Applied Chemistry

The biosorption is an effective and versatile method and can be easily adopted in low cost to remove heavy metals from large amount of industrial wastewaters. The biocarbon obtained from medicinal plant called Ocimum sanctum (Lamiaceae) is considered as a cheap materials for the removal of lead ions for aqueous solution. From batch biosorption studies, the effect of pH, contact time, different concentration of Pb(II) ions were used to estimate the optimum biosorption conditions. Removal efficiency of the biocarbon for Pb(II) ion in aqueous solution is maximum (87.5%) at pH 5.5. The effective contact time is 150min and the optimum biocarbon dose is 2.5g/100ml. The results indicate that, the percentage removal of metal ion increases progressively with the increase in amount of biocarbon dose. The activated biocarbon Ocimum sanctum was investigated as a replacement for the current expensive methods of removing metal ions from aqueous solutions.

The determination of heavy metal ions are limited by two difficulties, very low concentration of heavy metal ions which may be lower than the detection limit of many traditional analytical techniques such as atomic absorption spectrometry, colorimetric, and voltametry. And the interfering effects of the matrix. Calcium silicate (CS) is obtained as mentioned in the literature, This synthesized material, which have many applications in various walks of life will be under study in this research. In a new area of the most important areas of life and the environment, a water treatment and removal of some heavy ions such as Mn+2 and Fe+3 ions present in waste water and underground water were efficiently removed by (CS).

In the present work, the building waste material Red Kotta was treated with sulphuric acid and formaldehyde and used as an adsorbent for the removal of Methylene red from aqueous solution. The adsorption characteristics of Methylene red dye on untreated and treated Red Kotta powder was evaluated as a function of pH, adsorbent dose, initial concentration of adsorbate, contact time and temperature. The effective adsorption was found to be in pH range 2 to7, adsorbent dose 1gm to 5 gm, initial concentration (100ppm to 500ppm) and temperature range (283K to 313K). The results show that Red Kotta powder holds a great potential in removal of Methylene red dye from industrial wastewater.

Two composites - 1) Molybdenum dicarbonate-filter paper and 2) Molybdenum dicarbonate-activated carbon were synthesized and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis EDX. Using the method of UV-visible spectroscopy, the removal efficiences and adsorption capacities of these composites towards the removal of methylene blue (MB) from aqueous solution were compared. The findings of the MB adsorption with these composites (I and II) indicated equilibrium adsorption in less than 5 minutes. Composites I and II have MB removal efficiencies of 87% and 96.25%, respectively, and their estimated adsorption capacities at 20°C are 432 mg g-1 and 481 mg g-1. The adsorption process of MB onto Molybdenum dicarbonate-filter paper (composite I) suited well with the pseudo-first order and pseudo-second order kinetics and conformed to intraparticle diffusion model for Molybdenum dicarbonate-activated carbon composite (composite II). Adsorption of MB onto composite I aligned with both Freundlich model and Tempkin models due to higher values of correlation coefficients and fitted well with Langmiur model for composite II. Adsorption process was found to be endothermic and spontaneous in nature. The adsorption results revealed that these composites could be employed as effective adsorbents to remove dyes from industrial effluents.

The current research is focused on the need to find an economical adsorbent for the removal of heavy metals from industrial wastewater. The research was performed to assess the potential of a biocarbon generated from medicinal plant called Phyllanthus niruri (Phyllanthaceae) as an adsorbent in the removal of heavy metals from solution. Results from batch adsorption studies on the effect of pH, contact time, different concentration of Cu metal ions were used to estimate the optimum adsorption conditions. The obtained results showed that, the adsorption of the metal ions was dependent on adsorbent dosage, contact time and pH. The optimum adsorbent dosage, and pH, was found to be at 2.5 g and pH 4.4 respectively. The effective contact time was 150min at 30 0C. The study also showed that activated carbon produced from Phyllanthus Niruri biomass can be efficiently used as low cost alternative for removal of metal ions.

This study was aimed at determining the uptake of heavy metals (Cd, Pb, Ni, Fe and Zn) by plant (Talinum triangulare) if cultivated at some waste dumpsites in Uyo metropolis. Soil samples were taken within 0-15cm and plant samples were collected in triplicate and analysed using Atomic Absorption Spectrophotometer (AAS). Mean results obtained from the soil and plant samples indicated Fe to have the highest concentration (216.29±29.15mg/kg and 243.339±12.622mg/kg respectively) which is significantly higher than its control (124.00mg/kg and 78.375mg/kg respectively). Concentration of Pb in both dumpsite soil and plant samples were below detectable limit. These results when compared with the acceptable standard revealed that all the metal levels in both soil and plant samples were within the acceptable limits accept Cd in soil sample. Transfer factor for Fe was 1.13, while others were below 1. All the metals showed positive relationship except Cd (-0.60).

In this study, a hydrometallurgical treatment for valuable metals recovery from rinsing water of electroplating industries is reported. This water contains high contents of Copper, Nickel, Lead, Zinc and Chromium ions. Copper is recovered by leaching in hydrochloric acid solution. The effects of acid concentration, temperature and treatment time were investigated. Lead and Nickel are removed by adsorption onto activated carbon from artificial binary-component aqueous solutions. The effects of pH, time, temperature, and amount of adsorbent were investigated. Maximum Lead adsorption was obtained at pH 5.5-6 and 80?C for 30 min., while for Nickel at pH 7 and room temperature for 60 min.

Direct and rapid procedures for the electrothermal atomic absorption spectrophotometric determination of Bi, Sb, and Cd in different biological samples using a multi-element electrothermal atomic absorption spectrometer (Perkin-Elmer SIMAA 6000) are described. Two kinds of modifiers; Pd(NO3)2 + Mg(NO3)2 mixture modifier and Ir-permanent modifier were tested. For Seronorm urine, Lyphocheck urine, Bovine liver, Pig kidney, Pork liver, and Tea, the samples were diluted (1:4, v/v), (1:1, v/v), (1:9, v/v), (1:29, v/v), (1:3, v/v), (1:4, v/v), respectively, with 0.2% HNO3 which were then introduced directly into the furnace. The detection limits were 0.90-1.5 µg.l-1 for Bi, 0.79-1.3 µg.l-1 for Sb, and 0.01-0.025 µg.l-1 for Cd. The Characteristic masses were 73.3-88 pg for Bi, 46.3-67.7 pg for Sb, and 1.7-3.3 pg for Cd. The reliability of the procedures is checked by analyzing certified reference materials. A standard additions method was used to determine Bi, Sb, and Cd in the samples simultaneously. Results of analysis of standard reference materials were in agreement with certified values.

Cold extraction method was used extract the crude solvent extracts of leaf of Chrysophyllum albidum. The structural elucidation by spectroscopic methods (1H and 13C NMR) of a fraction of ethyl acetae extract of C. albidum yielded a new compound characterized as decyl heptadecanoate, C27H54O2. A similar compound Decyl-8-hydroxyl heptadecanoate has also been isolated from Ziziphus mauritiana leaves and has been synthesized via utilization of microwave energy using available starting compounds. Quantum chemical calculations have been carried out on the isolated compounds. Optimized geometry, IR frequencies, bond distances, bond angles and other parameters have been computationally determined for the isolated compound from the quantum chemical calculations using the GAUSSIAN 09 suite of programs. The experimentally measured and the computationally obtained IR frequencies are in good agreement.

In the present study fulvic acids (FAs) were first isolated from fulvic water (FW) and fulvic urea (SU) and then their quantification was accomplished by spectrophotometric methods. Aqueous solutions of FAs, FW and SU were made at pH 7.0 in the visible wavelength region at 25 oC using calibration curve method. Plot of absorbance Vs concentration of FAs at fixed wavelength (424 nm) was linear up to 120 mg L-1. The calculated FAs concentrations were in reasonable agreement with the gravimetric estimation made by solvent extraction.