Adsorption behavior of sulfamethazine in an activated sludge process treating swine wastewater

Abstract

Swine wastewater is an important pollution source of antibiotics entering the aquatic environment. In this work, the adsorption behavior of sulfamethazine (SMN), a commonlyused sulfonamide antibiotic, on activated sludge from a sequencing batch reactor treating swine wastewater was investigated. The results show that the adsorption of SMN on activated sludge was an initially rapid process and reached equilibrium after 6 hr. The removal efficiency of SMN from the water phase increased with an increasing concentration of mixed liquor suspended solids, while the adsorbed concentration of SMN decreased. Solution pH influenced both the speciation of SMN and the surface properties of activated sludge, thus significantly impacting the adsorption process. A linear partition model could give a good fit for the equilibrium concentrations of SMN at the test temperatures (i.e., 10, 20 and 30°C). The partition coefficient (K d ) was determined to be 100.5 L/kg at 20°C, indicating a quite high adsorption capacity for SMN. Thermodynamic analysis revealed that SMN adsorption on activated sludge was an exothermic process. This study could help to clarify the fate and behavior of sulfonamide antibiotics in the activated sludge process and assess consequent environmental risks arising from sludge disposal as well.

Removal of concentrated sulfamethazine by acclimatized aerobic sludge and possible metabolic products

“…Liquid chromatography–mass spectrometry (LC/MS, 6430 Triple Quad LC/MS; Agilent Technologies, Santa Clara, California, USA) was used to identify biological metabolic intermediates of SMZ. The analytical methods used for LC/MS measurement of the aqueous samples were described previously ( Avisar, Lester & Mamane, 2010 ; Ben et al, 2014 ; Garcia-Galan et al, 2011 ; Mansour et al, 2014 ; Yang et al, 2011 ; Yang et al, 2012 ). An Agilent TC-C 18 column (2.1 × 50 mm, 1.8 µm particle size) and a UV detector at a wavelength of 267 nm were employed.…”

Bioprocessing for elimination antibiotics and hormones from swine wastewater

“…SMs, one of the major antibiotics in swine wastewater, is characterized by easy migration and high bio-toxicity compared to other veterinary antibiotics. Their behaviour in wastewater has been the subject of several analyses (Baquero et al, 2008;Ben et al, 2014;Chen et al, 2012b;Xian et al, 2010). SMs dissolve relatively well in water with low logKow (0.19-0.89), and their biosorption removal from wastewater is expected to have a low potential for hydrophobic partitioning.…”

“…This has been confirmed by the research of Abegglen et al (2009), Yang et al (2011), andYang et al (2012), they concluded that SMs were little adsorbed onto sludge. Similarly, Ben et al (2014) assessed the adsorption behavior of SMs in activated sludge from swine wastewater, and discovered that only about 5% of SMN was adsorbed on the activated sludge when it reached equilibrium after 6 hrs. Zhou et al (2011) also drew a similar conclusion that a large proportion of SMN was found in effluents while only a small ratio was found in the sludge after treatment by activated sludge processes.…”

“…80% (Li et al, 2011) By contrast, the secondary activated sludge process is the main stage for the elimination of antibiotics and hormones by both biosorption and biodegradation (Li & Zhang, 2010;Yang et al, 2011;Zhou et al, 2013). Biosorption onto activated sludge is believed to be the first and most rapid step and more important than the following biodegradation process (Ben et al, 2014;Yang et al, 2012;Yang et al, 2011). For example, a research on the behavior of sulfamethazine (SMZ) in an activated sludge process indicated a rapid and high adsorption capacity for SMZ in 6 h, although SMs were reported to be absorbed less on activated sludge (Ben et al, 2014).…”

Improving hydrolysis acidification by limited aeration in the pretreatment of petrochemical wastewater

“…The degradation process can be divided into 3 phases. The COD dropped quickly in the first 2 h, due to the absorption of the activated sludge (Ben et al, 2014). In the next 10 h, the COD decreased at a slower speed than the first 2 h by the oxidization of activated sludge.…”