SpudFiles

I got around to making my final electrolysis set up, but i have 1 problem. Im using 2X4 inch plates, total of 6. The base is NaOH in housed in 3in PVC. When i tried running it for more than 10sec, the foam starts coming up through the tube and into the bubbler. How can i get rid of the foam? The main chamber has a Ping Pong ball and a grid right before the tube opening. It has a good enough prodeuction to produce a HHO flame (yay ), but i dont want my electrolyte wasted into the bubbler tap water.

Heres a labled Overall Picture:

hydrogen has been talked about lots here allready

EDIT: doesnt really mean anything after he edited his post

Hmmm... just realized this should be in non spudgun related.

I was mainly asking about the foaming, this is for a science fair, so i was asking.

how many amps do you have running through it? and does it get really hot by the time the bubbles start forming?

Im not sure how many amps are running through it, im using a drill battery 14.4V. I should be able to pick up an ATX power Supply soon. Im suspecting its drawing alot of current because the wires get hot after a good 10secs, and its AWG 12 copper wire. I havnt let it run long enough to be able to feel the heat through the PVC.

Im not able to calculate how much the cell is attempting to draw, as my multimeter has a dead battery ;(.

The foam almost instantly forms last time i checked it without the cap.

mabe if you keep the small pipe there really cold or something it will "bust" the bobbles. i dont really know for sure
but water is not making bobbles when boiled clean it is probably your ingredients to the water.
try find something else or use less of it.

use a really fine mesh in the middle of the little pipe many layers of mesh should do the trick.
( i dont really know if it is mesh i mean like a fine coffee filter )

i think ile just add [another] foam .arrester near the gas output

I would make a nipple at the end of the tube in the electrolyzer, so you can screw on a piece of coffeefilter (burst-disc concept). I had this problem too

the clean out cap has a square opening, so what if i just glued on a cofee filter there?

How much air space is there above the electrolyte? You might trying increasing it, by decreasing the amount of electrolyte in the chamber. The air space gives the bubbles someplace to pop.

Sounds like you need a good way to limit the current to the cell. Too much current aggravates the foaming problem and produces too much heat.

Soooo, need a cheap, high power, relatively low resistance resistor. Try lightbulbs. A 100Watt light bulb has about 150 ohms resistance and will handle 100 watts of power (well duh). So, a 100W bulb is essentially a big ass ballast resistor. Lower watt bulb have higher resistance. Try wiring a light bulb socket in series with the battery and cell. Try a couple different light bulb sizes until you get decent gas production without excessive foaming or heating.

The ballast resistor from a car is another possiblity. IIRC, they are ~10 ohms and 5 or 10 watts. (I'm not sure if modern cars still use ballast resistors.)

If you knew what the resistance of the cell was then it would be a heck of a lot easier to figure out the correct size for tha ballast resistor. And, you could set things up so you have the proper voltage across the cell (14V is way too much voltage for a single cell).

Oh yeah, almost forgot. Another way to limit both the foaming and heat generation is to just dilute you electrolyte. Try cutting your electrolyte 1:1 with water.

hmm.... I Have 2 10 ohm 10W wirewound resistor ( i tried to use it for my other supply, but i put it on wrong line), ile try those, Im not going to use battery anymore.
Ile get the supply tomorrow and try it on 3.3v and 5v line.

Weird. I measured resistance of the 2 resistors, that came out to 23 ohms, so pretty accurate. I measure the resistance of the cell, and its erading 80 Ohms. I tried with a 16.5v 4.5A computer adapter, short circuit protection kicks in.

With the 2 resistors in parrallel to cell, they get hot. The cell resistance cant be right, otherwise it would work.

Well i got new battery's, the cell resistance is 2.3 Ohms.

I also tried coffee filter, it didnt work, it slows it down, but it gets right through.

rp181 wrote:Well i got new battery's, the cell resistance is 2.3 Ohms.

I also tried coffee filter, it didnt work, it slows it down, but it gets right through.

OK, so now the reason why the power supply kicks off is clear.

16.5V/2.3Ohm = 7.2 Amps

The easiest thing to do is to just dilute your electrolyte. Cut it 1:1 with water and the cells resitance will go to ~4.6 ohms. Your current draw will be 3.6 amps, your power supply will be happy, you'll generate half as much heat and you'll greatly reduce foaming. (Of course, you'll also reduce the rate of gas generation.)

Any luck with the lower voltage power supply?

i got a 145W ATX power supply (its really old) which is this:
http://www.hcditrading.com/Shop/Control ... /SFV/29664

Now i cant turn it on ;(

i plugged it in and tried both green to black and green to black with a 10ohm load of the red (5v) line.

the only thing that happens is a "squeaking" ever 1 sec. whenever green is connected to black.

Any ideas?

You may have to load all of the power supply lines to get any of them to work. 100W light bulbs to the rescue.