The study of bioremediation effect on Cd by immobilized Bacillus subtilis

Bacillus subtilis was immobilized with gelatin, agar-agar and alginate sodium. To chose suitable supports for immobilization by comparing entrapment efficiency,transfer character.The treatment effectiveness of waste water with Cd was compared with immobilized and free Bacillus subtilis and alginate sodium self, The temperature and pH was studied on the influence of the treatment effect of immobilized Bacillus subtilis on waste water with Cd.The results indicated that alginate sodium is the best. The treat effect of immobilized Bacillus subtilis was higher than free Bacillus subtilis notably. And the treat effect is different with the the different concentration of Cd,when concentration of Cd is 1.0 mg/L~(-1)～20 mg/L~(-1),the degradation of Cd is suite cubic cover in 24 h and suit quartic ;pH have some influence on the treat effect, when pH is 5.0～7.0,the Cd degradation is down with pH raise.the temperature is 20 ℃～30 ℃ immobilized Bacillus subtilis have better treatment effectiveness.