The effect of chemical sulfide oxidation on the oxygenic activity of an alkaliphilic microalgae consortium deployed for biogas upgrading
Por:
Ramírez-Rueda A., Velasco A., González-Sánchez A.
Publicada:
1 ene 2020
Resumen:
The oxygenic photosynthetic activity (OPA) of an alkaliphilic microalgae consortium was evaluated at different concentrations of dissolved sulfide under room temperature and well-defined conditions of irradiance and pH in a tubular closed photobioreactor. The kinetic assays showed that it was optimal at a sulfide concentration of 3.2 mg/L under an external photosynthetically active radiation of 50 and 120 µE/m2 s together with a pH of 8.5 and 9.2. In contrast, the oxygenic photosynthetic activity was insignificant at 15 µE/m2 s with a pH of 7.3, both in the absence and presence of sulfide. Consecutive pulse additions of dissolved sulfide evidenced that the accumulation rate of dissolved oxygen was decreased by the spontaneous chemical oxidation of sulfide with dissolved oxygen in alkaline culture media, mainly at high sulfide levels. At 3.2 mg/L of sulfide, the oxygenic photosynthetic activity was improved by around 60% compared to the treatment without sulfide at external irradiances of 120 µE/m2 s, 30 °C, and pH of 8.5 and 9.2. Additionally, an even higher OPA enhancement (around 85%) was observed in the same previous conditions but using 16 mg/L of sulfide. Thiosulfate was the major end-product of sulfide by oxic chemical reaction, both in biotic and abiotic assays with yields of 0.80 and 0.68, respectively. © 2020 by the authors.
Filiaciones:
Ramírez-Rueda A.:
Univ Nacl Autonoma Mexico, Inst Ingn, Ciudad Univ, Mexico City 04510, DF, Mexico
Velasco A.:
Univ Nacl Autonoma Mexico, Inst Ingn, Ciudad Univ, Mexico City 04510, DF, Mexico
González-Sánchez A.:
Univ Nacl Autonoma Mexico, Inst Ingn, Ciudad Univ, Mexico City 04510, DF, Mexico
Gold
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