Effect of pH, Salinity, Dye, and Biomass Concentration on Decolourization of Azo Dye Methyl Orange in Denitrifying Conditions

A recent study by the current authors found simultaneous decolourization and mineralization of high concentrations of methyl orange (500 mg/L) in an anoxic up-flow reactor in denitrifying conditions. To supplement this work, various batch reactor studies were carried out to study the effect of (i) pH (4 to 9), (ii) salinity (1 g/L NaCl to 10 g/L NaCl), (iii) dye concentration (100 mg/L to 1000 mg/L), (iv) biomass concentration (0.3 g/L to 0.21 g/L); on the process, and (iv) kinetics of decolourization in denitrifying conditions. The adapted mixed microbial consortium, originally sourced from the activated sludge process, was capable to simultaneously remove colour, COD, and NO3−-N under denitrifying conditions, even at high methyl orange (MO) concentrations of 1000 mg/L at 84 h. Although the decolourization was possible for wide ranges of pH, better performance was obtained at alkaline pH levels. The decolourization performance increased when biomass concentration increased and was not affected by salinity up to 10 g/L NaCl. This may have been due to enhanced lyses of biomass at high salt concentrations. Batch kinetic studies showed that the MO decolourization followed first-order kinetics, with a rate constant of 0.0612 h−1. Results of this study may help in the future application of textile effluent treatments, using a high biomass retention reactor in denitrifying conditions with minimum sludge disposal costs

sj-docx-1-ijl-10.1177_15347346221128651 - Supplemental material for Dehydrated Human Amnion/Chorion Membrane Allografts as an Adjunct Wound Healing Therapy in Diabetic Rats

Supplemental material, sj-docx-1-ijl-10.1177_15347346221128651 for Dehydrated Human Amnion/Chorion Membrane Allografts as an Adjunct Wound Healing Therapy in Diabetic Rats by Chirayu Padhiar, Muthuraman Muthuchamy, Vignesh Ganesan, Swathi Desireddy, Mayur Abhaya, Ramanujam Siva and Kalaivani Periyathambi in The International Journal of Lower Extremity Wounds</p