Hydrothermally Synthesized rGO/MnO2/MoS2 Nanohybrids as Superior Bifunctional Electrocatalysts for Oxygen and Hydrogen Evolution Reactions.

This investigation delved into the field of bifunctional electrocatalyst water splitting, aimed at advancing sustainable energy by addressing the scarcity of efficient nonprecious electrocatalysts capable of facilitating both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). This study focused on nanohybrids consisting of hydrothermally synthesized rGO/MnO2/MoS2 composites and highlighted their efficacy as bifunctional electrocatalysts. The synergistic integration of rGO/MnO2/MoS2 enhanced the surface area, magnified electroactive sites, established a customized conductive arrangement, and provoked the efficiency in splitting of water. The nanohybrid displayed exceptional catalytic performance for the OER and HER, with significantly reduced overpotentials of 208 and 205 mV in 1 M KOH at 10 mA cm-2 current density, respectively. The findings underscore the potential of these cost-effective and environmentally friendly rGO/MnO2/MoS2 nanohybrids in advancing the field of electrocatalysis for renewable energy applications.

A review on recent advancements in the treatment of polyaromatic hydrocarbons (PAHs) using sulfate radicals based advanced oxidation process.

Polyaromatic hydrocarbons (PAHs) are the most persistent compounds that get contaminated in the soil and water. Nearly 16 PAHs was considered to be a very toxic according US protection Agency. Though its concentration level is low in the environments but the effects due to it, is enormous. Advanced Oxidation Process (AOP) is an emergent methodology towards treating such pollutants with low and high molecular weight of complex substances. In this study, sulfate radical (SO4‾•) based AOP is emphasized for purging PAH from different sources. This review essentially concentrated on the mechanism of SO4‾• for the remediation of pollutants from different sources and the effects caused due to these pollutants in the environment was reduced by this mechanism is revealed in this review. It also talks about the SO4‾• precursors like Peroxymonosulfate (PMS) and Persulfate (PS) and their active participation in treating the different sources of toxic pollutants. Though PS and PMS is used for removing different contaminants, the degradation of PAH due to SO4‾• was presented particularly. The hydroxyl radical (•OH) mechanism-based methods are also emphasized in this review along with their limitations. In addition to that, different activation methods of PS and PMS were discussed which highlighted the performance of transition metals in activation. Also this review opened up about the degradation efficiency of contaminants, which was mostly higher than 90% where transition metals were used for activation. Especially, on usage of nanoparticles even 100% of degradation could be able to achieve was clearly showed in this literature study. This study mainly proposed the treatment of PAH present in the soil and water using SO4‾• with different activation methodologies. Particularly, it emphasized about the importance of treating the PAH to overcome the risk associated with the environment and humans due to its contamination.

Effective removal of chromium by adsorption using Delonix regia bark derived activated carbon from aqueous solution: a sustainable approach.

This study introduces a new biosorbent derived from Delonix regia bark-activated carbon to efficiently remove Chromium Cr(VI) metal ions from aqueous systems. The biosorbent was synthesized from the bark powder of the plant species and chemically activated with phosphoric acid. The biosorbent was characterized using FTIR, SEM, and BET to determine its functional properties and structural morphology. The batch adsorption experiments examined the optimal conditions for Cr(VI) metal ion adsorption, identifying that the highest removal efficiency occurred at pH levels of 2. The ideal adsorbent dosage was determined to be 2.5 g/L, with equilibrium achieved at a contact time of 60 min at the optimal temperature of about 303 K for a Cr(VI) metal ion concentration of 20 mg/L. Various isotherm models were applied to the adsorption equilibrium values, revealing that the adsorbent had a maximum removal capacity of approximately 224.8 mg/g for Cr(VI) metal ions. The adsorption process of Cr(VI) on the DAC biosorbent was best described by the Freundlich isotherm, indicating multilayer adsorption. The kinetic data fit well with the pseudo-second-order model. Thermodynamic parameters suggested that the adsorption process was spontaneous, exothermic, and feasible across different temperatures. Furthermore, the desorption studies showed that the DAC biosorbent can easily be rejuvenated and utilized several cycles with high adsorption capacity. These findings indicate that the developed adsorbent is environmentally friendly and effective for removing Cr(VI) from water systems.

A critical review on recent research progress on microplastic pollutants in drinking water.

Plastic pollution is an emerging issue in recent days. Persistent plastic particles reach the atmosphere, land and water by multiple pathways. Research has confirmed that the existence of plastic particles is found surprisingly everywhere, from the Artic to the Antarctic region. The probability of ingestion of plastic by all living forms is quite natural, as the whole planet's environment is polluted with microplastic particles. The bioaccumulation of microplastics is a threat and the consequences for living beings are yet to be explored. Microplastics present in different drinking water sources like rivers, lakes, treatment units etc. are studied by several researchers, covering various aspects. Research carried out by various scientists on the microplastics in different drinking water sources is highlighted in this review. In view of the previous research carried out on various aspects of microplastic particles, the necessity of a uniform protocol for qualitative and quantitative analysis of microplastic is ascertained. Microplastic pollution is an ongoing environmental concern, it must be addressed and research should be expanded.

Electrodeionization: Principle, techniques and factors influencing its performance.

Ecosystems are becoming more and more polluted, hence sustainable techniques of pollution removal are needed. In the recent times, exceedingly pure water has become ideal for several industries. Modern industry needs ultra-pure water, which is highly processed water that is devoid of colloidal particles and has a conductivity of less than 0.06 µS. A very effective method for removing ionic chemicals from polluted waters emerged recently called electrodeionization. Continuous electrodeionization (CEDI) is a technique for producing high-purity water. Besides rendering purified water, the technique has got promising wastewater treatment technologies - by facilitating the eradication of ionizable compounds, hazardous chemicals, radioactive pollutants, heavy metals and other potential contaminants. Innovative materials have been developed in order to advance and improve this technique, which would result in enormous ecological and financial benefit on a worldwide scale. In this review article, several factors that affect the performance of CEDI has been comprehended, with the impact of Ion-exchange resins and membranes as the focal point.

Biodegradation of oil-contaminated aqueous ecosystem using an immobilized fungi biomass and kinetic study.

Remediation of environmental oil pollution with the usage of fungal organisms has proven to be a successful cleanup bioremediation method for organic contaminants. To investigate the breakdown of oil pollutants in water environments, biosurfactant-producing fungi have been isolated from oil-polluted soil samples. 16s rRNA sequencing technique was performed to identify the fungal organism and phylogenetic tree has been constructed. A variety of biosurfactant screening tests have demonstrated the better biosurfactant producing ability of fungi. The emulsion's stability, which is essential for the biodegradation process, was indicated by the emulsification index of 68.48% and emulsification activity of 1.3. In the isolated biosurfactant, important functional groups such as amino groups, lipids, and sugars were found according to thin layer chromatography analysis with a maximum retention value of 0.85. A maximum oil degradation of around 64% was observed with immobilized beads within 12 days. The half-life, and degradation removal rate constant of 20.21 days and 0.03 day-1, respectively, have been determined by the degradation kinetic analysis. GCMS analysis confirmed the highly degraded hydrocarbons such as nonanoic acid and pyrrolidine. The immobilized fungi exhibit better oil biodegradability in aqueous solutions.

Rhizobium mayense sp. Nov., an efficient plant growth-promoting nitrogen-fixing bacteria isolated from rhizosphere soil.

The nitrogen-fixing bacterium has great prospects in replacing synthetic fertilizers with biofertilizers for plant growth. It would be a useful tool in eradicating chemical fertilizers from use. Five nitrogen-fixing bacteria were isolated from the Tea and Groundnut rhizosphere soil out of which RSKVG 02 proved to be the best. The optimized condition of RSKVG 02 was found to be pH 7 at 30 °C utilizing 1% glucose and 0.05% ammonium sulfate as the sole carbon and nitrogen source. Plant growth-promoting traits such as IAA and ammonia were estimated to be 82.97 ± 0.01254a µg/ml and 80.49 ± 0.23699a mg/ml respectively. Additionally, their phosphate and potassium solubilization efficiency were evaluated to be 46.69 ± 0.00125 b mg/ml and 50.29 ± 0.000266 mg/ml. Morphological, and biochemical methods characterized the isolated bacterial culture, and molecularly identified by 16 S rRNA sequencing as Rhizobium mayense. The isolate was further tested for its effects on the growth of Finger millet (Eleusine coracana) and Green gram (Vigna radiata) under pot conditions. The pot study experiments indicated that the bacterial isolates used as bio inoculants increased the total plant growth compared to the control and their dry weight showed similar results. The chlorophyll content of Green gram and Finger millet was estimated to be 19.54 ± 0.2784a mg/L and 15.3 ± 0.0035 mg/L which suggested that Rhizobium sp. Possesses high nitrogenase activity. The enzyme activity proved to use this bacterium as a biofertilizer property to enhance soil fertility, efficient farming, and an alternative chemical fertilizer. Therefore, Rhizobium mayense can be potentially used as an efficient biofertilizer for crop production and increase yield and soil fertility.

Experimental investigation of the electrochemical detection of sulfamethoxazole using copper oxide-MoS2 modified glassy carbon electrodes.

An electrochemical sensor detection of sulfamethoxazole was performed using a copper oxide Molybdenum sulfide modified glassy carbon electrode using Molybdenum sulfide (CuO/MoS2) functionalization. As part of the characterization process, materials were characterized via cyclic voltammetry (CV), Square wave voltammetry (SWV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). To optimize the performance of the experiment, parameters like the scan rate and pH, the electrolytes study, the stability, the comparative study and repeatability were optimized. In comparison to CuO, MoS2 and bare Glassy carbon electrode (GCE), an electrochemical sensor that incorporated CuO/MoS2 exhibited exceptional electrochemical performance. CuO/MoS2 modified electrodes showed a higher peak current for oxidation compared with bare, CuO and MoS2 modified electrodes, which demonstrated enhanced electrochemical conductivity for detection of SMX by minimizing oxidation potential from +0.18 V to +0.10 V. In the range of 100-800 µl SMX concentrations, the peak current linearly correlated with the concentration of SMX. In the calibration plot, the modified electrode showed linearity under ideal circumstances for SMX concentrations starting at 0.3 µM. This study investigated the presence of SMX with a detection limit of 0.34 Pg/L. CuO/MoS2 based electrochemical sensor, according to our analysis, are potentially useful in applications requiring the detection of trace amounts of SMX.

Mixed polyaromatic hydrocarbon degradation by halotolerant bacterial strains from marine environment and its metabolic pathway.

Accidents involving diesel oil spills are prevalent in sea- and coastal regions. Polycyclic aromatic hydrocarbons (PAHs) can be adsorbed in soil and constitute a persistent contaminant due to their poor water solubility and complex breakdown. PAHs pollution is a pervasive environmental concern that poses serious risks to human life and ecosystems. Thus, it is the need of the hour to degrade and decontaminate the toxic pollutant to save the environment. Among all the available techniques, microbial degradation of the PAHs is proving to be greatly beneficial and effective. Bioremediation overcomes the drawbacks of most physicochemical procedures by eliminating numerous organic pollutants at a lower cost in ambient circumstances and has therefore become a prominent remedial option for pollutant removal, including PAHs. In the present study, we have studied the degradation of Low molecular Weight and High Molecular Weight PAH in combination by bacterial strains isolated from a marine environment. Optimum pH, temperature, carbon, and nitrogen sources, NaCl concentrations were found for efficient degradation using the isolated bacterial strains. At 250 mg/L concentration of the PAH mixture an 89.5% degradation was observed. Vibrio algiolytcus strains were found to be potent halotolerant bacteria to degrade complex PAH into less toxic simple molecules. GC-MS and FTIR data were used to probe the pathway of degradation of PAH.

Application of Salvinia sps. in remediation of reactive mixed azo dyes and Cr (VI) - Its pathway elucidation.

The emerging industrialization has resulted in the rapid growth of textile industries across the globe. The presence of xenobiotic pollutants in textile wastewater threatens the ecosystem. Applying different microbes (bacteria, fungi & algae) has paved the way for phytoremediation - the eco-friendly, cost-effective method. The present study focuses on the phytoremediation of reactive dyes - Reactive red, Reactive Brown & Reactive Black and Cr (VI) in synthetic textile wastewater using Salvinia sps. The mixed azo dyes of each 100 mg/L showed decolourization of 75 ± 0.5% and 82 ± 0.5% of removal of 20 mg/L of Cr (VI) after eight days of incubation in a phytoreactor setup. Chlorophyll analysis revealed the gradual decrease in the photosynthetic pigments during the remediation. The degraded metabolites were analyzed using FT-IR and showed the presence of aromatic amines on day zero, which were converted to aliphatic amines on day four. The GC-MS analysis revealed the disruption of -NN- bond, rupture of -CN- bond, scission of -N-N-bond, and loss of -SO3H from the Reactive Black dye leading to the formation of an intermediate p-Hydroxy phenylhydrazinyl. The rupture of Reactive red dye resulted in the formation of p-Hydrazinyl toluene sulphonic acid, Naphthyl amine -3,6-disulphonic acid and 8-Hydroxy Naphthyl amine -3,6-disulphonic acid. Decarboxylation, desulphonation, deoxygenation and deamination of Reactive Brown dye showed the presence of different metabolites and metabolic pathways were proposed for the reactive azo dyes which were phytoremediated.

Acetylcholinesterase biosensors for electrochemical detection of neurotoxic pesticides and acetylcholine neurotransmitter: A literature review.

Neurotoxic pesticides are a group of chemicals that pose a severe threat to both human health and the environment. These molecules are also known to accumulate in the food chain and persist in the environment, which can lead to long-term exposure and adverse effects on non-target organisms. The detrimental effects of these pesticides on neurotransmitter levels and function can lead to a range of neurological and behavioral symptoms, which are closely associated with neurodegenerative diseases. Hence, the accurate and reliable detection of these neurotoxic pesticides and associated neurotransmitters is essential for clinical applications, such as diagnosis and treatment. Over the past few decades, acetylcholinesterase (AchE) biosensors have emerged as a sensitive and reliable tool for the electrochemical detection of neurotoxic pesticides and acetylcholine. These biosensors can be tailored to utilize the high specificity and sensitivity of AchE, enabling the detection of these chemicals. Additionally, enzyme immobilization and the incorporation of nanoparticles have further improved the detection capabilities of these biosensors. AchE biosensors have shown tremendous potential in various fields, including environmental monitoring, clinical diagnosis, and pesticide residue analysis. This review summarizes the advancements in AchE biosensors for electrochemical detection of neurotoxic pesticides and acetylcholine over the past two decades.

Enhancement of antifouling properties, metal ions and protein separation of poly(ether-ether-sulfone) ultrafiltration membranes by incorporation of poly ethylene glycol and n-ZnO.

Composite polymeric membranes with enhanced anti-fouling properties, antimicrobial activities and flux were produced via the phase inversion technique using poly (ether-ether-sulfone) (PEES)/polyethylene glycol (PEG) and n-ZnO. SEM and ATR-FTIR spectroscopy were used to study the morphological and chemical properties of the resulting ultrafiltration membranes. PEG and n-ZnO concentration has an effect on membrane morphologies, ultrafiltration performance, thermal characteristics, metal ion separation studies, surface hydrophilicity and anti-fouling capabilities. The permeate flux increased when the PEG concentration was raised. This results revealed that adding PEG and n-ZnO to membranes increased their surface hydrophilicity and anti-fouling properties. The inclusion of 1.5 wt % n-ZnO and 5 wt % PEG to the pristine PEES membrane resulted in a higher flux of 233.76 L m-2 h-1, 70.09 % of water content, 47.46° of contact angle, the porosity of 30.20 %, and hydraulic resistance of 0.22 kPa/Lm-2h-1. Anti-fouling properties of the fabricated membrane were assessed using a model foulant BSA, which revealed a high flux recovery ratio value. As a result, the PEG and n-ZnO incorporated membrane is more hydrophilic than the virgin membrane. In addition, the prepared PEES/PEG/n-ZnO membrane showed a significant increase in metal ions and protein rejection. Furthermore, an antibacterial test of the membrane revealed that the PEG and n-ZnO composite membrane outperformed the bare PEES membrane in terms of antibacterial capabilities. Overall, the findings reveal that combining n-ZnO and PEG resulted in a membrane with improved anti-fouling capabilities and hydrophilicity, making it suitable for water purification.

A comprehensive review on immobilized microbes - biochar and their environmental remediation: Mechanism, challenges and future perspectives.

The environment worldwide has been contaminated by toxic pollutants and chemicals through anthropogenic activities, industrial growth, and urbanization. Microbial remediation is seen to be superior compared to conventional remediation due to its low cost, selectivity towards particular metal ions, and high efficiency. One key strategy in enhancing microbial remediation is employing an immobilization technique with biochar as a carrier. This review provides a comprehensive summary of sources and toxic health effects of hazardous water pollutants on human health and the environment. Biochar enhances the growth and proliferation of contaminant-degrading microbes. The combined activity of biochar and microbes in eliminating the contaminants has gained the researcher's interest. Biochar demonstrates its biocompatibility by fostering microbial populations, the release of enzymes, and protecting the microbes from the acute toxicity of surrounding contaminants. The current review complies with the immobilization technique and remediation mechanisms of microbes in pollutant removal. This review also emphasizes the combined utilization, environmental adaptability, and the potential of the combined effect of immobilized microbes and biochar in the remediation of contaminants. Challenges and future outlooks are urged to commercialize the immobilized microbes-biochar interaction mechanism for environmental remediation.

A review on extraction of polysaccharides from crustacean wastes and their environmental applications.

Disposal of biodegradable waste of seashells leads to an environmental imbalance. A tremendous amount of wastes produced from flourishing shell fish industries while preparing crustaceans for human consumption can be directed towards proper utilization. The review of the present study focuses on these polysaccharides from crustaceans and a few important industrial applications. This review aimed to emphasize the current research on structural analyses and extraction of polysaccharides. The article summarises the properties of chitin, chitosan, and chitooligosaccharides and their derivatives that make them non-toxic, biodegradable, and biocompatible. Different extraction methods of chitin, chitosan, and chitooligosaccharides have been discussed in detail. Additionally, this information outlines possible uses for derivatives of chitin, chitosan, and chitooligosaccharides in the environmental, pharmaceutical, agricultural, and food industries. Additionally, it is essential to the textile, cosmetic, and enzyme-immobilization industries. This review focuses on new, insightful suggestions for raising the value of crustacean shell waste by repurposing a highly valuable material.

Isolation of moderately halotolerant bacterial strains, associated with coral Porites lutea from Gulf of Kachchh: Antibacterial activity and PHB production.

The marine ecosystem contains a solution for food, shelter, pharmaceutical problems and has a key role in the economy of the country as tourism. The Gulf of Kachchh, known for its high tides and the coral reefs are less explored for its antibiotic activity due to the coral bleaching and diseases. The bacterial strains in the coral Porites lutea are determined to possess antibiotic activity against bacterial strains such as E.coli, P. aeruginosa, S. aureus and S. faecalis. Among thirty bacterial strains isolated from the tissue, skeleton and mucus, two bacterial strains resulted in the better antagonistic activity. The antibiotic compound extracted from both the bacteria elucidated to be 4-[(2E)-4-hydroxypent-2-en-1-yl]-5,6-dihydro-2H-pyran-2-one. Further, through ADMET prediction it was inferred that it is an effective drug lead as it reports less toxicity and better drug-likeliness. The study also includes the effect of Poly Hydroxy Butarate (PHB) production by the isolated bacterial strain.

Green synthesized cobalt oxide nanoparticles with photocatalytic activity towards dye removal.

The present study aimed at the synthesis of cobalt oxide nanoparticles (CONPs) mediated by leaf extract of Muntingia calabura using a rapid and simple method and evaluation of its photocatalytic activity against methylene blue (MB) dye. UV-vis absorption spectrum showed multiple peaks with an optical band gap of 2.05 eV, which was concordant with the literature. FESEM image signified the irregular-shaped, clusters of CONPs, and EDX confirmed the existence of the Co and O elements. The sharp peaks of XRD spectrum corroborated the crystalline nature with a mean crystallite size of 27.59 nm. Raman spectrum substantiated the purity and structural defects. XPS signified the presence of Co in different oxidation states. FTIR image revealed the presence of various phytochemicals present on the surface and the bands at 515 and 630 cm-1 designated the characteristic Co-O bonds. VSM studies confirmed the antiferromagnetic property with negligible hysteresis. The high BET specific surface area (10.31 m2/g) and the mesoporous nature of the pores of CONPs signified the presence of a large number of active sites, thus, indicating their suitability as photocatalysts. The CONPs degraded 88% of 10 mg/L MB dye within 300 min of exposure to sunlight. The degradation of MB dye occurred due to the formation of hydroxyl free radicals on exposure to sunlight, which followed first-order kinetics with rate constant of 0.0065 min-1. Hence, the CONPs synthesized herein could be applied to degrade other xenobiotics and the treatment of industrial wastewater and environmentally polluted samples.

Prevalence of differential microbiome in healthy, diseased and nipped colonies of corals, Porites lutea in the Gulf of Kachchh, north-west coast of India.

Coral reefs are constantly subjected to multiple stresses like diseases and fish predation, which can profoundly influence the coral microbiome. This study investigated the differences in bacterial community structure of healthy, white syndrome affected and blenny nipped coral colonies of Porites lutea, collected from the coral reefs of Gulf of Kachchh, north-west coast of India. Present study observed that the stressed coral colonies harbored more OTUs and contained higher diversity values compared to healthy corals colonies. Similarly, beta diversity analysis indicated the dissimilarities among the three coral samples analyzed. Though the taxonomy analysis indicated bacterial phyla like Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria among the entire coral samples studied, there was a variation in their relative abundances. Huge variations were observed in the relative dominance at the bacterial genera level. About 13phyla and 11 genera was identified in healthy coral. The PBN sample was found to contain Proteobacteria, Cyanobacteria, Verrucomicrobia, and Lentisphaerae as dominant phyla and Endozoicomonas, Dyella, Woeseia, and Winogradskyella as dominant genera. The PWS sample contained Proteobacteria, Lentisphaerae, Spirochaetes, and Tenericutes as dominant phyla and Endozoicomonas, Arcobacter, Sunxiuqinia, and Carboxylicivirgia as dominant genera. Among the healthy samples, sequences belonging to Uncultured Rhodospirillaceae were dominant, while Woeseia and sequences belonging to Uncultured Rhodovibrionaceae were dominant among the blenny nipped white syndrome infected corals. Although any previously established pathogen was not identified, present study revealed the presence of a potentially pathogenic bacterium, Arcobacter, among the diseased corals. It also demonstrated a dynamic microbiome among the Porites lutea colonies on subjecting to various stresses.

Emerging aspects of metal ions-doped zinc oxide photocatalysts in degradation of organic dyes and pharmaceutical pollutants - A review.

In recent periods, a broad assortment of continual organic contaminants has been released into our natural water resources. Indeed, it is exceedingly poisonous and perilous to living things; thus, the elimination of these organic pollutants before release into the water bodies is vital. A variety of techniques have been utilized to remove these organic pollutants with advanced oxidation photocatalytic methods with zinc oxide (ZnO) nanoparticles being commonly used as a capable catalyst for contaminated water treatment. Nevertheless, its broad energy gap, which can be only stimulated under an ultraviolet (UV) light source, and high recombination pairs of electrons and holes limit their photocatalytic behaviors. However, numerous methods have been suggested to decrease its energy gap for visible regions. Including, the doping ZnO with metal ions (dopant) can be considered as an effectual route not only the reason for a movement of the absorption edges toward the higher (visible light) region but also to lower the electron-hole pair (e--h+) recombination. This review concentrated on the impact of dissimilar types of metal ions (dopants) on the advancement in the degradation performance of ZnO. So, this work demonstrates a vital review of contemporary attainments in the alteration of ZnO nanoparticles for organic pollutants eliminations. Besides, the effect of doping ions including transition metals, rare earth metals, and metal ions (substitutional and interstitial) concerning numerous types of altered ZnO are summarized. The photodegradation mechanisms for pristine and metal-modified ZnO nanoparticles are also conferred.

Iron doped activated carbon for effective removal of tartrazine and methylene blue dye from the aquatic systems: Kinetics, isotherms, thermodynamics and desorption studies.

In the current research work, the activated carbon synthesized from the plant species Delonix regia is doped with iron oxide nanoparticles and enforced as a nanosorbent for the effective extermination of Tartrazine (TAR) and Methylene blue (MB) dyes. This nanosorbent is prepared from the bark powder of the Delonix regia and subjected to chemical activation; Furthermore, the synthesized biosorbent were characterized using FTIR, SEM, TGA, and XRD to understand their functional properties and structural morphology. The optimum effectiveness adsorption of Tartrazine and Methylene blue has been investigated by using different key parameters. The conclusions have shown the highest removal percentage at a pH of 3 and 6 for Tartrazine and Methylene blue, respectively. For the various initial concentrations, the adsorption percentage reached equilibrium after 60 min and 90 min for TAR and MB. The adsorption equilibrium values were applied to various isotherms models. The adsorbent showed a higher removal capacity of 357.142 mg g-1 and 147.058 mg g-1 and for MB and TAR respectively. The kinetic data were best fits to pseudo second order model. The thermodynamic parameters indicated that this adsorption process was found to be spontaneous, exothermic and feasible at different temperatures. These results have shown that the prepared adsorbent is an environmentally friendly and suitable material for the elimination of TAR and MB from water systems.

Utilization of surface-active compounds derived from biosolids to remediate polycyclic aromatic hydrocarbons contaminated sediment soil.

In the present study, surface-active compounds (SAC) were extracted from biosolids using an alkaline treatment process. They were tested for their remediation efficiency of crude oil-contaminated sediment soil and was compared with Triton x-100. The SAC exhibited a similar soil washing efficiency to that of the commercial Triton x-100, and under the optimized soil washing parameters, SAC exhibited a maximum of 91% total polycyclic aromatic hydrocarbons removal. Further, on analysing the toxicity of the soil residue after washing, it was observed that SAC from biosolids washed soil exhibited an average of 1.5-fold lesser toxicity compared to that of Triton x-100 on different test models-earthworm, a monocot, and dicot plants. The analysis of the key soil parameters revealed that the commercial surfactant reduced the soil organic matter and porosity by an average of 1.3-fold compared to SAC. Further, the ability of surfactants to induce toxicity was confirmed by the adsorption of the surfactants on the surface of the soil particles which was in the order of Triton x-100 > SAC. Thus, this study suggests that SAC can be applied as an effective bioremediation approach for contaminated soil for a greener and sustainable ecosystem.