• To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Electrowinning, Smelting or Refining.
  • OR Select a Topic that Interests you.
  • Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
    Using Add Reply allows you to Attach Images or PDF files and provide a more complete input.
  • Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.

Effect of Industrial fuel tracer on diluent performance (4 replies)

Helena Russell
10 months ago
Helena Russell 10 months ago

Does anyone have any experience of the addition of a fuel industry tracer to a diluent - particularly on the physical performance of copper SX systems? The tracer, going under the trade name of Authentix A1, is added only to change the colour of the diluent.

Dizzy Flores
10 months ago
Dizzy Flores 10 months ago

In the past a trace chemical was added to diluent sold to SX plants in Australia to enable the excise people to check that the diluents, which was excise free, was not sold on to other users. I recall that it had some effect on phase separation. If you run a BASF QC test then you should be able to determine if the colour additive has any effect.

Bill Fraser
10 months ago
Bill Fraser 10 months ago

When I worked for Cerro Colorado SX plant, we had an increase of phase separation time in our oxide kerosene organic blend, because the haulers leaked a little fraction of oil in the ore of the heap leaching. The PLS ponds had a typical thin iriscedescent film in the corner.

I do not remember a color changes in the organic, but the phase separation time in the mixer settler extraction stages was over four minuteshigh because we operated with 12 to 13 % of extractant, and organic inventory was only 4 years old.

We decided to treat the organic adding activated clays in a short time contact 5 minutes and then filter, after a laboratory test suggested.

Bill Rico
10 months ago
Bill Rico 10 months ago

I have messed around with a variety of tracers and dyes before, but never the Authentix A1 that you mention. Generally, I had to undertake a series of my own bench-scale tests until I found a satisfactory colorant. Problems generally occurred when an alcohol or an extractant/modifier with reasonable solvating power was present in the SX system. It usually resulted in poor PDTs and also gradual movement of the colour between phases. Also, when surfactants/poisons were present, even in the smallest quantities, the addition of a colouring always resulted in dramatically worse PDTs in comparison to surfactant alone.

I guess it will come down to the type of molecule that Authentix A1 is.

Marshal Meru
10 months ago
Marshal Meru 10 months ago

The effect of Authentix A1 was the basis of a great deal of SX compatibility testing in the Shell lab back in 2008 when the South African government insisted on its addition to all hydrocarbons locally produced that could possibly be used as a fuel, including diluents.

The N-methyl pyrrolidone is certainly the molecule of concern here and has some mixed blessings. Firstly, it is aqueous soluble but only mildly soluble in the hydrocarbon and will therefore be fairly quickly lost to the raffinate. However, being very surface active and those nasty lone pairs of electrons are always a concern before it is flushed out of the system.

In summary, at the correct dose rate of 20ppm, there is little or no effect on the CuSX process and this has been backed up by the past 5 years of the addition of the tracer to diluents on the African continent. At the correct dose rate of 20ppm :-

• PDT’s were identical to unmarked diluent

• Kinetics and Org/Aq Isotherm ratios were slightly depressed

• Cu/Fe selectivity actually improved quite dramatically

Overdosing concentrations of 40, 60 & 80ppm were also investigated with progressive worsening of all parameters except for the Cu/Fe selectivity which continued to improve. PDT’s doubled and the Org/Aq Isotherm ratios dropped by over 20% in the worst case. Although overdosing is not expected, even these worst case scenarios are not expected to cause any long term problems to the organic.

Up until the mid 2000’s, the Australian government insisted on a tracer to be added to all hydrocarbons. That tracer, Mort race MP was based on oleic acid which has detrimental effects on both PDT’s and selectivity, consequently an exemption from dosing diluents into the SX industry was lobbied for and eventually granted. This dosing ceased around 2005 and is no longer an issue (except for the bean-counters who need to claim the excise back that is now paid up front!).

Please join and login to participate and leave a comment.