Sciencemadness Discussion Board

Acetylides and carbide lamps

inspector071 - 2-5-2012 at 20:32

Quite a few years ago, my uncle gave me a carbide lamp, one he used to take raccoon hunting. The lamp with its large reflector was bright enough to spot raccoons high in the tree tops after a dog has treed it. I bought a couple more off eBay becase I thought they were cool, and I wanted to take one caving. I ordered a couple of cans of calcium carbide and I was set. Stuff like this is what really got me interested in sciences at a young age, and has led to my choice to major in chemistry in college.

I recently pulled out my carbide lamps to use as a bubbler for making various acetylides: cupric, cuprous, and hopefully some silver. The lamp works great as a bubbler, and my syntheses have gone very well. However, as I was making a few miligrams of cupric acetylide, I wondered if the brass composition of the lamp could be producing acetylides inside of the lamp.

From reading, I found that plants manufacturing and working with acetylene learned to stay away from copper pipes. The sensitive acetylides could form inside the pipes and cause large explosions, especially considering the gas the pipes were transporting is quite flammable. When cleaning my lamp, I usually just let some vinegar sit in it to dissolve the calcium hydroxide that forms and call it a day. Tonight, after use, I took it apart and cleaned it more thoroughly and found a layer of a fine black substance, not unlike the cupric acetylide I had just made. Could copper acetylides be forming in this basic, hot environment? Have there ever been reports of a miners lamp spontaneously exploding? I'm going to set aside the substance I can scrape out and see if it resembles acetylide when put to a match and update.