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FEP and Oleum (Fuming Sulfuric Acid): Chemical Resistance

Fluorinated ethylene propylene

Rating

Concentration20 °C50 °CRemark
10 % SO3A–

Material comparison at 20 °C

Oleum (Fuming Sulfuric Acid): Material comparison at 20 °CFEP: A (highlighted); Aluminium: A; Viton (FPM): A; PTFE: A; SS 304: A; SS 316: A.Aluminium: AFEP: AFEPViton (FPM): APTFE: ASS 304: ASS 316: AEPDM: DHDPE: DLDPE: DNBR: DNylon (PA): DPolycarbonate: DPETG: DPMP: DAcetal (POM): DPP: DPolystyrene: DPolysulfone: DPVC Rigid: DPVC Flexible: DPVDF: DECTFE/ETFE: –SAN: –Silicone: –
A very good resistanceB good resistanceC limited resistanceD not resistantno data
Each bar is one material. Taller bars indicate better resistance. The highlighted bar is the current material.

Resistance overview

FEP shows very good resistance (A) to Oleum (Fuming Sulfuric Acid) at 10 % SO3 at 20 °C, meaning the material remains essentially unaffected by this chemical under standard laboratory test conditions. The rating remains stable between 20 °C and 50 °C, which means this material can also handle moderately elevated process temperatures without additional risk.

Application context

Oleum (Fuming Sulfuric Acid) is commonly encountered in chemical processing and metal finishing. FEP (Fluorinated ethylene propylene) is a fluoropolymer typically used for seals, gaskets, valve seats and lined equipment. Because Oleum (Fuming Sulfuric Acid) is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.

Practical recommendation

FEP can be used with confidence for Oleum (Fuming Sulfuric Acid) containment and handling. The A rating indicates that the material shows no significant change in weight, dimensions, or mechanical properties after prolonged contact under test conditions. This holds true at both 20 °C and 50 °C, giving a good safety margin for typical process environments.

Did you know?

Chemical resistance testing according to DIN and ISO standards typically evaluates weight change, dimensional change, and retention of tensile strength after immersion.

Materials rated A or B at 20 °C

Based on the row for 10 % SO3, 20 °C.

Fluoropolymers
PTFE A
Elastomers
Viton (FPM) A
Metals
SS 316 A, SS 304 A, Aluminium A

About FEP

FEP has nearly the chemical resistance of PTFE and can be melt-processed. Its service temperature, about 200 °C, is lower than that of PTFE.

Rating scale

A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.

About this data

The ratings come from the chemical resistance list published by Bürkle GmbH, which compiled them from raw-material manufacturers’ data. They describe laboratory tests on the raw material at 20 °C and 50 °C.

A finished part also sees pressure, mechanical stress, welds and mixtures that a laboratory test does not. Treat the rating as a first filter and test under your own conditions before relying on it.