Intensification of Red-G dye degradation used in the dyeing of alpaca wool by advanced oxidation processes assisted by hydrodynamic cavitation

Saponin Molecules from Quinoa Residues: Exploring Their Surfactant, Emulsifying, and Detergent Properties

The indiscriminate use of synthetic surfactants, despite their desirable properties, poses significant environmental risks to ecosystems. This study explores saponins extracted from quinoa (Chenopodium quinoa) residues as a sustainable alternative. Saponin extract (SE) with 42% purity, obtained through hydrodynamic cavitation and membrane technology, was analyzed to determine its techno-functional properties. The critical micelle concentration (CMC) was 1.2 g/L, reducing the surface tension (ST) from 72.0 mN/m to 50.0 mN/m. The effects of temperature (30-90 °C), pH (2-12), and salinity (10,000-150,000 ppm NaCl) on ST and the emulsification index (EI) were assessed using a Box-Behnken design. Optimized conditions yielded an ST of 49.02 mN/m and an EI of 63%. Given these characteristics, SE was evaluated as a detergent across diverse swatches. This study showcases the attributes of quinoa-derived saponins, highlighting their potential for eco-friendly detergent applications.

Sustainable approach for the treatment of dye-containing wastewater – a critical review

In the world’s rapidly expanding economy, textile industries are recognized as a substantial contributor to economic growth, but they are one of the most significant polluting industrial sectors. Dye-contaminated water sources can pose serious public health concerns, including toxicity, mutagenicity, and carcinogenicity among other adverse health effects. Despite a limited understanding of efficacious decolorization methodologies, the pursuit of a sustainable strategy for the treatment of a wide spectrum of dyes remains a formidable challenge. This article conducted an exhaustive review of extant literature pertaining to diverse physical, chemical, biological, and hybrid processes with the aim of ascertaining their efficacy. It also elucidates the advantages and disadvantages, cost considerations, as well as scalability impediments of the treatment methodologies, thereby facilitating the identification of optimal strategies for establishing techno-economically efficient processes in the sustainable handling of these effluents. The hybrid configuration exhibited superior efficiency and was documented to surmount the limitations and constraints inherent to individual techniques. The study also revealed that most of the proven and established dye removal techniques share a common limitation viz., the generation of secondary pollution (i.e., sludge generation, toxic intermediates, etc.) to the ecosystem.

Intensified degradation of tartrazine dye present in effluent using ultrasound combined with ultraviolet irradiation and oxidants

Effluent containing tartrazine can affect the environment and human health significantly prompting the current study into degradation using a sonochemical reactor operated individually and combined with advanced oxidation processes. The optimum conditions for ultrasound treatment were established as dye concentration of 10 ppm, pH of 3, temperature as 35 °C, and power as 90 W. The combination approach of H2O2/UV, H2O2/US, and H2O2/UV/US resulted in higher degradation of 25.44%, 57.4%, and 74.36% respectively. Use of ZnO/UV/US approach increased the degradation significantly to 85.31% whereas maximum degradation as 93.11% was obtained for the US/UV/Fenton combination. COD reduction was found maximum as 83.78% for the US/UV/Fenton combination. The kinetic analysis showed that tartrazine dye degradation follows pseudo first-order kinetics for all the studied processes. Combination of Fenton with UV and US was elucidated as the best approach for degradation of tartrazine.