flocculants production from wastewater

There are a few possibilities for allowances:
– The allowance for students is €200. The student can apply for ‘Wetsus Grant’ allowance (€200 extra; an internal committee decides if the allowance will be granted).
– Students can apply for Erasmus; (if the Erasmus grant is less than €400, the student can apply for the Wetsus Grant).
– Erasmus
*The Wetsus Grant allowance is not guaranteed and must be approved by the Grant Committee.


Fossil-based, potentially-toxic polymers such as polyacrylamide (PAM) are widely employed as flocculants in, for instance, drinking water production, (waste)water treatment, soil conditioners, microbial biomass harvesting. This is a still-growing global market in the order of several millions of tons per year. After application, a fraction of the flocculants end-up in the aquatic environment, raising serious environmental concerns since PAM degradation leads to acrylamide formation, which is neurotoxic, suspected carcinogenic and inhibits reproduction. Alternative, ‘greener’ polymeric flocculants are available (e.g. tannines, chitosan, alginate), but are not competitive with synthetic flocculants. A new biotechnological alternative to obtain competitive flocculants is through open-culture microbial conversion of waste(water) into extracellular polymeric substances (EPS), natural biopolymers excreted by microorganisms. These natural flocculants are biodegradable, do not pose environmental risks and have a lower carbon footprint than synthetic flocculants. Since they are produced from low-value residual streams, EPS can compete with current expensive flocculants while achieving both waste(water) treatment and recovery of valuable products.

        2. Research objective and hypothesis

Microbial EPS have been obtained from synthetic wastewater in lab-scale experiments at high yields. These EPS showed high potential for flocculation and heavy metal recovery in preliminary tests. The objective of this research is to produce EPS from synthetic and real wastewater. Bioreactor design and operating conditions will be optimized to maximize EPS production. We hypothesize that EPS will be produced at high efficiencies, displaying competitive flocculation performance in real-life conditions.

         3. Requirements

  • Background in Bioprocess Engineering/ Environmental Technology/ Chemical Engineering or equivalent;
  • Great interest in bioreactors, bioprocesses, biopolymers;
  • Good practical and experimental skills;
  • Experience with bioreactors, wastewater treatment;

    4. Duration and location
  • From 4 to 6 months;
  • Start: 01-06-2024.

How to apply:
Please attach your CV (max 2 pages) and motivation letter (max 1 page) in the application form below. You can contact the researcher Carlos Contreras questions through the message option below.

Application form: Microbial flocculants production from wastewater

  • Max. bestandsgrootte: 1 GB.
  • Max. bestandsgrootte: 1 GB.