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Cyanide compounds are widely used in some electroplating, chemical and metallurgical industries. They are often found in their liquid discharges. This work highlights the performance of an activated alumina-supported copper catalyst in the removal of cyanide by oxidation with hydrogen peroxide in aqueous solution. The influence of catalyst dose, initial molar ratio of hydrogen peroxide/cyanides, temperature, and catalyst reuse was studied. The activated alumina-supported copper significantly enhanced the reaction rate showing a good catalytic activity. The efficiency of cyanide elimination was increased after 30 minutes of oxidation from 48% to 98% by increasing the catalyst dose from 1 to 10 g/L. Rising the temperature from 30°C to 40°C promoted cyanide removal. The catalyst can be recycled four times and show good stability. The kinetics of cyanide oxidation was revealed to be pseudo-first order with regarding cyanides. The rate constants as well as the activation energy were determined.

Treatment of tannery effluent is a key issue that requires novel research. The presented work is an attempt to carry out advanced oxidation process in a Multi-orifice Oscillatory Baffled Column using ozone as oxidizer and compare the extent of treatment with sono-catalytic treatment with TiO2 as catalyst. Studies have been carried out to understand the effect of treatment time, concentration of effluent and oscillation frequency upon ozonation and the effect of power of ultrasound, time of treatment and catalyst loading for sono-catalytic treatment. For ozonation the COD, BOD and TDS reduction obtained are 88.8%, 84.01%, 90.73% respectively and for sono-TiO2 treatment the reduction of COD, BOD and TDS obtained are 91.2%, 91.5%, 94%. Optimization and analysis of variables is carried out to identify the effective factors for treatment.

In this research, we provide a method for synthesizing ZnO nanoparticles using Moringa Oleifera Leaf (M.O Leaf) Extract. UV-VIS Spectroscopy, Scanning Electron Microscopy, EDS, X-ray diffraction and Fourier Transform Infrared Spectroscopy (FTIR) were used to create and characterize ZnO nanoparticles. The spherical size structure of the synthesized nanoparticles with an average grain size of 1 nm was validated by SEM, EXD, and XRD analysis. After the sunlight exposure, the photocatalytic reagent was used to break down the organic dyes in the synthesized ZnO nanoparticles. Nearly 96–97% of the titan yellow and Congo Red dyes were broken down by ZnO nanoparticles.

The biological synthesis of nanomaterials is drawing immense interest because of their non-hazardous nature and enormous antimicrobial application. In the present study, we explored Polygonatum geminiflorum Decne for phytochemical profiling and biosynthesis of silver nanoparticles to control soft rot/blackleg and bacterial wilt pathogens of potato through in vitro experiment. Phytochemical screening indicated the presence of important secondary chemicals including tannins, glycosides, flavonoids and terpenoids, while, gas chromatography-mass spectrophotometry (GC-MS) study of leaf extract showed the presence of 30 phytochemicals, the most prominent among which included ç-Sitosterol and n-Hexadecanoic acid. The GC–MS qualitative analysis also supported the presence of bioactive compounds responsible for metal reduction processes and synthesized nanoparticles stabilization. In vitro study showed that concentration of 100µg/mL of AgNPs and AgNPs-PE efficiently control both Erwinia carotovora and Ralstonia solanacearum. The outcomes have provided an improved protocol to use prepared AgNPs against the tested pathogens without health hazards.