UV-activated persulfates oxidation of anthraquinone dye: Kinetics and ecotoxicological assessment.

Sulfate radical-based advanced oxidation processes (SR-AOPs) are gaining popularity as a feasible alternative for removing recalcitrant pollutants in an aqueous environment. Persulfates, namely peroxydisulfate (PDS) and peroxymonosulfate (PMS) are the most common sulfate radical donors. Persulfates activation by ultraviolet (UV) irradiation is considered feasible due to the high concentration of radicals produced as well as the lack of catalysts leaching. The research focuses on determining the impact of activated PDS and PMS on the degradation of anthraquinone dye, i.e., Acid Blue 129 (AB129). UV-activated PDS and PMS can quickly degrade the AB129 as well as restrict the formation of by-products. This could explain the reduced ecotoxicity levels of the treated water after degradation, using an aquatic plant (Lemna minor) and a crustacean (Daphnia magna). This, on the other hand, can ensure that the sulfate radical-based processes can be an environmentally friendly technology.

Gum Hydrocolloids Reinforced Silver Nanoparticle Sponge for Catalytic Degradation of Water Pollutants.

The accumulation of organic contaminants including dyes in aquatic systems is of significant environmental concern, necessitating the development of affordable and sustainable materials for the treatment/elimination of these hazardous pollutants. Here, a green synthesis strategy has been used to develop a self-assembled gum kondagogu-sodium alginate bioconjugate sponge adorned with silver nanoparticles, for the first time. The properties of the nanocomposite sponge were then analyzed using FTIR, TGA, SEM, and MicroCT. The ensued biobased sponge exhibited hierarchical microstructure, open cellular pores, good shape memory, and mechanical properties. It merges the attributes of an open cellular porous structure with metal nanoparticles and are envisaged to be deployed as a sustainable catalytic system for reducing contaminants in the aqueous environment. This nanocomposite sponge showed enhanced catalytic effectiveness (km values up to 37 min-1 g-1 and 44 min-1 g-1 for methylene blue and 4-nitrophenol, respectively), antibacterial properties, reusability, and biodegradability (65% biodegradation in 28 days).

Biomacromolecule assembly based on gum kondagogu-sodium alginate composites and their expediency in flexible packaging films.

The assembly of bio-based macromolecules of gum kondagogu/sodium alginate (KO/SA) was fabricated using glycerol as a plasticiser and their optimum blending ratio was identified based on their physical and chemical, structural, mechanical, barrier, and morphological properties. The attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis show that both biomacromolecules are well organised due to the hydrogen bond interaction between molecular chains involving the hydroxyl, carbonyl, and acetyl groups. Structural identification was performed by recording X-ray diffraction (XRD) spectra. Field emission scanning electron microscopy (FESEM) was used to identify the distinction between the surface of the films of biopolymers, and their conjugates, where the addition of SA increased the surface homogeneity and smoothness. The water contact angle of the blend films reached up to 81°, although the value for pure biomacromolecule films was very low. The blend films also exhibited high tensile strength (up to 24 MPa) compared to the pure biopolymer films. Investigation of film-forming ability, mechanical strength, permeability, transparency, and biodegradability of the developed KO/SA bio-macromolecular association may be established as green and sustainable food packaging films.

Gum Kondagogu/Reduced Graphene Oxide Framed Platinum Nanoparticles and Their Catalytic Role.

This study investigates an environmentally benign approach to generate platinum nanoparticles (Pt NP) supported on the reduced graphene oxide (RGO) by non-edible gum waste of gum kondagogu (GK). The reaction adheres to the green chemistry approach by using an aqueous medium and a nontoxic natural reductant-GK-whose abundant hydroxyl groups facilitate in the reduction process of platinum salt and helps as well in the homogenous distribution of ensued Pt NP on RGO sheets. Scanning Electron Microscopy (SEM) confirmed the formation of kondagogu gum/reduced graphene oxide framed spherical platinum nanoparticles (RGO-Pt) with an average particle size of 3.3 ± 0.6 nm, as affirmed by Transmission Electron Microscopy (TEM). X-ray Diffraction (XRD) results indicated that the Pt NPs formed are crystalline with a face-centered cubic structure, while morphological analysis by XRD and Raman spectroscopy revealed a simultaneous reduction of GO and Pt. The hydrogenation of 4-nitrophenol could be accomplished in the superior catalytic performance of RGO-Pt. The current strategy emphasizes a simple, fast and environmentally benign technique to generate low-cost gum waste supported nanoparticles with a commendable catalytic activity that can be exploited in environmental applications.