With our mass-produced butane lighters and matches made in the billions, fire is never more than a flick of the finger away these days. But starting a fire 200 years ago? That’s a different story.
One method we’d never heard of was Döbereiner’s lamp, an 1823 invention by German chemist Johann Wolfgang Döbereiner. At first glance, the device seems a little sketchy, what with a tank of sulfuric acid and a piece of zinc to create a stream of hydrogen gas ignited by a platinum catalyst. But as [Marb’s Lab] shows with the recreation in the video below, while it’s not exactly as pocket-friendly as a Zippo, the device actually has some inherent safety features.
[Marb]’s version is built mainly from laboratory glassware, with a beaker of dilute sulfuric acid — “Add acid to water, like you ought-er!” — bathing a chunk of zinc on a fixed support. An inverted glass funnel acts as a gas collector, which feeds the hydrogen gas to a nozzle through a pinch valve. The hydrogen gas never mixes with oxygen — that would be bad — and the production of gas stops once the gas displaces the sulfuric acid below the level of the zinc pellet. It’s a clever self-limiting feature that probably contributed to the commercial success of the invention back in the day.
To produce a flame, Döbereiner originally used a platinum sponge, which catalyzed the reaction between hydrogen and oxygen in the air; the heat produced by the reaction was enough to ignite the mixture and produce an open flame. [Marb] couldn’t come up with enough of the precious metal, so instead harvested the catalyst from a lighter fluid-fueled hand warmer. The catalyst wasn’t quite enough to generate an open flame, but it glowed pretty brightly, and would be more than enough to start a fire.
Hats off to [Marb] for the great lesson is chemical ingenuity and history. We’ve seen similar old-school catalytic lighters before, too.
Continue reading “Lighting Up With Chemistry, 1823-Style”
Much to the chagrin of Eastman Kodak, the world has moved on from chemical photography into the realm of digital, thanks to the ease of use and high quality of modern digital cameras. There are a few photographers here and there still using darkrooms and various chemical processes to develop film, and the most common of these use some type of chemistry based on silver to transfer images to paper. There are plenty of alternatives to silver, though, each with their unique style and benefits, like this rarely-used process that develops film using platinum.
This process, notable for its wide tonal range, delicate highlights, and rich blacks, produces only black and white photographs. But unlike its silver analog, it actually embeds the image into the paper itself rather than holding the image above the paper. This means that photographs developed in this manner are much more resilient and can last for much longer. There are some downsides to this method though, namely that it requires a large format camera and the negatives can’t be modified to produce various sized images in the same ways that other methods allow for. Still, the results of the method are striking for anyone who has seen one of these images in person.
As to why this method isn’t more common, [Matt Locke] describes a somewhat complicated history involving the use of platinum to create commercial fertilizers, which is an identical process to that of the creation of explosives, which were needed in great numbers at the same time this photographic method was gaining in popularity. While the amount of research and development that goes into creating weapons arguably generates some ancillary benefit for society, the effects of war can also serve to divert resources away from things like this.
For several decades now all petrol-driven motor vehicles have had to feature a catalytic converter in their exhaust systems to meet the requirements of emissions legislation. These feature a high surface area coated with platinum, palladium, and rhodium, which catalyses the high-temperature breakdown of the exhaust gasses.
When a vehicle reaches the end of its life its catalytic converter is recycled and those metals are recovered, but this recovery does not account for all the metal. [Cody Reeder] noticed that the weight of platinum in a catalytic converter taken from a scrap vehicle is significantly less than that of a new one. Some of that metal has escaped, so where has it gone?
The answer to that question is that it has become detached from the converter and blown out through the rear of the exhaust pipe. Therefore in the area around a busy highway with many thousands of cars passing there must be a reasonable concentration of platinum. The video below the break details [Cody]’s quest to verify that theory, and it opens with him and a friend sweeping dust from beside a freeway in the early hours. The resulting bags contain a lot of gravel and bits of tire, plus a few cigarette butts and a large amount of very fine dust. He sieves away the debris, and heats a sample of dust in a furnace with a flux mixture containing lead oxide. He hopes that as this oxide degrades to metallic lead it will dissolve any platinum and settle in the bottom of his crucible, and indeed when he pours out the resulting slag there is a bead of lead. Taking away the lead reveals a speck of impure platinum, which he further purifies and assays to determine the percentage of platinum and to detect the other catalyst metals.
He finally arrives at a figure of 6.7 g per ton of his fine-sifted roadside dirt “ore”, a figure which as he points out would be considered quite valuable were it to be encountered in a mine. His process might be a little difficult for individuals with sweeping brushes to hit pay dirt and a modern gold rush to descend on their local Interstate, but it’s not impossible that a highways agency equipped with sweeper trucks could have the metal extracted at a more profitable level.
Continue reading “Mining Platinum From The Road”
[Ben Krasnow] has an inimitable knack for choosing the most interesting concepts for his experiments. We’re sure it’s a combination of base knowledge and epic-curiosity. This time around he’s showing off a vintage cigarette lighter whose quirk is not needing to be “struck” to produce a flame. It’s a catalytic lighter that uses platinum to ignite methanol vapors.
The concept shown in the video below is platinum’s catalyst properties with some types of flammable gasses. The image above shows the cap of the lighter which includes a protective cage around a hunk of fine platinum powder known as platinum black. It is suspended by platinum wire and as the hydrogen passes by the reaction causes the platinum black and wire to glow red-hot.
This simple, quick experiment fills in our own knowledge gaps. We were already familiar with the role that catalytic converters play in automobiles; consuming any unburned hydrocarbons before they exit a vehicle’s exhaust system. We also know the these devices are targets for thieves seeking the platinum (and other metals like palladium and rhodium) found inside. Now we know exactly how catalytic converters work and the integral role that platinum plays in the process. All thanks to [Ben’s] demonstration of how this lighter works.
Now, if you wear a platinum wedding band and your hand passes a jet of hydrogen are you likely to get burned?
Continue reading “The Platinum Catalyst Use In A Vintage Lighter”
The diamond engagement ring is arguably the most universally adopted of all jewelry. It’s artwork that even the most common men and women appreciate, and it’s creation calls for skills that go back centuries. [Jerome Kelty] crafts custom jewelry from platinum. Here’s an in-depth look at his process.
The first step of his Instructable post is so long you might be fooled into thinking it’s the whole post. He shows off the equipment that he used in taking this ring from design to reality — we thought the use of beeswax to pick up small stones is an interesting technique.
Click through the steps to see that he starts with a cad drawing. This model is sent offsite for casting and arrives back as an oversized blank which he then begins to clean up. A range of differend files bring it to its finished shape. He preps the areas where stones will be set. A trip to the buffing wheel gives it the shine it needs before the diamonds are put in place.
Regular Hackaday readers may recognize his name. When [Jerome] isn’t making jewelry he’s building animatronics, like Predator or Stargate replicas.
Continue reading “Tools And Talent For Custom Platinum Jewelry”