Inhibition of bacterial activity in acid mine drainage

Acid mine drainage water give rise to rapid growth and activity of an iron- and sulphur- oxidizing bacteriumThiobacillus ferrooxidians which greatly accelerate acid producing reactions by oxidation of pyrite material associated with coal and adjoining strata. The role of this bacterium in production of acid mine drainage is described. This study presents the data which demonstrate the inhibitory effect of certain organic acids, sodium benzoate, sodium lauryl sulphate, quarternary ammonium compounds on the growth of the acidophilic aerobic autotroph Thiobacillusferrooxidians. In each experiment, 10 milli-litres of laboratory developed culture ofThiobacillus ferrooxidians was added to 250 milli-litres Erlenmeyer flask containing 90 milli-litres of 9-k media supplemented with FeSO₄ 7H₂O and organic compounds at various concentrations. Control experiments were also carried out. The treated and untreated (control) samples analysed at various time intervals for Ferrous Iron and pH levels. Results from this investigation showed that some organic acids, sodium benzoate, sodium lauryl sulphate and quarternary ammonium compounds at low concentration (10-2 M, 10–50 ppm concentration levels) are effective bactericides and able to inhibit and reduce the Ferrous Iron oxidation and acidity formation by inhibiting the growth ofThiobacillus ferrooxidians is also discussed and presented