Overview

Recovered. Purified. Delivered.

Maleic anhydride (MA) is a key reactive intermediate produced as a coproduct during IGPL's phthalic anhydride manufacturing process. The same vapour-phase oxidation of o-xylene that produces PA generates MA as a byproduct — IGPL recovers and purifies this stream through four dedicated MA recovery units at the Taloja campus.

Unlike MA produced as a primary product by dedicated maleic processes (butane oxidation), IGPL's MA is integrated with the PA output stream. This means the economics and supply discipline of IGPL's MA are closely linked to PA production — offering customers a stable, integrated source tied to one of India's largest continuous chemical operations.

MA from IGPL is supplied in solid flake form or as a molten liquid, meeting the purity standards required for UPR, agricultural chemical synthesis, and food-grade fumaric acid conversion.

At a Glance

Purity ≥99.5%

Recovery Units 4

Source PA coproduct

Form Flakes / Molten

CAS

108-31-6

Formula

C₄H₂O₃

Mol. Wt.

98.06

Applications

Where Maleic Anhydride Is Used

Unsaturated Polyester Resins (UPR)

Largest single application. MA reacts with glycols to form UPR for fibreglass composites, pipes, tanks, boats, and automotive panels.

Fumaric Acid

Isomerisation of maleic acid to fumaric acid, used in food additives, beverages, and polymer synthesis.

Malic Acid

Hydration to malic acid for food and pharmaceutical applications including flavour enhancement and acidity regulation.

Agrochemicals

Malathion, maleic hydrazide, and related herbicide and insecticide intermediates in crop protection chemistry.

Lubricant Additives

Copolymers with alkenes for viscosity index improvers and dispersants used in engine oils and industrial lubricants.

Specialty Copolymers

Copolymers with styrene, vinyl acetate, and ethylene for specialty coating and adhesive applications.

Production

Integrated Recovery from PA Process

During the vapour-phase oxidation of o-xylene to phthalic anhydride, the reaction selectivity produces a small fraction of maleic anhydride in the process gas stream. Rather than combusting or venting this stream, IGPL operates four MA recovery units that extract, condense, and purify this material to commercial-grade specification.

This integration has two advantages: it improves the overall carbon utilisation of the PA process (reducing waste), and it provides a secondary revenue stream from the same raw material and energy input. The recovery units at Taloja have been refined over multiple PA plant expansions since the 1990s.

Recovery Process Flow

O-Xylene Oxidation

PA + MA in process gas

MA Recovery Unit

Condensation & separation

MA ≥99.5%

Flakes or molten

Specifications

Technical Specifications

Parameter	Specification	Test Method
Purity (MA content)	≥ 99.5%	GC
Colour (APHA, molten)	≤ 10	APHA
Acid value	1,142–1,148 mg KOH/g	Titration
Moisture	≤ 0.1%	Karl Fischer
Iron content	≤ 5 ppm	ICP-OES
Appearance	White crystalline flakes	Visual
Melting point	52–54 °C	DSC

Specifications subject to change. Always request current TDS from the commercial team prior to formulation.

IGPL provides batch-specific Certificates of Analysis (CoA) with every shipment. Maleic anhydride purity and melt colour are tested per batch. For supplier qualification documentation, contact our technical team.

Why IGPL

Why Source MA from IGPL

Integrated Supply

MA produced and recovered on the same campus as PA. No separate feedstock risk or dedicated plant downtime.

Consistent Quality

Four dedicated MA recovery units, continuous QC monitoring, APHA colour controlled within customer specs.

JNPT Proximity

Taloja location, 50 km from JNPT, enables export logistics and compressed lead times for both domestic and overseas customers.

30+ Years

IGPL has operated MA recovery since the earliest PA plants. Process optimisation across decades delivers yield and quality discipline.

FAQ

Frequently Asked Questions

IGPL supplies maleic anhydride as solid white crystalline flakes in bulk bags (500 kg) or drums. Molten delivery by tanker is available for large-volume customers with suitable storage facilities at their plant.

Standard commercial grade is ≥99.5% purity. This meets the requirements of UPR manufacturers, agrochemical intermediates, and food-grade conversion processes (fumaric/malic acid).

IGPL MA meets the purity and trace impurity specifications typically required for fumaric acid synthesis. Customers producing food-grade fumaric acid should request the detailed TDS and confirm against their specific process requirements.

Maleic anhydride should be stored in a cool, dry, well-ventilated area away from sources of heat and moisture. Shelf life for solid flakes is typically 12 months under appropriate conditions. MA is hygroscopic and must be kept sealed.

MA is a coproduct recovered from the PA process. Production volumes are therefore proportional to PA production throughput. Customers should contact the commercial team to discuss volume availability for specific planning periods.

Maleic Anhydride