minimum Methane + Ethane 0.02 vol. %, maximum Acetylene 1 vol. ppm, maximum C3 and Heavier 10 vol. ppm, maximum Free Oxygen 2 vol. ppm, maximum Carbon Monoxide 1 vol. ppm, maximum Carbon Dioxide 5 vol. ppm, maximum Hydrogen 2 vol. ppm, maximum Nitrogen (as N2) 100 ppm, maximum Sulfur (as S) 0.1 wt. ppm, maximum Water 5 vol. ppm, maximum Alcohol (as Methanol) 1 vol. ppm, maximum Dienes 5 wt. ppm, maximum Carbonyls (as MEK) 1 vol. ppm, maximum Total Nitrogen Compounds 0.1 wt. ppm, maximum

Benzene specification ComponentRequirement Benzene wt. %, minimum Solidification Point (Anhydrous Basis) 5.40°C, minimum H 2 S and SO wt. ppm, maximum Total Sulfur 1 mg/l, maximum Thiophene 1 wt. ppm, maximum Acidity No free acid Acid Wash Color (Anhydrous Basis) No. 2, maximum Total Chlorides (as Chlorine) 3 wt. ppm, maximum Water 200 wt. ppm, maximum Nitrogen Compounds 1 wt. ppm, maximum Non-Aromatics 1000 wt. ppm, maximum Toluene 500 wt. ppm, maximum Copper Corrosion Shall pass test Bromine Index 10, maximum

EB Specification ComponentRequirement Ethylbenzene wt. % Min. Nonaromatics 500 ppm wt. Max. Benzene 1000 ppm wt. Max. Toluene Benzene + Toluene 1000 ppm wt. Max. Styrene 500 ppm wt. Max. Xylenes 50 ppm wt. Max. Cumene 100 ppm wt. Max. Diethylbenzene 2 ppm wt. Max. Sulfur Total Chlorides (as Chlorine) 2 ppm wt. Max. Color, Pt-Co 5 Max.

Ethylene feed system Control Ethylene feed rate to the Alkylation reactor Control Plant EB Capacity Ensure B/E ratio is acceptable

Benzene feed system Remove catalyst poisons from benzene Take regular samples to track guard bed performance Replace BZ treater4 mol-sieve as needed Use freshest mol-sieve in “downstream” treater

Alkylation system React ethylene with benzene to make Ethylbenzene Control reaction parameters for optimum selectivity and catalyst life B/E ratio at 2.5 (molar) or 7.04 (weight) B/E ratio at 2.5 (molar) or 7.04 (weight) Inlet temperature Inlet temperature Water concentration Water concentration

Alkylator Reactor Reactive Guard Bed AlkylatorIntercooler Ethylene mixers

Reactive Guard Bed Separate vessel containing catalyst Allows replacement while keeping unit in operation Catalyst aging typically only in first bed

Transalkylator React PEB with benzene to make EB No Temperature increase No Temperature increase Preheater to control reactor temperature

Benzene column Recover benzene from reactor product reactor product Furnace reboiler Condenser generates MP steam MP steam 0.5% EB in overhead 700 ppm Bz in bottom product product

EB column Separate EB product from PEB and heavies PEB and heavies Steam reboiler Condenser generates LP steam LP steam 1 ppm DEB in EB product EB product 1 wt% EB in bottom product

PEB column Separate PEB product from heavies from heavies Steam reboiler Condenser preheats condensate (BFW) condensate (BFW) 50 ppm dicyclics in PEB product in PEB product 5 wt% TEB in bottom product

Lights Column Dry fresh benzene (<25 ppm in bottoms) Remove non-aromatics and lights components Heat input by vapour stream from Bz column stream from Bz column Condenser preheats fresh benzene Portion condensed by Cooling Water

Benzene treaters Remove organic N-components from benzene from benzene Mol-sieve operating at elevated temperature (115°C) elevated temperature (115°C) Benzene Treaters contains Benzene Treaters contains two types of molecular sieve, two types of molecular sieve, which has function: 1. As water adsorber  4A molecular sieve 2. As benzene impurities adsorber  13X molecular sieve Volume ratio between water adsorber and benzene impurities adsorber  1 : 3 which has function: 1. As water adsorber  4A molecular sieve 2. As benzene impurities adsorber  13X molecular sieve Volume ratio between water adsorber and benzene impurities adsorber  1 : 3

Benzene Treater contains of two types of molecular sieve, which has function: 1. As water adsorber  4A molecular sieve 2. As benzene impurities adsorber  13X molecular sieve Volume ratio between water adsorber and benzene impurities adsorber  1 : 3 Basic chemistry in the Benzene Treater: C 6 H 6 + B + A  C 6 H 6 + BA Benzene Basic compound Active site on Benzene without Basic compound attached dissolved in Benzene Molecular sieve Basic compound to molecularsieve

EB Plant

Catalyst: Zeolite catalyst. Type : 1- EM – 3300 (Alkylation Reactor) 1- EM – 3300 (Alkylation Reactor) 2- EM – 3700 (TA Reactor) 2- EM – 3700 (TA Reactor)

Catalyst poisons: Nitrogen compounds will deactivate the catalyst by neutralizing acid sites. Maximum 1 ppm in Benzene feed and ppm out of the RGB. Chloride will interact and weaken the catalyst binder. Maximum 1 ppm in Benzene. Chloride will interact and weaken the catalyst binder. Maximum 1 ppm in Benzene. Water, will deactivate the catalyst. Water, will deactivate the catalyst. Metals, will permanently deactivate the catalyst. Metals, will permanently deactivate the catalyst.

Operating Condition

1. BZ to C2 ratio : 7.04 wt/wt or 2.5mol/mol 2. C2 conversion is nearly 100% 3. Effluent Pressure : 34.1 kg/cm2 4. Inlet bed temperature : 195 °C 5. Outlet bed temperature : 257 °C 6. Catalyst : EM-3300 Alkylation Reactor

1.BZ to PEB ratio : 2.0 wt/wt 2.DEB Conversion : 62% 3.Effluent pressure : 31.1 kg/cm2 4.Operating temperature : 200°C 5.Catalyst : EM-3700 TA Reactor :

1.Operating pressure : 1.5 kg/cm2 2.Overhead temperature : 111 °C 3.Bottom temperature : 115 °C 4.Number of tray : 20 trays 5.Water content at bottom : 25 ppm (design) Light Column

BENZENE TREATER 1.Operating pressure : 18.2 kg/cm2 2.Inlet bed temperature : 110 °C 3.Delta pressure : N2 compound at outlet: 30 ppb (0.03 ppm) 5.Adsorbing media : Molecular sieve (4A and 13X)

BENZENE COLUMN 1.Operating pressure : 13.2 kg.cm2 2.Key component temperature : 269 °C (tray 11) 3.Reflux ratio : Overhead temperature : 200 °C 5.Bottom temperature : 280 °C 6.Number of tray : 40 trays 7.BZ content at bottom : less than 700 ppm 8.EB content at overhead : 0.5 % wt

EB COLUMN 1.Operating pressure: 1.1 kg/cm2 2.Key component temperature : 221 °C (tray 5) 3.Overhead temperature : 169 °C 4.Bottom temperature : 231 °C 5.Reflux ratio : Number of tray : 54 trays 7.EB content in the bottom : < 1% wt 8.DEB content in the overhead : < 1 ppm

PEB COLUMN 1.Operating pressure : -0.8 kg/cm2 2.Key component temperature : 176 °C (tray 4) 3.Overhead temperature : 141 °C 4.Bottom temperature : 229 °C 5.Reflux ratio : Number of tray : 20 trays 7.TEB content in bottom : < 5 %wt 8.Heavies content in overhead : < 50 ppm