|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Deriving Value from Challenging Waste Streams: Recycling and Sustainability Joint Session
||Bacterial Degradation of Free Cyanide in Alkaline Medium Using Bacillus Licheniformis Strain
||Amzy Tania Vallenas Arévalo, Carlos Gonzalo Alvarez Rosario, Denise Crocce Romano Espinosa, Jorge Alberto Soares Tenório
|On-Site Speaker (Planned)
||Amzy Tania Vallenas Arévalo
Cyanide is a toxic chemical used in mining industry to recover gold and silver in leaching process. Effluents containing cyanide can be treated by bioremediation instead of physical and chemical processes which are often more expensive and less efficient. This study evaluated the capacity for free cyanide degradation of a <I>Bacillus licheniformis</I> strain previously isolated from an abandoned gold mine. First, bacterial growth in LB medium through OD<SUB>600</SUB> was studied. Then, bacteria was adapted to grow on alkaline medium using CAPS buffer to keep pH10. Finally, cyanide degradation assays were performed using a 500mgL<SUP>-1</SUP> KCN pH10 50mM CAPS solution. Free cyanide was measured using a polarographic method. Temperature influence was evaluated at 27, 32 and 37°C. Results showed that <I>B. licheniformis</I> was able to degrade 99% of free cyanide after 5 days of incubation and works better at 32°C showing the strain potential for cyanide biotreatment in mining industry.