Degradation of trans-chlordane using elemental iron

• Main Authors: Auresenia, Joseph L., Moradas, Gerly, Gallardo, Susan M., Guieysse, Benoit
• Format: text
• Published: Animo Repository 2005
• Subjects: Chlordan; Surface active agents; Dechlorination; Chemical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/11974
• Institution: De La Salle University

Dechlorination of chlordane by reductive dechlorination using elemental iron was studied. Batch experiments in small vials were performed to test the performance of elemental iron to dechlorinate chlordane. Different reacting conditions were tested in four different sets of experimental runs. The first set of experimental runs determines the effect of buffer addition; the second set determines the effect of acidification and addition of deoxygenating agent. The third set determines the effect of iron concentration and addition of surfactants and the fourth set determines the effect of different types of surfactants. It is found that with elemental iron only, chlordance concentration decrease was negligible. Addition of buffers resulted in 10 to 20% reduction in chlordance concentration. When acidification to pH 2 was done the reduction was increased to 40%. Addition of deoxygenating agent did not improve the reduction percentage. Addition of surfactants together with acidification increased the reduction of chlordane concentration to more that 90% in 24 hrs and to around 98% in 48 hrs. The reduction in chlordane concentration was accompanied in the increase of chloride concentration. Based on the chloride ion amount computed from lost chloradane, the dechlorination products was also monitored using GC-MS. It was found the major dechlorination products were organic molecules with 3 to 7 chloride atoms. Highly chlorinated product peaks decreased and slightly chlorinated product peaks increased when the reaction time was extend to 48 hrs/ This showed that reductive dechlorination was the process responsible for the loss in chlordane.