Common names for chemicals and selection of appropriate stainless steel grades

Introduction

The table is referenced by the common name.
The 'appropriate grades' notes are taken from the Avesta Sheffield Corrosion Handbook and are shown for general guidance only.
Specific grade selections should be rechecked with corrosion tables. A link to the BSSA web site article that describes where to find the corrosion tables on the Outokumpu Stainless web site can be found in the Related Links section of this article.

Common chemical names

Common name	Chemical name	Formula	Grade selection
alum	potassium aluminium sulphate	KAl(SO₄)₂	304 or 316 useful at all concentrations, up to 50C
aqua fortis	nitric acid	HNO₃	Selection of stainless steels for handling nitric acid (HNO₃)
aqua regia	nitric and hydrochloric acid mixture	HNO₃ and HCl	Likely to attack most stainless steels This mixture is used for dissolving gold.
bleach	sodium hypochlorite	NaOCl	Selection of stainless steels for handling sodium hypochlorite (NaOCl) - Bleach
caustic potash	potassium hydroxide	KOH	similar selection as for sodium hydroxide
caustic soda	sodium hydroxide	NaOH	Selection of stainless steels for handling sodium hydroxide (NaOH)
chromic acid	chromium trioxide	CrO₃	304 or 316 useful up to 40%, 20C
ethanol (alcohol)	ethyl alcohol	C₂H₅OH	304 or 316 useful at all concentrations, up to boiling point
glycol	ethylene glycol (anti-freeze preparations)	C₂H₄(OH)₂	304 or 316 useful at all concentrations at ambient (or lower) temperatures
gypsum	calcium sulphate	CaSO₄	304 or 316 useful at all concentrations, up to boiling point
Javelle (javel) water	sodium hypochlorite	NaOCl	Selection of stainless steels for handling sodium hypochlorite (NaOCl) - Bleach
Labarraque's solution	sodium hypochlorite	NaOCl	Selection of stainless steels for handling sodium hypochlorite (NaOCl) - Bleach
marine acid	hydrochloric acid	HCl	Selection of stainless steels for handling hydrochloric acid (HCl)
methanol (alcohol)	methyl alcohol	CH₃OH	304 or 316 useful at all concentrations, up to boiling point
muriatic acid	hydrochloric acid	HCl	Selection of stainless steels for handling hydrochloric acid (HCl)
oil of vitriol	sulphuric acid	H₂SO₄	Selection of stainless steels for handling sulphuric acid (H₂SO₄)
oleum	concentated sulphuric acid	H₂SO₄	Selection of stainless steels for handling sulphuric acid (H₂SO₄)
rock salt	sodium chloride	NaCl	Crevice and pitting corrosionhazard with most stainless steels, depending on conditions
salt acid	hydrochloric acid	HCl	Selection of stainless steels for handling hydrochloric acid (HCl)
spirit of salt	hydrochloric acid	HCl	Selection of stainless steels for handling hydrochloric acid (HCl)
sulphurated hydrogen	hydrogen sulphide	H₂S	Can be a pitting or (stress corrosion cracking hazard) to non-molybedum alloyed stainless grades
wood acid	acetic acid (mainly)	CH₃COOH	Selection of stainless steels for handling acetic acid (CH₃COOH)

Source: http://www.bssa.org.uk/

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