Search

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. [ABSTRACT FROM AUTHOR]

The application of biosurfactants for the degradation of various toxic compounds has received much attention among researchers worldwide. A stimulated degrading method was carried out in this research to determine the efficiency of surfactant on the biodegradation of aromatic amine 4-Aminobiphenyl (4-ABP). The biosurfactant mediated process is an alternative strategy for chemical surfactants because chemical surfactants are toxic and nonbiodegradable. The bacterium was isolated through the enrichment process and identified using 16S rRNA sequencing method. The molecular characterization showed that the isolate belongs to Brevibacterium casei- 4AB. Biosurfactant produced in this study was examined through screening activities like oil spreading, emulsification activity and surface tension measurement. Instrumental characterization like Fourier Transform Infrared Spectrophotometer (FT-IR) results suggested that there is a presence of NH group, aliphatic hydrocarbons, ester groups, amide and alkenes and further Gas chromatography- Mass Spectrometry (GC-MS) results confirmed the presence of fatty acids such as Hexadecanoic and Octadecadienoic acid which showed that the produced surfactant is lipopeptide. Protein content and lipid content in the biosurfactant was found to be 18 ± 0.8% and 30 ± 0.1%. The degraded metabolites of 4-ABP were analyzed through the GC-MS process which revealed the presence of metabolites such as 5-Amino-2-methoxy phenol. ga1 • This is the first report on hazardous 4-Aminobiphenyl (4-ABP) degradation using Brevibacterium casei. • Lipopeptide exhibited best emulsification (66 ± 0.65%), surface activity (29.6 m Nm−1) and oil spreading (2.6 ± 0.25 cm). • Biosurfactant enhanced the bacteria for degradation of 4-ABP up to 9 mgL−1. • GC-MS process revealed the presence of metabolite such as 5-Amino-2-methoxy phenol. [ABSTRACT FROM AUTHOR]

The utilization of fossil fuels causes adverse effects on the human and environment and the world is facing the depletion of these resources. The conventional technologies available for hydrogen production create greenhouse gases which cause a serious threat to the surroundings. Hence, there is a need to create a renewable and alternative technique for hydrogen production. The biological method acts as renewable technology to conventional technologies. For the present and future generations, the development of bioreactors may provide a sustainable route to meet cleaner hydrogen production. The conventional methods like reforming process, gasification process, thermochemical method, water electrolysis and photoelectrochemical method are not sustainable which emits toxic gases and requires a large amount of energy but in the application of bioreactors the cleaner fuel can be obtained and wastewater can be treated efficiently. The objectives of this review are to estimate the efficiency of reactors involving dark fermentation reactors (suspended and attached growth reactors), photobioreactors (tubular and flat plate reactors) and microbial electrolysis cell bioreactors along with their recent advancements in hydrogen production. This article also highlighted the comprehensive review about the substrate utilization, waste treatment, the principle of reactor process and recent process developments. Although several methods are available for hydrogen production, important and innovative discoveries and process configurations in pilot-scale are needed to estimate the potential of each bioreactor to provide sustainable and cleaner fuel production. Through this review, the present status of bioreactors in hydrogen production and their scale-up opportunities can be determined. • The recent advancements on the bioreactors for biohydrogen production has discussed. • Summarized the environmental conditions required for higher rate of hydrogen production. • Outlined the best reactor to bring the hydrogen production in industrial scale. • Explained the basis for managing the technical berries raised in hydrogen production. [ABSTRACT FROM AUTHOR]

The objective of the current study was focused on the potential adsorption capability of a biogenic hydroxyapatite/iron nanoparticles-based composite tailored for the elimination of toxic pollutant, Cd(II) ions. Morphological along with physicochemical properties of composites were analyzed by different techniques including Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). It has been noticed an increase in cell parameters of prepared composites with an increase in the amount of nanoparticles. The best adsorbent was found to be the one with a 5% amount of nanoparticles (P 400 F e (5%)). The kinetics studies have shown that the pseudo-first-order-models were in good agreement for the removal of Cd(II) ions onto P 400 Fe(5%) at any concentration, suggesting a physisorption mechanism. Besides, isotherms analysis has consistently revealed Freundlich as the model better explained the isotherm data, with a maximum removal capacity of 392.3 mg g−1, higher compared to many adsorbents. Thermodynamically, the removal adsorption process of Cd(II) ions onto the composite favorable, exothermic, and spontaneous. The regeneration study has been also investigated with reusability used until four cycles. The overall results pointed out the suitability and efficiency of the prepared biogenic composite for the elimination of metal pollutants in wastewater. [Display omitted] • Biogenic composites were successfully prepared from slaughterhouses by-product and iron nanoparticles. • The maximum adsorption capacity of P 400 Fe(5%) was up to 392.3 mg g−1. • The isotherm and kinetic data best fits Freundlich and pseudo-first-order models. • The mechanism could be due to cationic exchange between Ca2+ and Cd2+. • The biogenic composite was effective for four consecutive regeneration cycles. [ABSTRACT FROM AUTHOR]