Natural Graphite - hydrothermal vs sedimentary
posted on
Oct 10, 2014 05:58PM
Hydrothermal Graphite Deposit Ammenable for Commercial Graphene Applications
The debate is still raging on about hydrothermal vs sedimentary (often referred to as flake graphite). As we all know the process Mother Nature used for hydrothermal is different, and I will attempt to explain in simple language (no geo, but has enough home schooling to follow scientific processes)
- Hydrothermal: from Earth's magma coming up and reacting with the surrounding enviroment, rocks, etc...
- Sedimentary: organic material coming down from above and settling at the bottom of oceans, and Mother Nature would bake it under great pressure. The resulting graphite would also be subject to movement of the Earth's crust due to geological events to arrive at its present location, close enough to the surface for us to discover.
Let's just say that the hydrothermal process would produce graphite with higher purity than sedimentary one, hence the purification process required to bring sedimentary graphite to the same purity level with hydrothermal is more involved. But, as long as the impurity can be separated with reasonable cost for a desirable application then sedimentary graphite would be an economically option. Perhaps, it would fetch lower prices than hydrothermal graphite. However, if they have willing buyers to pay high enough price to make some decent profit then sedimentary graphite should be a profitable commodity.
In order to get into the high-end battery for EVs, companies with sedimentary graphite have demonstrated that high enough purity can be achieved and large flake graphite could be rolled up to form spherical graphite (SPG), also called potato graphite, which can be carbon-coated for making high-end batteries. The price would range from $3.5k to ~10k for non-coated and coated respectively. Currently, most of the carbon coating is done in Japan.
What I don't quite understand is that we are still hung up about hydrothermal versus sedimentary graphite (ofter called flakers, which has a "not so good" connotation ). Sedimentary graphite has flakes ranging from fine to large/jumbo. What about hydrothermal graphite...it is not "flake graphite"? In other words, it does not have flakes?
I am not sure what I have misread the information, but the Dr. Andrew Conly of Lakehead Unviversity, consultant to ZEN, has indicated the flake size of ZEN hydrothermal graphite ranging from fine to large, and this was described in ZEN NR of
27 February 2012
http://www.zenyatta.ca/article/press-release-185.asp
In addition, there are photographs of Albany graphite under an electron microscope (ZEN website). They looks like flakes which are quite similar to those of "flake" graphite (Google, flake graphite under electron microscope...check out the one from Ashbury).
From what I saw, Albany graphite also has flakes, but it came from a different origin. It's from inside Mother Earth, while the sedimenatry flakes came from "outside" (artificial insemination?) to be baked under extreme pressures.
In my opinion, there is no point pitching hydrothermal against sedimentary. They are both natural and flake graphite. It would be much more productive to join force (or leave each other alone) to try to compete with synthetic graphite (rather than fighting among sibblings).
goldhunter