Devulcanization of Ground Tires by Different Strains of Bacteria: Optimization of Culture Condition by Taguchi Method
- 112 Downloads
Biological devulcanization of ground tires (GTs) was evaluated by eleven different bacteria belonging to the genera Thiobacillus, Gordonia, Nocardia, Amycolaptopsis and Pseudomonas. The GTs were treated by each bacterium in a mineral medium and devulcanization was measured by increasing the sulfate of the medium and decreasing the sulfur of the GTs. The effects of incubation time (10 and 20 days) and the percent of ground tire in the medium (0.5 and 5 w/v %) on desulfurization were investigated. No significant changes were observed after 10 days of incubation. The total sulfur contents of all bio-treated GTs were decreased by 6–21% in 0.5% GTs after 20 days of incubation. While in 5% GTs, the total sulfur contents were mainly decreased using Thiobacillus ferroxidans DSMZ 583 and PTCC 1647 up to 27 and 15%, respectively. SEM photograph further indicated a good coherency interface between the bacteria and the GTs. Subsequently, Taguchi method was applied for the optimization of the culture condition of DSMZ 583. An L12 orthogonal array was performed by which the effects of eleven factors in two levels were evaluated. It was found that the amount and mesh size of GTs are the most important factors in biological devulcanization of ground tires.
KeywordsDevulcanization Desulfurization Ground tires Optimization Taguchi method
The authors are grateful for financial support from Iran Tire Manufacturing Company under project No. 569001.
- 11.Loffler M, Straube G, Straube E (1993) Biohydrometallurgical technologies. Proceedings of an International Biohydrometallurgy Symposium. Biometallurgical Symposium (Jackson Hole, Wyo. USA)Google Scholar
- 16.Arenskotter M, Baumeister D, Berekaa MM, Potter G, Kroppenstedt RM, Linos A, Steinbuchel A (2001) Taxonomic characterization of two rubber degrading bacteria belonging to the species Gordonia polyisoprenivorans and analysis of hyper variable regions of 16S rDNA sequences. FEMS Microbiol Lett 205:277CrossRefPubMedGoogle Scholar
- 17.Linos A, Berekaa MM, Reichelt R, Keller U, Schmitt J, Flemming HC, Kroppenstedt RM, Steinbüchel A (2000) Biodegradation of cis-1,4- Polyisoprene rubber by distinct actiomycetes: microbial strategies and detailed surface analysis. Appl Environ Microbiol 66:1639CrossRefPubMedPubMedCentralGoogle Scholar
- 22.Roy RK (2001) Design of experiments using the Taguchi approach. Wiley, HobokenGoogle Scholar
- 23.WPCF (1980) Standard methods for the examination of water and wastewater, Chairman JOSEPH J.CONNORS, 15th edn p 438Google Scholar
- 24.Jiang G, Zhao S, Luo J, Wang Y, Yu W, Zhang C (2010) Microbial Desulfurization for NR Ground rubber by Thiobacillus ferrooxidans. J Appl Polym Sci 116:2768Google Scholar
- 29.Franco CMM, Labeda DP (2014) The order Pseudonocardiales. In: Rosenberg E et al The prokaryotes. Springer, Berlin, pp 743–860Google Scholar
- 31.Ghavipanjeh F, Ziaei Rad Zh, Ghavipanjeh F, Pazouki M (2015) Evaluation of Biodevulcanized waste ground tire in revulcanization. Iran J Eng Trans A 28:1Google Scholar