Guideline: 1. Dissolve 40 g of ferric chloride (anhydrous) in 101.5 mL of water. 2. You can re-use the solution many times, but etching time gets longer with greater use.
Cautions 1. Do NOT use metallic containers trays or spoons for handling the ferric chloride liquid. 2. Do not get this on clothing - It stains badly. 3. Do not empty it into a stainless steel kitchen sink. - It attacks stainless steel. 4. Powder form releases significant heat when you dissolve it is water. Be cautious.
CAS Number: 7705-08-0 UPAC names Iron(III) chloride Iron trichloride Other names: Ferric chloride
Iron(III) chloride, also called ferric chloride, is an industrial scale commodity chemical compound, with the formula FeCl3 and with iron in the +3 oxidation state. The colour of iron(III) chloride crystals depends on the viewing angle: by reflected light the crystals appear dark green, but by transmitted light they appear purple-red. Anhydrous iron(III) chloride is deliquescent, forming hydrated hydrogen chloride mists in moist air. When dissolved in water, iron(III) chloride undergoes hydrolysis and gives off heat in an exothermic reaction. The resulting brown, acidic, and corrosive solution is used as a flocculants in sewage treatment and drinking water production, and as an etchant for copper-based metals in printed circuit boards. Anhydrous iron(III) chloride is a fairly strong Lewis acid, and it is used as a catalyst in organic synthesis.
Uses: 1. Used in anhydrous form as a drying reagent in certain reactions. 2. Used in water and wastewater treatment to precipitate phosphate as iron(III) phosphate. 3. Used by blade smiths and artisans in pattern welding to etch the metal, giving it a contrasting effect, to view metal layering or imperfections. 4. Necessary for the etching of photogravure plates for printing photographic and fine art images in intaglio and for etching rotogravure cylinders used in the printing industry. 5. Used to make printed circuit boards (PCBs). 6. Sometimes used in a technique of Raku ware firing, the iron coloring a pottery piece shades of pink, brown, and orange. 7. Used to test the pitting and crevice corrosion resistance of stainless steels and other alloys. 8. Used in veterinary practice to treat over cropping of an animal's claws, particularly when the over cropping results in bleeding. 9. Used in an animal thrombosis model. 10. A component of modified Carnoy's solution used for surgical treatment of keratocystic odontogenic tumor (KOT) 11. Used to detect the presence of phenol compounds in organic synthesis e.g.: examining purity of synthesized Aspirin.