Biological degradation and mineralization of tetracycline antibiotic using SBR equipped with a vertical axially rotating biological bed (SBR-VARB)

Abstract

Tetracycline (TC) is a widely used antibiotic with a complex aromatic chemical structure and is highly resistant to biodegradation. In this study, an SBR equipped with a vertical axially rotating biological bed (SBR-VARB) was used for the biodegradation and mineralization of TC. SBR-VARB showed high efficiency in removing TC (97%), total phenolic compounds (TP) (95%), and COD (85%) under optimal operating conditions (TC = 50 mg/L, HRT = 1.75 d, and OLR = 36 g COD/m3 d). The SBR-VARB was able to treat higher concentrations of TC in shorter HRT than reported in previous studies. The contribution of VARB to improve SBR efficiency in removing TC, TP, and COD was 16, 36, and 48%, respectively. Intermediate compounds formed during the biodegradation of TC were identified using GC–MS under the optimal operating conditions of the bioreactor. These are mainly organic compounds with linear chemical structures. Based on the complete biodegradation of TC under the optimal operating conditions of the bioreactor, 93% and 36% of the chlorine and nitrogen atoms in the chemical structure of TC appeared in the wastewater, respectively. According to the sequence analysis of 16SrDNA, Pseudomonas sp., Kocuria Polaris, and Staphylococcus sp. were identified in the biofilm of VARB and the suspended biomass of the bioreactor. Therefore, SBR-VARB showed high efficiency in the biodegradation and mineralization of TC and can be used as a suitable option for treating wastewater containing antibiotics and other toxic compounds.

Highly Efficient Photocatalytic Degradation of Tetracycline by Modifying UiO-66 via Different Regulation Strategies

“…In recent years, due to the expanding demand of medicine and pigment printing and dyeing industry, a large amount of chemical wastewater containing organic dyes has been produced, which creates the problem of organic pollutants harming human life. 1 Many physical and chemical technologies have been developed for the treatment of wastewater, such as membrane filtration, 2 Fenton oxidation, 3 biological treatment, 4 and adsorption, 5 However, most dye molecules possessed large conjugated structures that cannot be completely removed, and had disadvantages such as low efficiency, high cost, and secondary pollution. Photocatalysis technology could produce strong oxidizing free radicals under light conditions and completely degrade organic pollutants into CO 2 , H 2 O, and inorganic salts, without secondary pollution.…”