The document discusses the myth that aromatics content significantly impacts evaporation rates in metallurgical grade kerosenes. While aromatics like benzene, toluene, and xylene are commonly associated with higher evaporation, the document finds evaporation is more dependent on initial boiling point. Analysis of Solvex, a metallurgical kerosene, finds its high initial boiling point of 205°C rules out significant benzene, toluene, and xylene content, despite these compounds being aromatic like the copper-oxime extractants. The document concludes aromatics have marginal influence on evaporation rates compared to initial boiling temperature.

1. Guillermo Stephens, David Belmar, Sergio Valladares
The Mith of Aromatics Contents in Metallurgical
Grade Kerosenes

2. Frequently asked question by the potential users
of metallurgical kerosenes:
• What is the % of aromatics in the solvent?

3. Commonly associated concepts to the presence
of aromatics in metallurgical kerosenes
• High evaporation rate
• Presence of harmful compounds, like Benzene, Toluene, and
Xylene

4. Requisites of a Metallurgical Grade
Kerosene
• High Flash Point
• Insoluble in water
• Low viscosity
• Relatively low density
• Capable of maitaining the copper – oxime complex in solution
• Fast phase disengagement
• Available at relatively low cost

5. Paradox
Benzene
The hydroxyoximes molecules are aromatic compounds

6. Benefits of the metallurgical solvents which
contain aromatics
• Greater capacity to maintain the copper – oxime complex in
solution at high reagent concentrations.
• Protects the extractant from Nitration reaction.

7. Evaporation rate v/s aromatics contents
0.000
0.100
0.200
0.300
0.400
0.500
0.600
0.700
1 2 3 4 5 6 7 8 9 10 11 12 13
EvaporationKg/day*m2
Days
Sample A
Sample B
Sample C
Sample D
Sample E

8. Evaporation rate v/s Initial Boiling Point
Days

9. Comparative evaporation rates of available solvents
Days

10. SX Diluentsmmmmmmmmmmmmmmmm
Composition:
% by weight
• Paraffines and Isoparaffines
• Cycloparaffines, Naphthenics 75 - 99.5
• Aromatics 0.5 - 25
. Distillation Range 200°C – 260°C
. Flash Point > 75°C
. Density at 20 °C 0.800 – 0.820 gr/cc

11. Hydrocarbon Compound.
ALKANES ALKENES ALKINES NAPHTENES
(Cycloalkanes)
ALIPHATICS AROMATICS
HYDROCARBONS
C
x
H
y
• Products obtained from oil refining

12. Benzene Toluene Xylene ( o-m-p)
C6H6 C7H8 C8H10
BTX Aromatics
Aromatic Compounds
CH3

13. Solvex Specification

14. 0°C 50°C 150°C100°C 200°C 300°C250°C 350°C 450°C400°C 500+°C
LPG FUEL OILKEROSENE
NAFTA DIESEL
BITUMEN
150°C 205°C 260°C 300°C
(572°F)
SOLVEX M
BTX
Oil Refining Fractions
70°
C

15. Solvex Gas Chromatograph
BTX

16. Conclusions
• Aromatic compounds have a marginal influence on the
evaporation rate of a metallurgical kerosene.
• The evaporation rate is strongly dependent on the Initial
Boiling Temperature at which the process starts.
• The presence of the BTX compounds in Solvex is ruled
out due to its high IBP (205°C).

17. GRACIAS
THANK YOU