The perils and merits of ‘fake flake’ graphite

By Jon Stibbs, Sybil Pan
Published: Tuesday, 19 January 2021

More instances of “fake flake” graphite being sold as genuine material have been reported, especially as large flake sizes. Fastmarkets spoke with market sources to gauge this material’s effect on the market and its uses when sold correctly.

So-called "fake flake" is the name given to man-made graphite flake that has been falsely sold as natural flake or has been blended into genuine flake. In these circumstances, buyers are misled into purchasing material that will not perform to the same standard as natural flake.

While it lacks the durability of genuine natural flake, fake flake does have a useful role in the market when sold fairly and openly as a lower-cost alternative to natural flake. "The properties are different to those of pristine flakes and for many applications they can’t be used – like for expandable graphite," one producer source said.

In these cases, it goes under several names, such as "man-made", "pressed" or even "synthetic" flake in China. The latter needs to be clearly differentiated from the more expensive and high-quality synthetic anode graphite that more commonly carries the same name.

Most fake flake is in larger flake sizes, such as graphite flake, 94%, +80 mesh, because high profits can be achieved with this material since it is higher priced than smaller flake sizes.

Fastmarkets’ price assessment for graphite flake 94% C, +80 mesh, fob China, was $920 per tonne on November 12, 2020, up by $10 from $910 per tonne on November 5. But the fake flake equivalent sold for around $400-700 per tonne on an fob basis. When it is sold honestly as man-made or pressed flake, it is priced toward the top end of that range, according to sources.

How it is made

"Fake graphite is still graphite, however it is small pieces of graphite pressed together, so they appear as large flake – so-called fake flakes," the producer source said. At its simplest, it is made using the waste from the processing of flake into spherical graphite fines, which is then held together using a binder.

The average yield of spherical graphite processes is 30-50% of its feedstock volume. That is, 50-70% of the feedstock graphite is waste. There are about 120,000 tonnes of waste from spherical graphite production, which could be processed into flake graphite and used in the refractories sector, a trader in China said. So there is a lot of this material available.

"This is typically pushed through an extruder and then dried," a second producer source said. The process has developed over time while the market in China for large flake sizes tightened. "Initially, they would only do wet compression [water only], then when people caught on they began using water-soluble binders. They eventually moved onto more sophisticated binders," a graphite trader said.

Since then, variations and improvements have emerged, according to a second trader source. "While [Chinese producers] started to press inferior flake into larger flake [in the 1980s], we have now a wide range of 'fake’ flake materials," a second graphite trader said. "We have detected at least three precursor materials."

Increasingly prevalent

Demand for +894 material for expandable graphite has risen, while supply in China has tightened, resulting in increased prevalence of fake flake in the market in recent months. "Most of the larger flake graphite [in China] will be processed into expandable graphite or other value-added product locally instead of selling the raw material directly," a third graphite trader told Fastmarkets.

On the one hand, the material has been – and continues to be – sold to mislead buyers. At the same time, a market has also emerged for buyers who have knowingly acquired this lower-cost material.

"The market took a negative view of the deceptive practice, but as economics show, the buyers liked the lower pricing despite the lower performance of the pressed materials," the first trader said. The crucial element is whether the material is sold as something it is not, or after the buyer has been fully informed of its components and its uses.

"Fast forward to [the present day] where pressed flake is an accepted and marketable material, with an entire segment built around the production of goods… However, the presence of this material when it has been falsely sold has a strong negative effect on buyers and can have a strongly detrimental effect on trust when it has been sold fraudulently," the first trader said.

"Maybe I should not buy from Chinese producers any more but I am not sure if I can access enough material from Africa to meet my needs," one market participant said, who had been sold fake flake under the guise of pure natural flake.

Why it is used

"Sometimes buyers agree to have some fake flake graphite mixed in as long as it will not affect the refractory characteristics of the material. We have some customers in the domestic market who would like to have gradual tests of the mixture so as to reduce their cost," a fourth trader said.

The crucial element is the basis on which the material is sold, whether the buyer has informed the seller of the material involved. When sold fairly, it has attributes sought by buyers in addition to the lower cost.

"Our company policy is to provide full transparency on those materials, as some of them surprisingly give better results in the customer process than the 'real’ flake. Because of that, we refer to those products as man-made flake and do not take advantage of windfall margins by cheating the customers," the second trader said.

In fact, it has developed a respected position in the market among some buyers, sources said. "In a world of carbon footprint issues, recycling and environmental awareness, this is not a product to be damned. Of course it has nothing to do with mined natural graphite," the second trader said. "There is a market for it like minced meat burgers made from tofu. If you use it to cheat a meat lover, this is certainly unethical, but it is pleasing vegan/green target groups."

So it can have a role in the foundry and the refractories sector under certain circumstances, according to sources.

"This can be enough of an incentive to use it until there is an issue," the third producer source said. "The performance may pass through undetected or undifferentiated against other material quality issues from other inputs."

Graphite flake 94% C, +80 mesh, fob China, $/tonne

How to identify it

While this material has a genuine role in parts of the market, it also continues to be falsely sold as more expensive pure natural graphite. To avoid being deceived, buyers must be able to identify it. There are several different processes employed while buyers seek to avoid being sold false material.

"Detection came in the way of simple attrition for the early versions, then came the simple test of water 'solubility’ which removed the binder, and now the process is quite perfected, making it difficult to determine. Aside from the difference in visual morphology of the flake, it is difficult to detect, except for one test surface area," the first trader said. "The fine precursor material will have a significantly higher surface area than that of pristine +80 or +50 mesh flake."

It can be difficult to detect the fake material that has been processed with the waste from spherical graphite.

"I heard that, for the fake larger flake graphite, it could be tested with an 80-mesh filter, fake flake graphite might have a lesser share of the 80-mesh because of the finer feature of the feedstock," the third trader said.

Testing is not always successful, so fake flake could be successfully and inappropriately used until there is a problem, market sources said.

"For the quality control [QC] process, this material can be differentiated with a small acid test [using sulfuric acid] which disintegrates the binder and leaves you with the fine graphite residue. This material is designed to bypass the QC testing for particle size distribution [sieve screening] and carbon content QC, so it’s often not picked up until there is an issue," the third producer source said.

When the material has been sold with the intent to mislead the buyer, sellers take precautions in an effort to carry through the deception. "Because the material is usually sold as 'genuine’ flake, pre-shipment samples sent would typically be real +80 mesh, only switching to the man-made product for delivery," the third producer added.

Suspicions should be raised for the potential sale of material from new contacts offering spot material at an unusually good price. Reportedly, sales are mostly from intermediate processors and traders rather than graphite flake producers.

While there are relatively few producers, the Chinese graphite market has many small-sized traders and processors so it can be difficult to identify who might sell material dishonestly.

"We spend a great deal of time vetting our suppliers," the second trader said, "and we tend to shy away from low-cost 'spot buys’ from traders, preferring to purchase, typically, directly from mine operators that we know and have vetted."