Biochar imparted constructed wetlands (CWs) for enhanced biodegradation of organic and inorganic pollutants along with its limitation.

The remediation of polluted soil and water stands as a paramount task in safeguarding environmental sustainability and ensuring a dependable water source. Biochar, celebrated for its capacity to enhance soil quality, stimulate plant growth, and adsorb a wide spectrum of contaminants, including organic and inorganic pollutants, within constructed wetlands, emerges as a promising solution. This review article is dedicated to examining the effects of biochar amendments on the efficiency of wastewater purification within constructed wetlands. This comprehensive review entails an extensive investigation of biochar's feedstock selection, production processes, characterization methods, and its application within constructed wetlands. It also encompasses an exploration of the design criteria necessary for the integration of biochar into constructed wetland systems. Moreover, a comprehensive analysis of recent research findings pertains to the role of biochar-based wetlands in the removal of both organic and inorganic pollutants. The principal objectives of this review are to provide novel and thorough perspectives on the conceptualization and implementation of biochar-based constructed wetlands for the treatment of organic and inorganic pollutants. Additionally, it seeks to identify potential directions for future research and application while addressing prevailing gaps in knowledge and limitations. Furthermore, the study delves into the potential limitations and risks associated with employing biochar in environmental remediation. Nevertheless, it is crucial to highlight that there is a significant paucity of data regarding the influence of biochar on the efficiency of wastewater treatment in constructed wetlands, with particular regard to its impact on the removal of both organic and inorganic pollutants.

Exploring zeolite-based composites in adsorption and photocatalysis for toxic wastewater treatment: Preparation, mechanisms, and future perspectives.

Water scarcity has become a critical global concern exacerbated by population growth, globalization, and industrial expansion, resulting in the production of wastewater containing a wide array of contaminants. Tackling this challenge necessitates the adoption of innovative materials and technologies for effective wastewater treatment. This review article provides a comprehensive exploration of the preparation, applications, mechanisms, and economic environmental analysis of zeolite-based composites in wastewater treatment. Zeolite, renowned for its versatility and porous nature, is of paramount importance due to its exceptional properties, including high surface area, ion exchange capability, and adsorption capacity. Various synthetic methods for zeolite-based composites are discussed. The utilization of zeolites in wastewater treatment, particularly in adsorption and photocatalysis, is thoroughly investigated. The significance of zeolite in adsorption and its role in the photocatalytic degradation of pollutants are examined, along with its applications in treating volatile organic compounds (VOCs), dye wastewater, oil-field wastewater, and radioactive waste. Mechanisms underlying zeolite-based adsorption and photocatalysis, including physical and chemical adsorption, ion exchange, and surface modification, are elucidated. Additionally, the role of micropores in the adsorption process is explored. Furthermore, the review delves into regeneration and desorption studies of zeolite-based composites, crucial for sustainable wastewater treatment practices. Economic and environmental analyses are conducted to assess the feasibility and sustainability of employing zeolite-based composites in wastewater treatment applications. Future recommendations are provided to guide further research and development in the field of zeolite-based composites, aiming to enhance wastewater treatment efficiency and environmental sustainability. By exploring the latest advancements and insights into zeolite-based nanocomposites, this paper aims to contribute to the development of more efficient and sustainable wastewater treatment strategies. The integration of zeolite-based materials in wastewater treatment processes shows promise for mitigating water pollution and addressing water scarcity challenges, ultimately contributing to environmental preservation and public health protection.

Actas Pink-2B dye removal in biochar nanocomposites augmented vertical flow constructed wetland (VF-CWs).

Industries generate hazardous dye wastewater, posing significant threats to public health and the environment. Removing dyes before discharge is crucial. The ongoing study primarily focused on synthesizing, applying, and understanding the mechanism of green nano-biochar composites. These composites, including zinc oxide/biochar, copper oxide/biochar, magnesium oxide/biochar, and manganese oxide/biochar, are designed to effectively remove Actas Pink-2B (Direct Red-31) in conjunction with constructed wetlands. Constructed wetland maintained pH 6.0-7.9. At the 10th week, the copper oxide/biochar treatment demonstrated the highest removal efficiency of total suspended solids (72%), dissolved oxygen (7.2 mg/L), and total dissolved solids (79.90%), followed by other biochar composites. The maximum removal efficiency for chemical oxygen demand (COD) and color was observed at a retention time of 60 days. The electrical conductivity also followed the same order, with a decrease observed up to the 8th week before becoming constant. A comprehensive statistical analysis was conducted, encompassing various techniques including variance analysis, regression analysis, correlation analysis, and principal component analysis. The rate of color and COD removal followed a second-order and first-order kinetics, respectively. A significant negative relationship was observed between dissolved oxygen and COD. The study indicates that employing biochar composites in constructed wetlands improves textile dye removal efficiency.

The novelty of this study is the selection of Cymbopogon as a proper plant for phytoremediation of dye along with green metal oxide coated biochar. These were selected due to their good ability to remove organic pollutant. This study demonstrates the uptake and degradation processes of persistent dye in constructed wetland.

Utilization of ZnFe2O4-Polyaniline (PANI), ZnFe2O4-Polystyrene (PST), and ZnFe2O4-Polypyrrole (PPy) nanocomposites for removal of Red X-GRL and Direct Sky Blue dyes from wastewater: Equilibrium, kinetic and thermodynamic studies.

In this study, ZnFe2O4-Polyaniline (PANI), ZnFe2O4-Polystyrene (PST), and ZnFe2O4-Polypyrrole (Ppy) nanocomposites were synthesized by the adsorption method and characterized by field emission scanning electron microscopy and Fourier transform infrared spectrometer. Batch adsorption experiments were conducted for removing two types of hazardous dyes Red X-GRL and Direct Sky Blue 51 from an aqueous solution and the effect of pH, adsorbent dosage, contact time, and initial concentration of dyes were investigated. Meanwhile, kinetic, isotherm, and thermodynamic parameters were also determined. The electrolyte and surfactant effect was also tested for the prepared nanocomposites. To test the reusability desorption study was also conducted.

Green metal oxides coated biochar nanocomposites preparation and its utilization in vertical flow constructed wetlands for reactive dye removal: Performance and kinetics studies.

Major causes of water pollution in the ecosystem are pollutants such as dyes which are noxious. The present study was based on the synthesis of the green nano-biochar composites from cornstalk and green metal oxide resulting in Copper oxide/biochar, Zinc oxide /biochar, Magnesium oxide/biochar, Manganese oxide/biochar, biochar for removal of dyes combined with the constructed wetland (CW). Biochar Augmentation in constructed wetland systems has improved dye removal efficiency to 95% in order of copper oxide/biochar > Magnesium oxide/biochar > Zinc oxide/biochar > Manganese oxide/biochar > biochar > control (without biochar) respectively in wetlands. It has increased the efficiency of pH by maintaining pH 6.9-7.4, while Total Suspended Solids (TSS) removal efficiency and Dissolved oxygen (DO) increased with the hydraulic retention time of about 7 days for 10 weeks. Chemical oxygen demand (COD) and colour removal efficiency increased with the hydraulic retention time of 12 days for 2 months and there was a low removal efficiency for total dissolved solids (TDS) from control (10.11%) to Copper oxide /biochar (64.44%) and Electrical conductivity (EC) from control (8%) to Copper oxide /biochar (68%) with the hydraulic retention time of about 7 days for 10 weeks. Colour and chemical oxygen demand removal kinetics followed second and first-order kinetic. A significant growth in the plants were also observed. These results proposed the use of agricultural waste-based biochar as part of a constructed wetland substratum can provide enhanced removal of textile dyes. That can be reused.