Waste Cleaning Waste: Combining Alginate with Biowaste‐Derived Substances in Hydrogels and Films for Water Cleanup

Abstract

Biowaste‐derived substances isolated from green compost (BBS‐GC) are environmentally friendly reactants similar to humic substances, which contain multiple functionalities, that are suitable for adsorbing different kinds of pollutants in wastewater. Herein, sodium alginate (derived from brown algae) cross‐linked with both Ca2+ ions and BBS‐GC in the form of hydrogels and dried films are proposed as green, easy‐to‐form, and handleable materials for tertiary water treatments. The results show that both hydrogels and films are mechanically stable and can effectively remove differently charged dyes through an adsorption mechanism that can be described by the Freundlich model. BBS‐GC‐containing gels always performed better than samples prepared without BBS‐GC, revealing that such unconventional materials can integrate waste valorization and water decontamination, potentially providing social and environmental benefits.

Insights into performances of magnetic and bio-based doped-nanohydroxyapatites as water decontamination agents

“…Crystal Violet (cationic), instead, was captured, but only by nAp-Fe-BBS powder (Figure 6a), reaching the 60% adsorption level in 1 hour and thus confirming the affinity of this dye with BBS. 16,23,62 Qmax was estimated through isotherm fitting with the Langmuir model (R 2 =0.92) as 52 mg g -1 (see Figure 6b), which is in line with the average results of other hydroxyapatite-based systems and, in general, other materials already described in the literature. [63][64][65][66] In the tested conditions, the CV desorption was limited to 1-2%.…”

Soybean peroxidase immobilised on cellulose-alginate hydrogels for removal of recalcitrant organic pollutants in water

“…A typical hydrogels' property is water uptake, 32,41 depending on their structure. Therefore, different behaviour of synthesized hydrogels was investigated using the gravimetric method described in section 2.4.…”

“…2B, it is also possible to note bundles of fibres that are not completely separated, probably due to the residual lignin and hemicellulose not totally removed during the extraction process (irrelevant in the functionalisation reaction). A typical hydrogels' property is water uptake 32,41 , depending on their structure. Therefore, different behaviour of synthesized hydrogels was investigated using the gravimetric method described in section 2.4.…”