Acetylene Gas from Sea Shells and Driftwood

Video Description

Head to https://squarespace.com/hyperspacepirate to save 10% off your first purchase of a website or domain using code HYPERSPACEPIRATE In this video I'll show how to make Acetylene gas (C2H2) from Seashells and Driftwood. Acetylene gas is formed when Calcium Carbide (CaC2) comes into contact with water. Calcium Carbide can be made by reacting Calcium Oxide (CaO) with Carbon at temperatures in excess of 2,000C. The Calcium Oxide is produced by thermal decomposition of Calcium Carbonate (CaCO3), aka. Limestone. Seashells are mostly made of Calcium Carbonate, so they're baked in a propane furnace to produce the Calcium Oxide. The Carbon in the reaction comes from Charcoal, which is made by thermal decomposition of the driftwood. When wood is heated in the absence of oxygen, it releases a whole soup of volatile compounds including Methane, Carbon Monoxide, Carbon Dioxide, various other hydrocarbons, Methanol Vapor, Water Vapor, and also some tar and other goo. What's left behind is Charcoal, which is almost entirely Carbon, but with trace amounts of Potassium, Sodium, Sulfur, Phosphorous and a few other compounds. Once the Calcium Oxide and Carbon are produced, they're ground up together in a blender to make sure they're mixed as well as possible and have extremely small particle sizes to make the reaction progress easier. The temperature required for the reaction is too hot for an air breathing flame, and I don't have an oxy-fuel system, so I used an Electric Arc Furnace to heat the powder mixture. The arc was supplied with 31VAC from a winding added to the transformer of a 110/220V converter box, which can handle up to 3 kW. Later, I had to reduced the voltage to 15VAC after melting off the windings. There's no obvious visual indicator that Calcium Carbide has been formed, but due to the impurities in the reagents, it has a very prominent garlic-like smell that makes its presence obvious. Once the Carbide is formed, it can be added to water, and Acetylene gas will bubble out. The gas can be collected in a balloon or dissolved in Acetone, but it's unsafe to store it under pressure because it becomes unstable over 3-4 atm. If you have access to elemental Calcium, it's much easier to make the Calcium Carbide, because it only requires mixing with charcoal powder and heating in a test tube with a propane torch.