Retarding Mild Steel Corrosion using a Blend of Schiff Base Metal Complex and Neem Plant Extract

Prepared inhibitor blend of synthesized Co (II) Schiff base complex and Azadirachta indica extract was applied as anti-corrosion agent to mild steel in acidic (0.5 M H2SO4) medium. A synergistic performance was the lookoutof the study, with the green inhibitor as the synergistic additive. Inhibitors are characterized by their active functional groups, UV-visible profile and bioactive compounds. Surface characteristics of polished, corroded and coated mild steels were investigated using weight loss experiments. Results of phytochemical screening shows the presence of possible bioactive species, including glycoside, tannins and phenolic compounds, saponin, Steroids and Triterpenoids. Weight loss experiments at temperature range of 303 K to 323 K were performed. Inhibition efficiencies of the three systems demonstrated increments with increasing inhibitor concentration and decreases as the temperature rises, thus characterizes physi-sorption mechanism. The ethanol extract of Azadirachta indica leaves, cobalt (II) Schiff base complex and the blend in 0.5 M H2SO4 gives up to 46.88 %, 31.16 % and 59.69% inhibition efficiencies respectively at 323 K. The adsorption equilibrium data of these inhibitors on the surface of mild steel fits the Freundlich, Langmuir and Dubinin - Raduskevich isotherms at varying extent and the values of ΔGads for all the isotherms were below 20 kJ/mol, suggesting physical adsorption. The estimated thermodynamic parameters support process spontaneity. Generally, enhanced performance of blend inhibitor showed a synergistic effect (S1> unity) and proved the effectiveness of derived blend as potent inhibitor of mild steel corrosion in acidic medium.Keywords: Antagonistic, Blend, Complex, Inhibitor, Synergisti

Evaluating the Effects of Roofing Materials on Physicochemical Properties of Harvested Rainwater in Warri, Delta State, Nigeria

This study was aimed at investigating the effects of roofing materials on water quality, in Warri district. Random sampling technique was used to collect forty two (42) rainwater samples from different roofing materials made from (asbestos, zinc, aluminium and thatch roof) including the control (rainwater collected directly from the sky) in Warri refinery and petrochemical company(WRPC) and military formation area(MLF). The harvested rainwater samples were analyzed using Atomic adsorption spectrophotometer, AAS, TDS meter, heating plates, electrical conductivity meter, retort stand, pH meter, Turbidity meter, Conductivity meter etc. Results obtained revealed that most of physiochemical parameters of rainwater samples analyzed were generally below the WHO threshold. The results also indicate the presence of Pb, Fe and Cr, in the harvested rainwater samples, of which Pb that is a poisonous metal is above the maximum WHO allowable limit of 0.3 mg/L. From the results, scientifically, it is advisable that the first flush from all the rooftops cannot be used because of high levels of dirt, rust etc. Fifth flush and above can be used for domestic chores like washing, mopping, irrigation, cleaning, laundry etc. without further purification, but should be subjected to simple water treatment like boiling and chlorination before it can be consumed. &nbsp

Comparative Analysis of Mineralogical Characteristics of Clay-Rich Soil Samples obtained from Gbajimba, Angbaaye and Makurdi Areas of Benue State

The elemental concentrations and mineralogical composition of soil samples from Gbajimba, Angbaaye and Makurdi areas of Benue state were evaluated. Their clay fractions (particles smaller than 2 microns) studied through a series of mineralogical, chemical and physico-chemical analyses showed that the colour test of the sample showed brown to red. The study suggested that morphology of kaolinitic and quartz minerals is influenced by the parent material (i.e. feldspars or micas) and degree of chemical weathering. The pH values of pore water from clay samples showed acidity, ranging from 4.93 - 6.96. The electrical conductivities (EC) of the samples ranged from 2.68-3.48 mS/cm – 3.48mS/cm. The CEC results of the sample showed a 6.98-7.32 range. The results of X-ray diffraction (XRD), infrared spectroscopy (IR), Scanning Electron Microscopy (SEM) characterization showed that the soil samples from these three areas with clay-rich soil were a mixtures of kaolinite, quartz, muscovite, microline, pyrite, chlorite and sylvite, showing quartz present in all samples. The results obtained from XRF showed that the clay samples mostly composed of silicon (IV) oxide in Gbajimba(51.538%), Angbaaye (49.107%) and Makurdi (64.826%); Aluminum in Gbajimba (18.883%), Angbaaye (22.419%) and Makurdi(16.319%);Iron in Gbajimba (8.3230%), Angbaaye (8.8611%) and Makurdi (4.2672%); Manganese, phosphorous, titanium etc. These are the proportion of the major expected elements. Hence, the results from the analysis fell within the same range of results from other works studied

Adsorption of Pb2+ from aqueous solution by modified melon (Citrullus lanatus) seed husk.

The application of Modified Melon Seed Husk (MMH) an agricultural waste in the remediation of water contaminated with lead ions was investigated in the present study. Modification was done by soaking the melon seed husk in 0.5M NaOH solution. Batch kinetic and isotherm studies was performed to understand the ability of the adsorbents. Effect of some process variables were assessed viz: pH, initial metal ion concentration and sorbent dosage on the sorption process. The equilibrium sorption isotherm was studied using the Freundlich and Langmuir isotherm models. The results obtained showed that the process of the sorption fitted better with the Freundlich isotherm, implying that the sorption occurred on a heterogeneous surface of the MMH. The monolayer adsorptioncapacity determined from the Langmuir adsorption equation was found to be 52.08 mg/g which competes favourable with some other biosorbents. Data obtained from the kinetics of the sorption process via initial metal ion concentration were analyzed using pseudo second order, the pseudo first order model and intraparticle diffusion model. The sorption process obeyed the pseudo second order kinetic model better than the pseudo first order kinetic model, thus suggesting the role of chemisorption in the mechanisms of the sorption. The intraparticle diffusion model showed that intraparticle diffusion is not the singular rate limiting step in the sorption process. The kinetic parameters suggest that adsorption of lead ions by MMH was favourable. Overall, the present findings suggest that MMH, an environmentally friendly, efficient and low-cost biosorbent is useful for the removal of Pb2+ from aqueous media. Key words: Adsorption, Isotherm, Kinetics, Lead, Melon seed Husk, Wastewate

Adsorptive Removal of Cd2+ and Zn2 From Aqueous System by BSG

The potential utilization of Brewer’s Spent Grain (BSG) was investigated in the removal of Cadmium and Zinc from aqueous system. Batch sorption process assessment of the effects of process variables showed that pH, initial metal ion concentration and dosage amount affect the sorption and uptake of Cd and Zn ions by BSG. Analysis of the sorption process using different kinetic models showed that the pseudo first order kinetic models gave poor descriptions of the process for Zn  was r2 = 0.5268 but a good one for Cd at r2 = 0.9618 while the pseudo second order kinetic model gave a good description of the process for both metal ions  (r2>0.98). The Pseudo second order rate constant obtained for Zn (1.0812mgg-1min-1) is than that for Cd (0.17mgg-1min-1).Equilibrium isotherm analysis of the sorption process data showed that the Langmuir isotherm gave a better description of the process than the Freundlich for Cd while both Freundlich and Langmuir fitted very well for Zn sorption by BSG. The results of the studies indicate that the metal ions were favourably adsorbed onto the adsorbent with a removal efficiency of 94.46% for Zn and 77.81% for Cd. Keywords: Brewer’s Spent Grain, cadmium, zinc, sorption, Isotherm, Kinetics

Cobalt and nickel uptake by silica-based extractants

The pKas of ethyl/butyl phosphonate silica (EBP-Si) have been determined, and the removal of cobalt and nickel from solution was investigated as a function of various parameters and compared with those of Purolite S950. pH uptake experiments suggested a combination of ion exchange and acid dissociation of the surface occurring. Isotherm data, fitted using the Langmuir and Dubinin–Radushkevich (D-R) models, indicated that stronger complexes formed with S950 than with EBP-Si. Kinetic data, fitted using a pseudo-second-order model, suggested that the rate-determining process is the reaction of metal ions with the chelating functionality of the resin. Uptake by EBP-Si is two to three times faster than that on S950

Isolation of Catechin from Trichilla Emetica Whole Seeds

The purification of boiled water extract of T. emetica seeds resulted in the isolation of catechin, a known flavonoid. The structure was established on the basis of spectroscopic methods 1D (1H and 13C) NMR and 2D (COSY, HSQC and HMBC) NMR in addition to the mass spectrometry and comparison with literature data. The isolation of this compound is been reported for the first time in T. emetica

Determination of Triacylglycerol Composition of Trichilia emetica Seed Oil using GC-MS and 1H-NMR Spectroscopy

Trichilia emetica seed oil was analysed for their fatty acid profiles using GC-MS and 1H-nuclear magnetic resonance spectroscopy (1H-NMR). In the 1H-NMR spectrum, integrating the values of the signals of acyl, allylic and bis-allylic protons, the unsaturated fatty acid: monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) was quantitated. The relative percentage of saturated fatty acid (SFA) was determined by subtracting the relative amount of the total unsaturation from the total amount of fatty acid present in the oil. The procedure was verified by using GC-MS to determine the fatty acid methyl esters in the oil sample. The percentage triacylglycerol conversion to its corresponding methyl esters was determine by 1H NMR and was calculated to be 94%. A total of six FAMEs were identified in the seed oil by the NIST library match software and the fragmentation pattern data of GC/MS. The results obtained from the two methods were 55 % saturated (C14:0, C16:0, C18:0), 35% monounsaturated (C18:1) and 10 % polyunsaturated (C18:2 and C18:3). Generally, the 1H-NMR results were in good agreement with gas chromatographic (GC) analyses. In conclusion, the 1H-NMR-based procedures is fast as it does not require the oil to be derivatized and can be applied to neat T. emetica seed oil

The Effect of Processing Methods on the Nutritional Quality of Moringa Herbal Tea Powder

This study investigates the effect of processing methods on the nutritional quality of moringa herbal tea. Fresh moringa leaves were harvested and processed to moringa tea powders by the following methods: Oven drying (OD), Blanched-oven drying (BODM), Oxidised-Oven drying (OOD), Fermented-oven drying (FOD), and Blanched-fermented-oven drying (BFOD). Analysis carried out includes proximate, micronutrients composition, and sensory evaluation. Results showed that fat content range from1.2±0.24% to 3.11±0.23, fibre 2.5±0.54% to 4.29±0.23%, ash content range from 6.90±0.021% to 8.50±0.77%, Moisture 7.47±0.63% to 10.77±0.77%, proteins range from 25.00±0.40% to 28.71± 0.404%. Vitamins were in the range of 2.85±0.012 mg/100 g to 4.38±0.401 mg/100g for vitamin C, 14. 195±0.008 mg/100 g to 17.823±0.207 mg/100 g for vitamin E. Vitamin B1 ranges from 0.507± 0.007 mg/100 g to 1.078±0.002 mg/100 g. No significant difference was observed in provitamin A and vitamin E. Mineral composition varies from 4.12±0.00 to 7.00±0.00 mg/100 g (Zn), 105.20±0.00 to 156.15±0.00 mg/100 g (Ca) and 123.85±0.00 to 234.25±0.00 mg/ 100 g (K). The overall acceptability for the sensory attributes of the moringa herbal tea, with the sensory score of6.07±1.847 and 6.22±2.006 for sample FOD and BFOD, closed to that of commercial tea with an overall score of 7.44±1.649. Thus it can be concluded that the processing methods of herbal tea, has a significant role in the quality attributes and sensory appeal