(Leader: E. Cuevas; C. Cabrera, Z. Chen, Liz Diaz-Vázquez, E. Nicolau, J.R. Ortiz, K. Soto-Hidalgo)
This IRG will work in the development of nanomaterials for water purification, soil remediation, and resource recovery. In particular, reactive membranes for water purification, heavy metal remediation, and microbial reactors.
Subproject 1: Nano zero valent iron, core-shell-Fe0/FexOy nanoparticles, for remediation heavy metals in wetland soil and its reusability for energy applications.
The main goal of this subproject is to understand the behavior of the interaction of plants and nZVI for in situ applications in contaminated wetlands soils, a process known as phytonanoremediation.
The subproject will consist of three parts:
1) eco- hydrologic assessment of the wetland
2) bioprospecting of heavy metals in the plant/soil/groundwater matrix
3) establishment of in situ experiments combining the plant/soil/groundwater matrix with nZVI.
The in-situ phyto/nanoremediation experiments will be carried out as follows: nZVI nanoparticles will be placed in the four cardinal spots near the plant species chosen for the studies, between 5-10 cm depth where fine roots are located. Five plants of each species will be used for the research. nZVI nanoparticles will also be placed at the same substrate depth in five 100 cm2 plant-free plots in each stand.
Subproject 2: Development of pH switchable polymer nanofibers for the recovery of polyphenolic compounds.
The occurrence of polyphenolic compounds such as tannic acid, gallic acid, catechol and others in is common in wetlands like Las Cucharillas.
Polyphenols in general can find a wide variety of applications ranging from the production of plastics and resins to adhesives.
The main goal of this sub-project is to recover polyphenols from the wetland to further prepare membranes and adhesives that could be useful for the remediation of the site itself.
In order to accomplish the overall goal of this subproject we will evaluate the use of polymer-nanocellulose hydrogels as pH switchable adsorbents of polyphenolic compounds.
Subproject 3: A synergistic combination of algal wastewater treatment, hydrothermal biofuel production and fabrication of algal base nanomaterials.
The long-term goal of this subproject is test the suitability of a novel environmental friendly system for algal biofuel production that can improve simultaneously conventional wastewater treatment by nutrient removal and generation of high yields of biofuel and co-products that are useful in the synthesis of nanomaterials.
The physical and chemical methods used for the generation of nanomaterials have various drawbacks such as high cost of production, requiring, high energy input and generation of toxic byproducts. To overcome these limitations, several bio-synthesis methods have been reported. Here we propose the use of wetland substrate leaching as a substrate for algal cultivation for the biosynthesis of nanomaterials as a cost effective, nontoxic, and ecofriendly alternative to traditional methods.
The alginate, carrageenan or ulvan from macroalgae will be used to generate nanopolysacharides that could be used in IRG 1 subproject 2 for the fabrication of functional membranes for water purification or for energy conversion devices.
After the extraction of algae bioproducts the resulting biomass residue will be submitted to the HTL process, where four byproducts will be obtained, wastewater (rich in nutrients could be reuse as algae fertilizer), bio-oil, biochar (could be activated and modified and used as catalyst support or in electrode fabrication) and a gas phase rich in CO2 and methane.
In addition, since algae are being easily grown under laboratory conditions and sensitive to a wide array of both inorganic and organic chemical, they will be useful for the study of ecotoxicology of CIRE2N-generated nanomaterials.