Applications of Biocatalysts for Sustainable Oxidation of Phenolic Pollutants: A Review

Adsorption Behaviors and Mechanism of Phenol and Catechol in Wastewater by Magnetic Graphene Oxides: A Comprehensive Study Based on Adsorption Experiments, Mathematical Models, and Molecular Simulations

This study provides a comprehensive analysis of the adsorption behaviors and mechanisms of phenol and catechol on magnetic graphene oxide (MGO) nanocomposites based on adsorption experiments, mathematical models, and molecular simulations. Through systematic experiments, the influence of various parameters, including contact time, pH conditions, and ionic strength, on the adsorption efficacy was comprehensively evaluated. The optimal contact time for adsorption was identified as 60 min, with the observation that an increase in inorganic salt concentration adversely affected the MGOs' adsorption capacity for both phenol and catechol. Specifically, MGOs exhibited a superior adsorption performance under mildly acidic conditions. The adsorption isotherm was well represented by the Langmuir model, suggesting monolayer coverage and finite adsorption sites for both pollutants. In terms of adsorption kinetics, a pseudo-first-order kinetic model was the most suitable for describing phenol adsorption, while catechol adsorption conformed more closely to a pseudo-second-order model, indicating distinct adsorption processes for these two similar compounds. Furthermore, this research utilized quantum chemical calculations to decipher the interaction mechanisms at the molecular level. Such calculations provided both a visual representation and a quantitative analysis of the interactions, elucidating the underlying physical and chemical forces governing the adsorption phenomena. The findings could not only offer crucial insights for the treatment of coal industrial wastewater containing phenolic compounds with bridging macroscopic observations with microscopic theoretical explanations but also advance the understanding of material-pollutant interactions in aqueous environments.

Electrochemical Sensors Based on Transition Metal Materials for Phenolic Compound Detection

Electrochemical sensors have been recognized as crucial tools for monitoring comprehensive chemical information, especially in the detection of a significant class of molecules known as phenolic compounds. These compounds can be present in water as hazardous analytes and trace contaminants, as well as in living organisms where they regulate their metabolism. The sensitive detection of phenolic compounds requires highly efficient and cost-effective electrocatalysts to enable the development of high-performance sensors. Therefore, this review focuses on the development of advanced materials with excellent catalytic activity as alternative electrocatalysts to conventional ones, with a specific emphasis on transition metal-based electrocatalysts for the detection of phenolic compounds. This research is particularly relevant in diverse sectors such as water quality, food safety, and healthcare.

A review on waste valorization, biotechnological utilization, and management of potato

One of the most popular, cost-effective crops that are consumed globally is the potato. Due to the expanding food crisis, there is an increase in the demand for potato-based agro-food items. At the same time, it is noted that this pathway of ecological pollution from large-scale wastes is challenging to manage. The food sector generates a lot of waste, which can be controlled better via biotechnological methods. The potato industry is one of the industries that generate a large amount of garbage that is harmful to the environment. Several by-products of industrial potato production, such as potato peels (PPs), starch, flakes, and granules, are disposed of despite being rich sources of nutrients and bioactive ingredients. These wastes can subsequently be used in biotechnological processing to produce microbial polysaccharides, yeast cellular biomass, lipids, protein, enzymes, organic acids, and carotenoids as components of the microbial medium. Similarly, food processing based on potatoes uses a lot of water, which is an issue because it pollutes wastewater. The most popular method for reducing trash that is both affordable and environmentally beneficial at the moment is biotechnology. The purpose of this review study is to illustrate the potential of applying biotechnological techniques to tackle the potato waste problem while simultaneously enhancing the economy. By discussing recent breakthroughs as well as current flaws in this method of controlling potato trash, this paper seeks to give a future vision of the justifiable use of biotechnological-based potato waste management and utilization strategies.

The concentrated polyaluminum chloride with tailor-made distribution of Al species: synthesis, distribution and transformation of Al species, and coagulation performance

Production of concentrated polyaluminum chloride (PACl) with the proper distribution of Al species (Ala, Alb, and Alc) is still a challenging issue on both industrial and laboratory scale. Hence, the effects of total aluminum concentration (AlT) at high levels, regular basicity values, and low base injection rates on the distribution of Al species in PACl solutions were investigated using quadratic models. The results confirmed the possibility to synthesize tailor-made PACl solutions with a specified value of either Ala, Alb, or Alc within the range of 22-51%, 4-51%, or 0.5-74%, respectively. For instance, in agreement with the predicted value, a PACl sample rich in both Alb (42,200 ppm) and AlT was produced by applying the basicity of 1.7, AlT of 9.07% as Al2O3, and basification rate of 0.48 ml/h. In addition, the maximum Alc could be acquired by exploiting the highest C, B, and Q values. This condition also minimized both Ala and Alb. The trends of Ala and Alc changes by the increment of basicity were concave and convex, respectively, while Alb showed either a decreasing trend or a concave pattern based on the values of injection rate and AlT. The Alb-rich PACl sample was effectively applied for turbidity removal from synthetic wastewater at various pHs and initial turbidities. At best, residual turbidity of about 1% was observed after the coagulation process. These findings can be constructive for the production and application of tailor-made PACl.

Colorimetric sensing strategy for detection of cysteine, phenol cysteine, and phenol based on synergistic doping of multiple heteroatoms into sponge-like Fe/NPC nanozymes

Nanozymes have both the high catalytic activity of natural enzymes and the stability and economy of mimetic enzymes. Research on nanozymes is rapidly emerging, and the continuous development of highly catalytic active nanozymes is of far-reaching significance. This work reports heteroatomic nitrogen (N) and phosphorus (P) double-doped mesoporous carbon structures and metallic Fe coordination generated sponge-like nanozymes (Fe/NPCs) with good peroxidase activity. On this basis, we constructed a highly sensitive colorimetric sensor with cysteine and phenol as simulated analytes using Fe/NPCs nanozymes, and the response limits reached 53.6 nM and 5.4 nM, respectively. Besides, the method has high accuracy in the detection of cysteine and phenol at low concentrations in serum and tap water, which lays a foundation for application in the fields of environmental protection and biosensors.