Research projects
1. Bioaugmentation treatment approaches using encapsulated microorganisms
Bioaugmentation, defined as the strategic addition of cultured microorganisms to expedite contaminant degradation, emerges as a cost-effective and environmentally sustainable approach in wastewater treatment. Our current research endeavors focus on the innovative Small Bioreactor Platform (SBP) technology, developed in partnership with Biocastle, an Israeli start-up (https://www.bio-castle.com). This cutting-edge technology is centered around a uniquely designed capsule that effectively isolates an introduced microbial culture within it, thereby preventing interaction with the native microbial flora in the surrounding wastewater. The primary objective of this technology is to enhance microbial diversity within the wastewater system, facilitating the targeted removal of specific contaminants and improving the overall stability of the biological processes involved in wastewater treatment.
This approach has shown promise in the selective elimination of various organic substances and nitrogenous compounds. Wastewater is treated as it flows through bioreactors containing these specialized, encapsulated bacterial cultures. Our recent projects encompass a diverse array of applications, including the treatment of dairy industry effluents, and wastewater with high concentrations of phenolic compounds, nitrogen compounds, and micropollutants.
2. Removal of micropollutants from water
Many studies have demonstrated that endocrine disrupting compounds (EDCs) can mimic hormones or interfere with the action of endogenous hormones. Due to their high bioactivity, ubiquitous nature, toxicity and persistence, it is extremely important to develop novel approaches for elimination of these compounds from the environment. I am also collaborating with researchers from other fields (chemical and physical treatments) in order to combine the biological approach with physico-chemical treatments such as advanced oxidation processes (AOP) (UV, ozone, photocatalysis) for accelerating the breakdown of micro-pollutants and industrial organic pollutants.
The aim of this study is to use bioaugmentation approaches for accelerating the biodegradation rates of phenolic compounds (which are toxic for most bacteria) in olive mill wastewater. This is done using cultures previously isolated from an olive mill wastewater treatment bioreactor.
3. Treatment of phenols in olive mill wastewater
4. Removal of phosphorus from sewage effluents using clays
Adsorption is gaining interest as an effective advanced method for treatment of treated sewage (effluents) with a high phosphorus (P) content. In the Golan Heights, 80% of the sewage is from dairy farms, and only 20% from humans. This results in treated effluents that are rich in P, which may increase the risk for eutrophication (algal bloom) in natural streams and in Lake Kinneret when these effluents are used for irrigation.
This research focuses on improving the quality of effluents used for agricultural irrigation by P removal using a novel lanthanum-modified bentonite clay (Phoslock®) and local natural clays. The P-saturated clays will also be tested for the phytoavailability of the adsorbed P for use as an agricultural fertilizer.
5. Advanced oxidation processes for water treatment
Discharge of conventionally treated wastewater results in release of micropollutants (e.g., pharmaceuticals, hormones, pesticides) into the environment, including small streams, rivers, lakes, and the marine environment. They also reach soil and groundwater during water reclamation for irrigation, and they are adsorbed into crops. In Israel, around 80% of the effluents are reused for irrigation in agriculture. In consequence, an adequate treatment in order to remove these micropollutants should be applied. In our research, different oxidation techniques are used such as direct photolysis, UV-H2O2, UV-persulfate for removal of micropollutants from water and effluents.
6. Nanotechnology for removal of micropollutants in water
This research explores the potential of nanotechnology in water purification processes. The unique high surface area of nanoparticles facilitates their role as efficient carriers for various oxidant species, significantly improving the effectiveness of water treatment methods. A notable aspect of this study is the incorporation of magnetic cores within these nanocomposites. This innovative approach enables the repeated utilization of the nanocomposites by facilitating their retrieval and reuse through the application of a magnetic field. Our research primarily focuses on synthesizing diverse types of nanocomposites, specifically tailored for the oxidation of micropollutants in water. We also extensively evaluate their reusability across multiple cycles, aiming to establish their efficacy and practicality for implementation in pilot-scale water treatment facilities.
7. Characterization and application of antimicrobial compounds in microalgae and fungi against microorganisms
The search for novel compounds of algal origin has increased in the last decades for their application in various areas such as pharmaceutical, human or animal nutrition, cosmetics or bioenergy. In this context of blue technology development, microalgae are of particular interest due to their immense biodiversity and their relatively simple growth needs. In this progect, we investigate the promising use of microalgae and microalgal compounds as sources of natural antibiotics against human pathogens and phytopathogens. An alternative to conventional antibiotics is needed as the microbial resistance to these drugs is increasing in humans, plants and animals. Furthermore, using natural antibiotics could meet the consumer demand to avoid chemicals in food, would support a sustainable aquaculture and present the advantage of being environmentally friendly. Using natural and renewable microalgal compounds is still in its early days, but considering the important research development and rapid improvement in culture, extraction and purification processes, the valorization of microalgae will surely extend in the future.
8. Circular economy of waste: Reuse of agricultural waste for drinking water treatment.
The overall aim of this research is to test the scientific and technical feasibility of the reuse of agricultural waste as biochar for its application in water treatment. The functional groups in activated carbon will activate persulfate to generate sulfate radicals and hydroxyl radicals, which are responsible for the oxidation of micropollutants such as disinfection by-products (DBPs). These radicals are transformed into sulfate and hydroxyl anions which are not harmful to the environment. The destructive and non-selective characteristics of the oxidation process make it a highly advantageous treatment for the degradation of different DBPs. Furthermore, the high surface area as well as functionalization of the biochar will allow the adsorption of organics and DBPs.
