The removal of bacteria by modified natural zeolites.
The removal effect of natural and modified zeolites containing different heavy metals (Ni2+, Zn2+, Fe3+ and Cu2+) on pure cultures of Escherichia coli and Staphylococcus aureus in a solid medium was evaluated in this work. These experiments were carried out in a continuous mode treating municipal wastewater. Faecal coliform species and Pseudomonas aeruginosa were identified. The rate constants of heavy metal lixiviation were determined using a first order kinetic model. The removal effect of modified natural zeolites in both a solid medium and in continuous mode showed an increased elimination of the bacterial population. The results established a decreasing order of the removal effect as follows: Cu2+ > Fe3+ > Zn2+ > Ni2+. The best performance of columns was obtained for inlet bacterial concentrations below 10(6) cells/100 ml. Most of the identified bacterial species were affected by copper modified zeolites, although Serratia marcescens presented the highest sensitivity and Klebsiella pneumoniae the greatest resistance.
Milán
Z
Z
Departamento de Estudios sobre Contaminación Ambiental (DECA), Centro Nacional de Investigaciones Científicas (CNIC), P.O. Box 6990, La Habana, Cuba.
de Las Pozas
C
C
Cruz
M
M
Borja
R
R
Sánchez
E
E
Ilangovan
K
K
Espinosa
Y
Y
Luna
B
B
D004926:Escherichia coli; D005243:Feces; D007700:Kinetics; D019216:Metals, Heavy / Q000737:chemistry*; D008962:Models, Theoretical; D011550:Pseudomonas aeruginosa; D013211:Staphylococcus aureus; D014876:Water Pollution / Q000517:prevention & control; D018508:Water Purification / Q000379:methods*; D017641:Zeolites
D019216:Metals, Heavy; D017641:Zeolites