Residual Aromatic Extract (RAE) Definition

Residual Aromatic Extract (RAE) is a high viscosity aromatic process oil made from a residual oil fraction. It is used as extender oils in rubber and tyres. The Polycyclic Aromatic Hydrocarbon (PAH) content is less than 1ppm and total PAH less than 10ppm.

RAE Applications

used as carrier oil, plasticizer, diluents & filling agent that remain in the final product contributing to both ease of processing and improved product performance in rubber industry.

RAE CHARACTERISTICS

1. Good abrasion resistance
2. Good low temperature flexibility
3. Low amounts of waste tyres in the process
4. Good resistance to reversion
5. According to with international standards (EU 2005/69/EC)
6. Save fuel and energy consumption
7. Extend tyres life time
8. Good Solubility Properties.
9. Improving processing ability of rubber in milling and mixing.

Physico-Chemical Data

Aromatic extracts were assessed for water solubility using the estimation program WSKOW V1.40, which is a subroutine in the EPI-Suite V3.10 (EPA 2000) computer program. Isomeric structures of 15 carbon atoms were selected since these would be expected to have the highest solubility values for the different molecular structures in aromatic extracts. Structures of 50 carbon atoms were included to demonstrate the decrease in water solubility with increasing size of the hydrocarbon molecule. These carbon numbers essentially span the general definition given for the constituents in aromatic extracts. Values in the following table that were cited in the WSKOW experimental database are denoted by “*”. Solubility Estimate (mg/L) C-Number Structure C15 C50 iso-paraffin 3.3×10-3 1×10-21 1 ring naphthene 0.004 1×10-21 2 ring naphthene 0.03 1×10-20 3 ring naphthene 0.18 1×10-19 1 ring aromatic 0.04 1×10-19 2 ring aromatic 0.63 1×10-18 3 ring aromatic 0.27* 1×10-19 4 ring aromatic 0.14* 1×10-18 Note: C15 structures modeled were isopentadecane, nonylcyclohexane, pentylbicyclohexane, methyltricyclohexane, n-nonylbenzene, 2-butylnaphthalene, and 5- methylphenanthrene. Pyrene was the representative 4 ring aromatic and has 16 carbon atoms. C50 structures were similar structures except for the additional alkyl groups. Water solubility of distillate aromatic extracts was reported in CONCAWE (1992) as ranging from 1.4 to 5.8 mg/L and as “negligible” for residual aromatic extracts. The references for those values were not cited in the CONCAWE dossier and no substantiation of the values could be located. Therefore those data were not considered reliable although they were reported in a public dossier.