PTT invests in petrochemical and refining business through its subsidiaries.  PTT has appointed Petrochemicals and Refining Business Unit to manage,
set up business strategy, and create synergy among all the subsidiaries.

PTT Group operates a total integrated petrochemical business through its 8 subsidiaries, starting from raw materials straight down to plastic resins. The whole chain includes upstream of olefins and aromatics, the intermediates and downstream of polymers and specialty chemicals. PTT Group is not only the biggest petrochemical producer in Thailand, but also one of the top companies in the region.

Petrochemical business of PTT Group also includes polymer marketing, both domestic and international sales, logistic services, maintenance & engineering services  and utilities. 

1. PTT Chemical Public Company Limited (PTTCH)

- Produces and sells a complete range of olefins and related downstream products including High Density Polyethylene (HDPE)   
- Produces and sells electricity, water, steam and storage & transportation services such as port and depot to other downstream petrochemical manufacturers

2. IRPC Public Company Limited (IRPC)

Produces and sells 2 main product groups
     - Petrochemical products : Olefins, Aromatics, and Plastic resins which are High Density Polyethylene (HDPE), Polypropylene (PP), Acrylonitrile Butadiene Styrene (ABS/SAN) Expandable Polystyrene (EPS) and Polystyrene (PS)
     - Petroleum products : Fuel, lubricant, and asphalt with refining capacity of 215,000 barrels/day.

3. HMC Polymers Company Limited (HMC)

- Produces and sells Polypropylene (PP)

4. PTT Phenol Company Limited (PPCL)

- Produces and sells Phenol and Acetone  (start up by 2008)

5. PTT Asahi Chemical Company Limited(PTTAC)

- Produces and sells Acrylonitrile (AN) and Methylmetacrylate (MMA)  (start up by 2010)

6. PTT Polymer Logistics Company Limited (PTTPL)

- Provides full logistic services both domestic and export including packaging, storage, warehouse management and transportation.

7. PTT Polymer Marketing Company Limited (PTTPM)

- Sales and marketing of all polymers produced by PTT Group

8. Alliance Plant Service Company Limited (APS)

- Provides maintenance, design and engineering, construction, start-up, materials procurement and management,  production management and training services to PTT Group and others industries in Thailand and Asia

PTT invests in refining business through its 4 subsidiaries with total refining capacity of PTT Group is 401,754 barrel per day which is equivalent to 34.57% of the total refining capacity in Thailand.  PTT has supplied crude which is procured from both domestic and international sources for all those refineries.  The domestic crude is exclusively gone to Thai Oil and Bangchak.  Besides supplying crude, PTT has offtaked petroleum products from all 4 refineries and distributed through PTT oil wholesale and retail marketing channels.  In general, volume offtake is in term of PTT shareholding ratio.

1. Thail Oil Public Company Limited (TOP)

Refining capacity of 275,000 barrels per day
Main products:

• Light products : LPG, Gasoline, Mixed Xylene, Reformate and Isomerate
• Middle Distillate : Jet Fuel and Diesel
• Heavy products : Fuel Oil, Long Residue and Bitumen

2. PTT Aromatics and Refining Public Company Limited (PTTAR)

PTTAR arose from the amalgamation of the Aromatics (Thailand) Public Company Limited (ATC) and Rayong Refinery Public Company Limited (RRC) to conduct an integrated aromatics refinery.

• Refining Business: Produces and sells petroleum products with a capacity of 145,000 barrels per day with a condensate splitter to produce reformate at a capacity of 70,000 barrels per day.
• Aromatics Business : Produces and sells aromatics and related intermediate products with a capacity of 1,189,000 tons per year.

3. Star Petroleum Refining Company Limited (SPRC)

Refining capacity of 150,000 barrels per day
Main products:

• Light products : LPG, Gasoline, Light Naphtha, Reformate and Propylene
• Middle Distillate : Jet Fuel and Diesel
• Heavy product : Fuel Oil

4. Bangchak Petroleum public Company Limited (BCP)

Refining capacity of 120,000 barrel per day
Main products:

• Light products : LPG and Gasoline
• Middle Distillate : Diesel and Jet Fuel
• Heavy product : Fuel Oil