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Purified Terphthalic Acid

Reliance Industries Limited (RIL), India's largest private sector company produces PTA at it's petrochemical complexes.

With 2,050 KTA capacity, RIL is 8th largest producer of PTA in the world. RIL has been able to achieve this position in less than 10 years. RIL's world class manufacturing technology and strategic interest in this business are the main reasons for this growth.

PTA was first introduced in 1965 as an alternative feedstock to Dimethyl Terephthalate (DMT) for the production of Polyester. By end of 1999, almost 85% of total world production was based on PTA and this continues to grow.

Purified Terephthalic Acid (PTA) is the preferred raw material for Polyester. Polyester was first introduced in 1951 and today it finds applications in all walks of life. Clothing, furniture, upholstery, containers, films are some of the major applications of Polyester.

ISO Accreditation

RIL believes in installing and maintaining it's manufacturing sites at world class level. Both the manufacturing complexes have received ISO 9002 accreditation. RIL's Hazira complex has received ISO 14000 accreditation in 1999 and also has been awarded 5 star rating from British Safety Council for consecutive 3 years.

DuPont Technology

The technology for PTA has been licensed from DuPont (earlier ICI). This world class technology enables production of the highest quality. The level of automation installed in Reliance PTA plants ensures total quality control. Our production sites have already installed Advanced Process Control (APC) and Computer Integrated Manufacturing (CIM), which keep a constant watch on product quality and take on-line corrective actions.

APPLICATIONS:

1. Polyester

PTA is a basic raw material for Polyester. PTA reacts with MEG to produce polyester.

A) Textiles

PTA derivative, Polyester, is the largest synthetic fibre used in textiles. With more than 18 million tons of fibre production in a year, Polyester is second only to Cotton 20 million tons). With cotton availability being restricted, the growing demand of fibres is largely met by Polyesters. Polyester Filament Yarn can be directly used for textiles, while Polyester Staple Fibre is blended with other fibres before being drawn into a yarn.

B) Packaging

Polyethylene Terephthalate (PET) Film, sheet and moulded containers for food packaging continue to grow in popularity. Lightweight soft drink containers based on PTA are crystal clear and shatterproof. Boil-in-bag pouches use polyester films, while retortable and microwave packages use coextruded films and containers. In addition, blister packaging for fresh and prepared food products is often based on PTA. The success of PET recycling efforts makes PTA the raw material of choice for new food packaging ideas.

C) Furnishings

Staple Fibre made from Polyester is also used in furniture applications like cushions, upholstery etc. Continuous development in this fibre segment has opened a very good opportunity in this segment.

D) Consumer Goods

Apart from uses in Textiles, Furnishings as detailed above, PET is also used in films for audio and video recording tapes. Sun-Control films are also based on PET. PET has also become the primary container resin for carbonated soft drink bottles and other applications.

2. Coatings

PTA is used in the polyester component of environmentally compliant coating resins, including water soluble and powder systems. Their inclusion formulation helps determine the weatherability, corrosion resistance, flexibility and impact resistance, as well as other performance characteristics of the coating in either household or industrial use.

3. Resins

PTA also finds applications in unsaturated polyester resins which are used as engineering plastics.
The list of applications does not end here. Continued development in all above segments is based on Polyester resin for which PTA is the natural raw material.


SPECIFICATION:

(Finished Product)

Sr.No. Parameters Method No Unit Specification Limits
1 Appearance PTAH/QCD/3501 -- White free flowing Crystalline Powder free from visual contamination
2 Powder Colour ‘Y’ PTAH/QCD/3502 -- 11.0 max.
3 4-Carboxy Benzaldehyde PTAH/QCD/3503 wt. ppm 20 max.
4 p-Toluic Acid PTAH/QCD/3504 wt. ppm 150 max.
5 Water PTAH/QCD/3505 w/w % 0.15 max.
6 Millipore PTAH/QCD/3506 -- 0.95 min.
7 Colour in 2M KOH PTAH/QCD/3507 HAZEN 10 max.
8 b* - Colour PTAH/QCD/3508 -- 0.80 + 0.40
9 Ash PTAH/QCD/3509 wt. ppm 8 max.
10 Total Metal content PTAH/QCD/3510 &12 wt. ppm 6 max.
11 Individual metals-Cobalt Manganese Iron Chromium PTAH/QCD/3510 & 3512 wt. ppm wt. ppm wt. ppm wt. ppm
  1. max.
1.0 max. 0.5 max. 1.0 max.
12 Calcium Magnesium Sodium Copper Nickel PTAH/QCD/3510 & 3512 wt. ppm wt. ppm wt. ppm wt. ppm wt. ppm 1.0 max 1.0 max. 1.0 max.
  1. max.
1.0 max.
13 Acid number PTAH/QCD/3513 mgKOH/gm KOH/gm 675 + 2
14 Benzoic Acid PTAH/QCD/3504 wt. ppm 30 max.
15 MPS PTAH/QCD/3508 Micron 95 + 15
    PTAH/QCD/3515 Micron 105 + 15
16 UV Transmission @ 340 PTAH/QCD/3514 % 91.0 min

Notes :

  1. The metals listed in Sl. No. 12 are analysed only if the ash content exceeds 6 ppm.

  2. Routinely MPS will be analysed by Laser technique, however in case of non-availability of instrument, same can be analysed by mechanical sieve shaker.