Retention of organics and degradation of micropollutants in municipal wastewater using impregnated ceramics

Lev Tsapovsky,Vitaly Gitis,Gadi Rothenberg,Michal Simhon,Vincenzo Roberto Calderone

doi:10.1007/s10098-020-01813-2

Abstract

Pesticides, personal care products, industrial chemicals often pollute surface- and groundwater sources. With trace concentrations and low molecular weights, these micropollutants (MPs) easily penetrate through treatment systems and impose a real health threat on drinking water consumers. The absence of a dedicated MP-retaining treatment technology at water treatment plants results in a constant consumption of MP-contaminated water. Advanced oxidation processes, and in particular the Fenton reaction, can successfully degrade MPs if other, larger, fractions of organics are retained. Here, we suggest a novel combined two-stage retention–degradation approach. Ceramic membranes retain large organics such as bovine serum albumin (BSA). Fenton processes disintegrate nonretained MPs such as methylene blue (MB) and bisphenol A (BPA) that penetrate through the membrane. The efficiency of the suggested approach is high. Single-layered ultrafiltration membrane retains more than 96% BSA and degrades 40–50% of MB and BPA. The degree of degradation depends on both the impregnated metal oxide and the concentration of hydrogen peroxide. Vanadium-based catalysts retain more than 90% MPs but leach into permeate. Ferric oxides were the only stable catalysts that performed better in membranes than when impregnated on α-Al2O3 pellets. A combined retention–degradation can be optimized to result in superior degree of retention. Catalytic ceramic membranes can retain large organic molecules and decompose MPs simultaneously. Three parameters affect the process efficiency: the dynamics of the influent fluid, the catalyst dose and the contact time.Graphic abstract

Highlights

Trace organics such as pesticides, pharmaceuticals, personal care products and polymer additives are repeatedly found in surface- and groundwater sources (Ribeiro et al 2015)
The bovine serum albumin (BSA) was used as a representative organic macromolecule found in municipal wastewater
The BSA retention level of one-layered simple ceramic membranes was above 96%, as high as the BSA detection limit

Summary

Introduction

Trace organics such as pesticides, pharmaceuticals, personal care products and polymer additives are repeatedly found in surface- and groundwater sources (Ribeiro et al 2015). The number of these so-called micropollutants (MPs) has grown alarmingly in the last two decades, from < 100 to > 4000 (Tixier et al 2003). No relation between a consumption of specific MPs and human health problems has been reported yet (Darbre 2015; Christou et al 2017). The increasing amounts and numbers of MPs released into the environment are concerning, because their long-term effects on humans are unknown (Schwab et al 2005; Stuart et al 2012)

Methods

Results

Conclusion