STUDY OF THE INFLUENCE OF DISPERSITY AND CHEMICAL COMPOSITION OF NICKEL RENEUAL ALLOYS ON THE SPECIFICITY OF REDUCTION OF ADAMANTANE-CONTAINING UNSATURED NITRILE

The regularities of the reduction of adamantane-containing unsaturated nitrile-nickel-aluminum alloy are investigated. It has been shown that under the conditions of synthesis it is possible to carry out the simultaneous reduction of both the double bond and the nitrile group. It was found that the reduction of nitriles containing 1 hydroxyl group in the position leads to a significant decrease in the rate of the process. The effect of the grain size composition of the alloy and damping additives on the reduction of unsaturated nitriles has been studied.

CO2 Methanation: Nickel–Alumina Catalyst Prepared by Solid-State Combustion

The development of solvent-free methods for the synthesis of catalysts is one of the main tasks of green chemistry. A nickel–alumina catalyst for CO2 methanation was synthesized by solid-state combustion method using hexakis-(imidazole) nickel (II) nitrate complex. Using X-ray Powder Diffraction (XRD), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Hydrogen temperature-programmed reduction (H2-TPR), it was shown that the synthesized catalyst is characterized by the localization of easily reduced nickel oxide on alumina surface. This provided low-temperature activation of the catalyst in the reaction mixture containing 4 vol% CO2. In addition, the synthesized catalyst had higher activity in low-temperature CO2 methanation compared to industrial NIAP-07-01 catalyst, which contained almost three times more hard-to-reduce nickel–aluminum spinel. Thus, the proposed approaches to the synthesis and activation of the catalyst make it possible to simplify the catalyst preparation procedure and to abandon the use of solvents, which must be disposed of later on.

Assessment of Rainwater and Groundwater Quality in Izombe Town, Oguta Local Government Area of Imo State

Rainwater and groundwater quality in Izombe were assessed. Five water samples were collected from five (5) different locations, with at least one location from one of the four autonomous communities in Izombe, Oguta L.G.A of Imo State. The physicochemical and microbial parameters of rainwater and groundwater samples from Umuakpa, Ndeuloukwu, Ugbele, Ndioko, and Orsu were assessed using Varian Atomic Absorption Spectrophotometer (AAS). The study was aimed to assess the physicochemical and microbial qualities of groundwater and rainwater in Izombe and how these affect their health as individual members of the community, and their environment when compared to WHO standards. The water samples were collected from five different locations, with at least one location from each of the four autonomous communities, and were assessed. The result indicated that rainwater and groundwater pollutants in the community were turbidities, ammonia, copper and temperatures 7.59±0.02 ph, 6.42±0.28 nitrate, 59.56±0.50 ammonia, 0.29±0.07 phosphate, 0.88±0.03 iron, copper, lead, nickel, aluminum, mercury, manganese, cadmium, bacteria count, coliform count, and E-coli. Also, all the pollutant parameters were identified, only iron, copper, aluminum, and bacteria count were not identified as being associated with petroleum products and exploratory activities. This research has broadened the understanding of the suitability of Izombe water sources for both consumption and other purposes. The findings show that the rain and groundwater sources of the community are not fit for human consumption, due to the contaminants inherent in them, attributed majorly to the oil production activities in the area which corroborates other research studies.

Effect of plastic deformation on mechanical properties and corrosion resistance of nickel-aluminum bronze

Purpose Nickel-aluminum bronze (NAB) has been widely used in ship propellers. It is always subjected to local micro-plastic deformation in service environments. This paper aims to study the influence of plastic deformation on the mechanical strength and corrosion resistance of NAB in 3.5 Wt.% NaCl solution. Design/methodology/approach Scanning electron microscope and X-ray diffraction were used to analyze the microstructure of NAB alloy with different plastic deformations. Mechanical properties of the sample were measured by tensile experiment, and corrosion behavior was studied by electrochemical measurements and the long-term immersion corrosion test. Findings Results showed that the plastic deformation caused lattice distortion but did not change the microstructure of NAB alloy. Microhardness and yield strength of NAB were significantly improved with the increase of deformation. The lattice distortion accelerated the formation of corrosion product film, which made the deformed alloy show a more positive open-circuit potential and an increased Rp. However, during the long-term immersion corrosion, the corrosion resistance of NAB alloys deteriorated with the increase of plastic deformation. This is because larger plastic deformation brought about higher internal stress in corrosion product film, which resulted in the premature peeling of the film and the loss of its protective effect on the alloy substrate. Originality/value Tensile plastic deformations were found to cause a decline in the corrosion resistance of NAB. And the mechanism was clarified from the evolution of corrosion products during the corrosion process.