Discharge of synthetic dyes from industries without treatment leads to major environmental problems. Present research highlighted the Mn-doped ZnO along with UV-induced photo degradation of Congo red (CR) dye through batch study. The synthesized Mn-doped ZnO (MDZO) was characterized by Transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). The results revealed that MDZO along with UV exposure degraded the CR dye up to 99.3% at concentration 4 mg/L, pH (7), adsorbent dose (0.6 g/L) and contact time (30 min). The degradation data nicely fitted with pseudo-secondary kinetics and the thermodynamic study suggest the said reaction is exothermic in nature. A statistical method, central composite design (CCD) was used to screen out the optimized condition of dye degradation. The interactions of main factors and optimal conditions were also evaluated by 3D surface plots. The statistical output clearly demonstrates that the dye degradation data is nicely fitted with very high goodness of fit and F value (86.19). Present research clearly suggested that Mn-doped ZnO along with UV could be an effective treatment towards degradation of Congo red dye.

In this work, single layered Ti3C2(OH)2 MXene nanosheets have been successfully prepared through a facile approach by etching Ti3AlC2 with alkaline solution treatment (KOH with minimum amounts of water). The structure and morphology of the produced nanosheets were evaluated through X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) analysis and the chemical composition was determined using an energy dispersion X-ray (EDX) spectrometer. Methylene Blue (MB) as a target pollutant adsorption and photocatalytic degradation tests were subsequently performed to assess the functionalities of hydroxyl-terminated MXene. MB removal using Ti3C2(OH)2 MXene in the dark in 20 minutes achieved an absorption-desorption balance of 51.2%, and then MB was degraded within 80 minutes under UV light irradiation with great efficiency. Our results presented that the powder of as produced exhibited good photocatalytic activity for three cycles photodegradation. The first-order rate constant (k) was calculated to be 0.0372 1/min. About 97% degradation of Methylene Blue dye in the solution was confirmed within 80 min of exposure to ultraviolet light.

Diazinon is an organophosphorus insecticide that was widely used in agriculture to control pests on crops. It acts as an acetylcholinesterase inhibitor, which means that it interferes with the normal functioning of the nervous system of insects, leading to their death. Diazinon can also have an impact on human health and the environment, as it can contaminate water and soil and pose a risk to non-target species, including humans and animals. This review paper shows the progress made in the last years in analytical methods applied for the purpose of extraction, detection and degradation of Diazinon as an important environmental pollutant. A variety of sampling and analytical methods have been developed to measure diazinon and its metabolites in different media. The most popular methods for the identification and analysis of Diazinon are liquid and gas chromatography, liquid-liquid extraction, and solid-phase extraction (SPE). The focus of this review is on the identification, measurement, and elimination of diazinon as a major soil pollutant. It begins with a discussion of analytical techniques, followed by an examination of methods for removing diazinon from soil.

In order to find an effective decolorization method for dye wastewaters, the present work aims at studying the treatment efficiency of an azo dye Acid Red 14 (AR14) by Electro-Fenton process using an undivided electrochemical cell containing different electrode materials. The optimal removal efficiency was obtained using carbon felt or glassy carbon (cathode) and platinum (anode) electrodes. The method is based on the reaction of electrochemically produced hydroxyl radicals leading to oxidative degradation of the AR14. To find the best conditions for treatment of AR14 dye, the effects of Fe2+ concentration, current density, the effect of pH initial, and the nature of support electrolyte were studied. The results showed 94 % removal efficiency in 30 minutes with 120 mA/cm2 of electrolysis current, 0.2 mM of Fe2+, and pH = 3. However, the decolorization efficiency measurements confirmed that the Electro-Fenton process with the platinum anode and the carbon felt cathode was more efficient.