Sorption and biodegradation of propylparaben in greywater by aerobic attached-growth biomass

Haihong Song; Yuval Alfiya; Yael Dubowski; Eran Friedler

doi:10.1016/j.scitotenv.2017.04.032

Sorption and biodegradation of propylparaben in greywater by aerobic attached-growth biomass

Sci Total Environ. 2017 Nov 15:598:925-930. doi: 10.1016/j.scitotenv.2017.04.032. Epub 2017 Apr 28.

Authors

Haihong Song¹, Yuval Alfiya¹, Yael Dubowski¹, Eran Friedler²

Affiliations

¹ Department of Environmental, Water and Agricultural Engineering, Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa, Israel.
² Department of Environmental, Water and Agricultural Engineering, Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa, Israel. Electronic address: eranf@tx.technion.ac.il.

PMID: 28458210
DOI: 10.1016/j.scitotenv.2017.04.032

Abstract

Greywater (GW) is becoming an important alternative water source for non-potable purposes, but requires treatment to remove contaminants, including micropollutants that in GW mainly originate from personal care products. Biofilters are commonly used for onsite GW treatment, but there are still significant knowledge gaps regarding their ability and mechanism of micropollutants removal. This study investigates the removal of propylparaben (PPB) by aerobic attached-growth biomass, quantifying the kinetics and the interplay between sorption and biodegradation. The ability of biomass, collected from a pilot scale biofilter treating real GW, to eliminate PPB from both synthetic greywater (SGW) and deionized (DI) water was studied in laboratory batch experiments. Elimination of PPB was found to proceed via sorption to biomass followed by biodegradation. Sorption of PPB by biomass in SGW and in DI water exhibited similar kinetics, fitting Langmuir isotherm with the maximum adsorbed amount of 9.8mg_PPB g_biomass^-1. PPB biodegradation exhibited first-order kinetics in both SGW and DI water, with a 30h lag-phase in SGW and no lag-phase in DI water. This difference is attributed to presence of readily-biodegradable organic matter in the SGW. Actual PPB degradation rate in both cases (excluding the lag phase in SGW) was very similar, 62mg_PPB g_biomass^-1d^-1, yielding almost full mineralization. These findings show the relative contribution of the major processes involved in PPB elimination by biofilters and can be applied for designing GW treatment units.

Keywords: Greywater; Micropollutants; Personal care products; Propylparaben; Transesterification.