Search

The utility of Nru clay for industrial application, which was taken from the Nsukka local government area in Enugu State, Nigeria, is assessed in this study for its physical and chemical properties. The clay was investigated chemically which showed SiO 2 51.2%, Al 2 O 3 18.3% as the predominant constituents while other metallic oxides such as Fe 2 O 3 5.3%, MgO 2.2%, Na 2 O 1.8%, CaO 1.4%, K 2 O 1.3% and MnO 0.7% were present in considerable proportion. The physical and mechanical analysis acknowledged a range in the linear shrinkage (4.17 - 6.25%), total shrinkage (7.8 - 10.2%), apparent porosity (36.92 – 26.58%), apparent density (2.59 - 2.37 g/cm3), bulk density (1.63 - 1.74 g/cm3), water absorption (22.64 – 15.33%) and modulus of rupture (6.70 – 9.15 kg/cm2) with an increase in firing temperature from 900°C to 1200°C. Nru clay can withstand heat without melting or deforming at temperature up to 1200 °C and exhibited reasonable plasticity with a modulus of plasticity of 1.42. We can infer from our investigation that Nru clay is a potential raw material for industries in the production of ceramics, high melting clays, fired bricks, and paints. Alternatively, the clays’ properties can be tailored to achieve superior physical and mechanical properties by enhancing them with additives. Therefore, it can be employed to cushion the exorbitant cost of importing clay minerals from other nations.

In this work, the adsorption of ciprofloxacin onto yam peel biosorbent was studied by batch method. The equilibrium isotherm analysis of the adsorption process was evaluated to provide insight into the removal mechanism. A decrease in the percentage removal (75.0 – 60.8%) and an increase in adsorption capacity (6.0 – 24.3 mg/g) with an increase in ciprofloxacin concentration from 20 – 100 mg/L was obtained. The isotherm was analyzed by the Langmuir, Temkin, Freundlich, and Scatchard models, and the best fit was obtained for the Freundlich model with a R2 of 0.9918. The separation factor in the range of 0.238 – 0.609 and the Freundlich adsorption intensity of 1.492 indicated a favorable adsorption of ciprofloxacin on yam peel. A monolayer adsorption capacity of 42.81 mg/g was obtained for yam peel which was higher than other efficient adsorbents. The Scatchard model gave a linear fit to the uptake data with R2 of 0.9653 and sum square error of 0.008. The isotherm analysis revealed complex adsorption involving multi mechanisms in the overall process. The results of this investigation showed that yam peel could be utilized as an efficient agricultural waste for the adsorption of ciprofloxacin from wastewater.

The physico-chemical and microbial examination of Ajali River in Ezeagu Local Government Area (LGA) of Enugu State, South-eastern Nigeria, were carried out to assess the characteristics of the water for potability. Water samples were collected from three sampling points, including the one close to the brewery effluent discharge into the river and two different points that were affected by non-point sources. Altogether, eighteen samples were collected for two years during the dry, early and late rainy seasons. The physico-chemical, as well as microbial analyses of the samples, were determined following the standard methods. Significant spatial and seasonal variations (p

The energy demand is on the global increase as the world economy is increasing steadily. Hence, the need to develop energy-saving technology with local raw materials and abundant waste materials becomes paramount. The mixtures of Enugu Iva-pottery clay, Nsu clay and PKS were evaluated to improve the quality of locally produced refractory for pyro-processing industries. The chemical and mineralogical composition of the PKS and the clay were determined. Eight recipes were made by varying PKS with quartz from 5 to 35% and produced by the wet pressing technique, then fired to 1200 °C and 1300°C respectively. The mechanical properties were determined by the Modulus of Rupture test, also, the bulk density, linear shrinkage, total shrinkage, apparent porosity, water absorption and thermal efficiency tests of the produced refractories were ascertained. The recipe with 15% PKS sintered well at 1300°C and gave the best optimum results of 1.76g/cm3 bulk density, 6.49% linear shrinkage, 21.384% apparent porosity, 20 cycles of spalling tests at 1300 °C. The results comply well with the standards of refractory properties. The PKS additives have shown significant improvement in the properties of the locally produced refractories and waste control; hence, can promote sustainable development of the local pyro-processing industry.

The efficiency of various benzimidazole derivatives as mild steel corrosion inhibitors in HCl and H2SO4 medium was evaluated using quantum chemical methods. The AM1 semi-empirical method and Density Functional Theory (DFT) at the B3LYP/6-31G* level were used. The orbital energies (EHOMO and ELUMO), Separation Energy (ELUMO-EHOMO), Dipole moment (µ), Log P, Polarizability, molecular volume, molecular weight, Hardness (η) and Softness (S) are the computed quantum chemical characteristics linked to inhibitory efficiency. There was a strong link between quantum chemical parameters and experimental inhibition efficiency. The findings revealed that the Inhibition Efficiency was linked to a number of quantum chemical factors. The 2-mercaptobenzimidazole derivative had a higher Inhibition Efficiency (IE) than the other benzimidazole derivatives, according to the results.

This investigation is on the treatment of a fibre-cement industry effluent (FCIE) using activated carbon (AC) adsorbent prepared by chemical activation (60% phosphoric acid) of Gossweilerodendron caesalpinoideae (GC) stem waste. The GCAC adsorbent was characterized by determination of the proximate and functional properties. The chemical groups, morphology and mineral phases of the GC stem waste and GCAC were studied by FTIR, SEM, and XRD methods, respectively. Kinetic and thermodynamic studies were carried out using total dissolved solids (TDS) as evaluating parameter. Effects of adsorbent dosage (5-40 g/L), contact time (0-60 min), and temperature (20-40 °C) on the effluent decontamination were investigated. Results from the characterized supernatant showed up to 97% removal of the contaminants using 40 g/L of GC adsorbent at effluent pH 7.4. The concentrations of TDS obtained by U-V spectrophotometric analysis were fitted to pseudo-first and pseudo-second order, Elovich and intraparticle kinetic models. The adsorption followed the pseudo-second order rate equation. Obtained free energy and enthalpy of adsorption values indicated non-spontaneous and endothermic adsorption. The study affirmed that the bioadsorbent, GCAC can be used for FCIE treatment.

Biomethanation potentials of pig dung co-digested with pineapple peels were investigated. Various blends of pig dung with pineapple peels were charged respectively into 50 kg prototype digesters labeled A to C. Digesters D and E were charged with only pineapple peels and pig dung respectively. Proximate and physico-chemical analyses were determined on the slurry using conventional methods. The wastes were subjected to anaerobic digestion for 35 days at mesophilic temperature range of 25 to 37°C. Relative humidity, ambient temperature, pH, slurry temperature and volume of gas were monitored and recorded on daily basis. Biogas yield increased progressively with higher pig dung blend. Onset of gas flammability was observed on the 5th day for blends of pig dung and pineapple peels, as well as for pineapple peels alone while for pig dung alone, it was observed on the 6th day. This was as a result of lower nitrogen contents of pineapple peels blends compared with that of pig dungs alone, a factor which favours early onset of flammability. Biogas generated from the mixture ranged from 65- 71% CH4, 28 -34% CO2, and traces of hydrogen sulphide and carbon (II) oxide. The biogas was subsequently stored in a gas cylinder using modified pressure system. This study is aimed at converting wastes such as pig dung and pineapple peels to useful energy and storing the gas produced in cylinders for easy accessibility.