Modified synthesis of nanoscale zero-valent iron and its ultrasound-assisted reactivity study on a reactive dye and textile industry effluents

Abstract

A B S T R A C TSynthesized nanoscale zero-valent iron (NZVI) particles were applied for the degradation of a reactive dye Remazol Black B 133 and textile effluent. XRD and HR-TEM analysis of the synthesized particles showed body centered cubic crystal packing. The aggregates were spherical in shape and the size of the particles ranged from 5 to 15 nm. The reactive dye solution was substantially degraded by NZVI particles using ultrasonic irradiation under various experimental conditions created by varying NZVI dosages (0.15-0.30 g/L), initial dye concentration (25-200 mg/L), and pH (2-13). Experimental results suggest that NZVI particles work best within the pH range of 4-10. A unit gram of NZVI was found to degrade a maximum of 749.2 mg of RB B 133 dye and more than 80% of the dye was removed within 15 min of reaction time. During the degradation process, an oxidationreduction potential change from 196 to −577 mV was detected, indicating reductive condition is necessary for effective dye removal. FT-IR analysis of the end products of the degradation process indicated the presence of an amino (-NH 2 ) group resulting from the breakdown of the azo (-N=N-) group. Results suggest that the degradation followed pseudo-first-order kinetics with respect to dye concentration. The effluents of two textile industries were collected, characterized, and treated with NZVI particles, which led to the significant fall below the standard scale of American Dye Manufacturing Institute (ADMI). This lowering of ADMI value indicates that the overall color removal efficiency is irrespective of any specific dye present in the effluent.

Fabrication of ZnS Hollow Spheres and RGO-ZnS Nanocomposite Using Cysteamine as Novel Sulfur Source: Photocatalytic Performance on Industrial Dyes and Effluent

“…Usage of cysteamine hydrochloride renders the whole synthesis process less hazardous than conventional chemical methods. − Furthermore, we have studied the photocatalytic efficiency of both hollow spheres of ZnS and RGO-ZnS composite in the presence of a model “azo” dye (Direct Blue 53) and then it was applied on a real textile effluent to check the actual applicability of these photocatalyst. The most toxic chemical present in a textile effluent is the dye stuff itself, as more than 50% of dye mass gets dispersed to water during manufacturing and processing. − RGO-ZnS composite is found to be more effective than ZnS hollow spheres in removal of textile effluent, and with the help of physicochemical and photoluminescence study, we attribute this observation to efficient electron–hole separation at the interface of the two semiconducting systems. However, it is important to mention here that both of our as-synthesized materials (ZnS hollow spheres and RGO-ZnS composite) act as potential photocatalysts even at very low doses (Tables S1 and S2) as compared to earlier reports. ,− , In summary, we have successfully synthesized well-dispersed, uniform hollow spheres of ZnS and RGO-ZnS nanocomposites using a novel, ecofriendly sulfur source and effectively explored them for the degradation of textile effluent.…”

Enhanced Nitrate Ions Remediation Using Fe0 Nanoparticles from Underground Water: Synthesis, Characterizations, and Performance under Optimizing Conditions

“…The average crystallite size of the synthesized nZVI was determined using XRD via the Scherrer equation [ 23 ] as follows: where D is the size of particle in nm, θ is the Bragg angle obtained from 2 θ and corresponds to the peak intensity at the maximum, and β is the full width at half maximum (FWHM), [ 24 , 25 ]. The mean value of the calculated crystal size is found to be 10.23 nm.…”

Formulation of zeolite supported nano-metallic catalyst and applications in textile effluent treatment

“…They also noticed that one gram of nZVI removed approximately 749 mg of dye, by breaking the azo group into an amino group. They also suggested that dye removal efficiency was increased via increasing nanoparticles dosage [31]. Luo and coworkers demonstrated a complete removal of orange II dye using rectorite (a natural clay), as support for nZVI in 10 min treatment, while only 35% dye removal was observed by using unsupported nZVI [32].…”