Carbon electrodes !!!!

[chuinhen]

Other then batteries ! !

where can we get Carbon electrodes ??

 

And How to obtain it !?!?!

[insane_alien]

scrape the wood off of pencils and use the graphite from that. or you could buy them from a chemistry supplier.

[YT2095]

why don`t you buy some gouging rods from a welding/hardware store?

[chuinhen]

How many percent of Carbon in the pencil lead ??

[gcol]

Pencil leads are a mixture of the natural mineral graphite, plus varying amounts of clay. Soft pencil leads, 5B for example, have more carbon than hard leads, 5H. So cant say how much carbon. It varies. Pure graphite (100% carbon) is too soft for practical pencils.

[woelen]

I have my carbon rods from batteries, but from a special type. These batteries contain long rods (8 ... 9 cm) with a diameter of 8 mm. The standard AA cells, A cells and so on, contain very small rods. The battery, I am referring to, has 4 of these rods, internally it contains 4 cells, each cell delivering 1.5 V of output voltage.

 

http://www.apexbattery.com/accessories-6-volt-lantern-battery-miscellaneous.html

 

These types of batteries provide an affordable and easy to obtain source of large graphite rods. It only takes an hour of (dirty!!!) and careful work to get these rods out of the battery.

[chuinhen]

the carbon i obtained from the 9V battery ,

 

rupture / breaks up , duriang electrolysis !!!!

 

Isn't it inert !?!?!?!

[woelen]

This is a very common effect. Graphite rods tend to erode during electrolysis and pulverise. It is inert, but particles of graphite do not stick together very strongly. The current density should be kept below 100 mA/cm² for graphite anodes, or even better, below 50 mA/cm². At higher current densities, the erosion becomes really excessive.

 

Also, oxygen formation at the electrodes enhances erosion strongly. This is the case, if the cell operates at too high a voltage. For good electrolysis, you need to work with solutions as concentrated as you can get them (allowing lower voltage for the same current and having less oxygen production at the anode) and you need to compute how much current may go through them by estimating the total area of the electrode, which is immersed in the liquid. With some form of current control the electrolysis cell can be kept in its correct operation domain. Using a voltage source of e.g. 9V or even 12V really kills your graphite electrodes.

[YT2095]

another Tip I discovered recently whilst drying my 12mm carbon electrodes, even if you wash then after they are NOT clean!

the cathode will grow crystals on the outside after a few days, you wash them off and the same happens again, so I decided to soak them in water, and to my amazement the water went dark brown in a few hours.

I soaked them individualy and it`s the Anode that`s responsible for the brown color.

 

so if you do use carbons, label them up what they were used for and don`t use them for anything else, they`re irreversibly contaminated.

 

sulphite soaks and nitric soaks won`t shift it!