Diabetes Strips
Challenge
Recoup and recycle gold from rejected diabetes circuit strips manufactured by a major medical manufacturer
Deposition
Gold
Substrate
Kapton Polymer, Mylar
Results
An inexpensive and fast solution to the problem was developed that fulfilled the manufacturer‘s requirements and provided a process where there was literally no gold loss, the plastic and the glue was stripped off within a couple of minutes, and the gold was smelted right afterwards.
One of the largest producers of medical supplies was looking for a gold recycling solution to try to recoup the gold from their production scrap of diabetes strips.
The production scrap was the gold circuit which is encapsulated/laminated in a polymer called Kapton, glued by a product called Mylar.
A major refiner asked us, to come up with a process to do this.
Most refiners usually incinerate (burn the plastic film down) the plastic and then extract the gold particles from the resulting ash.
Since the incineration is (1) carried out at high temperatures, (2) oxygen is used, and most importantly (3) thin layers of gold are involved, the FIRST LOSS of GOLD at the refineries is due to this step.
This is mainly due to the fact that the thin layers of gold behave quite differently than chunks of gold during burning.
The next step is to dissolve the gold (extraction) in liquid chemicals (aqua regia for instance), which leaves the ash behind (undissolved), please note this is the SECOND LOSS of GOLD. Especially taking into account that the total surface of the ash is huge and some gold is obviously going to stay undissolved and further the amount of gold left behind on the ash is difficult to control.
Having all of that in mind, we knew that we were ideally aiming for a process technology that would:
(1) eliminate the burning (incineration), i.e. avoid the first loss of gold;
(2) potentially skip the extraction of the gold from ash, i.e. avoid the second loss of gold;
(3) be fast and inexpensive;
(4) be robust and simple enough to scale-up in potentially remote locations by an done by staff who did not need very specialized training.
Our approach was to develop a process to remove both the Kapton plastic and Mylar glue by chemicals, in order to fulfill requirements 1 and 2, above.
After some unsuccessful experiments, we were able to come up with a really inexpensive and fast solution, which also fulfilled the remaining 3 and 4 requirements above.
By fulfilling all four requirements, there is (i) literally no gold loss, (ii) the plastic and the glue are stripped within couple of minutes, and (iii) the gold can be smelted right afterwards.
The technology was demonstrated to our client (refiner), and we are currently in discussions to license the technology to them so that they can scale it up for production use.