BAKER HUGHES - Drilling Fluids Reference Manual

Baker Hughes Drilling Fluids
Compounds which have easily replaceable hydrogen ions are called acids (see Table 5-1)
Name
Table 5-1
Hydrochloric or Muriatic Acid
Carbonic Acid
Hydrofluoric Acid
Acetic Acid
Oleic Acid
Naphthenic Acid
Common Acids
Formula
HCl
H 2 CO 3
HF
H 3 CCOOH
CH 3 (CH 2 ) 7 CHCH(CH 2 ) 7 COOH
C 10 H 7 COOH
Compounds which can react with and accept hydrogen ions are called bases (see Table 5-2).
Table 5-2 Common Bases
Name
Formula
Caustic Soda, Caustic, or Sodium Hydroxide NaOH
Soda Ash, Sodium Carbonate
Potash, Pearl Ash, Potassium Chromate Na 2 CO 3
Potassium Hydroxide
K 2 CO 3
Lime Hydrate or Lime
KOH
Ca(OH) 2
Acids can react with bases to form salt and water. As an example, hydrogen chloride reacts with
sodium hydroxide to form sodium chloride plus water. This reaction can be represented by the
equation,
HCl + NaOH → NaCl + H 2 O
As discussed earlier under ionic bonds, sodium chloride, table salt, can be represented by,
Na + Cl –
The sodium ion and chloride ion are strongly attracted to one another through coulombic attraction.
The two ions separate when dissolved in water. The solvent, in this case water, disassociates the salt
crystal into its constituent ions (see Figure 5-4). This is possible due to the water molecule dipoles
orienting around the individual ions as shown in Figure 5-5
Baker Hughes Drilling Fluids
Reference Manual
Revised 2006 5-9