Waste Algal Biomass as a Binder for Shaping Technical Adsorbents

Area of Science:

• Materials Science
• Biotechnology
• Chemical Engineering

Background:

• Traditional inorganic binders for alumina adsorbents require high sintering temperatures, increasing energy consumption and cost.
• Developing sustainable and effective binders from renewable resources is crucial for environmentally friendly industrial processes.

Purpose of the Study:

• To investigate the use of spray-dried biomass from genetically engineered *Chlamydomonas reinhardtii* as a binder for extruding alumina adsorbents.
• To evaluate the properties and performance of alumina adsorbents produced using algal biomass as a binder.

Main Methods:

• Algal biomass was spray-dried and used as a binder for alumina extrusion.
• Binder content and rheological properties (viscoelasticity coefficient, tan(δ)) were analyzed.
• Crush strength, water vapor adsorption capacity, and stability of the formed adsorbents were tested.

Main Results:

• Successful extrusion of alumina adsorbents was achieved with binder content above 15%.
• Algal biomass binder allowed for moderate processing temperatures (180 °C) and eliminated detectable transformed genes.
• The extrudates exhibited crush strengths >27 N, and adsorption capacity was 7.5 mol/kg.
• Adsorbent properties remained stable after immersion in solvents and multiple adsorption/desorption cycles.

Conclusions:

• Waste biomass from genetically engineered algae is a viable and effective binder for producing functional alumina adsorbents.
• This method offers a sustainable alternative to conventional binders, with moderate processing temperatures and good material performance.