Open Access Original Research Article

A Comparative Analysis of Fractionation of Potassium in Soils from Some Refuse Dumpsites in Benin City Nigeria

P. O. Oviasogie, D. Okoro, P. T. Ikyaahemba

International Research Journal of Pure and Applied Chemistry, Page 1-11
DOI: 10.9734/irjpac/2021/v22i430399

A study on potassium dynamics and fractionation was carried out in Benin City to determine the amount and distribution of k fraction in soil samples collected from different refuse dumpsites. The sand, silt and clay contents of the dumpsites soils varied from 83.3 to 95.3, 0.60 to 3.35 and 2.55 to 15.10%, respectively. Soils were dominantly sandy with textural classes varying from sand to loamy sand down at depth. The result revealed that the water-soluble k and Exchangeable k range from 163.8 to 643.4 mg/kg in surface soils and 271.1 to 319.8 mg/kg in sub-surface in Benin-Onitsha Bypass and Benin-Warri Bypass. The difficult exchangeable k content ranged from 93.6 to 483.6 mg/kg and 50.1 to 467.9 mg/kg .in the surface and sub-surface of the dumpsites; K content was highest in the subsurface soils than in surface soils due to high deposition of refuse from surface soils within the dumpsites. In general, distribution of K forms decreased in the order reserved K > fixed > water-soluble > Exchangeable K, Structural K > Diff. Exch. K as well as the mobility factor for each of the refuse dumpsite investigated. Similarly, the amount of the various forms of k extracted decreased as the soil pH decreased. The soil samples collected far away from the dumpsites have lower concentrations of k forms compared to those from the vicinity of the dumpsites. This shows that the waste dumps had higher concentration of elements, thereby interacting with the soil and enhance their dominance within the dumpsites. The particle size fraction of the refuse dump suggests the need for consideration of active soil portions for sustainable K management of the environment.

Open Access Original Research Article

Analysis of Cultural and Pathogenic Diversity in Bipolaris sorokiniana Causing Spot Blotch of Bread Wheat in North India

Amit Chauhan, Lokesh K. Mishra, R. V. Singh, Ramji Singh

International Research Journal of Pure and Applied Chemistry, Page 12-22
DOI: 10.9734/irjpac/2021/v22i430400

Present study was conducted to analyse the cultural and pathogenic diversity in different isolates of Bipolaris sorokiniana the causal organism of spot blotch in bread wheat. Six isolates of Biplorais sorokiniana (BS-F-5, BS-D-2, BS-K,4, BS-DWR-K-1, BS-V-6, and BS-P-3) were evaluated simultaneously for cultural and pathogenic variability on the basis of diverse characteristics against seven different genotypes of wheat grown in the region viz: BOW’S’, HS 375, HUW 234, PBW 343, PBW 443, K9107 and A9-30-1. The results indicated that isolates varied significantly among themselves for all the characters analysed. The isolate BS-F-5 exhibited the maximum colony diameter, maximum average dimension (length and width) of conidiophore, maximum number of septa in conidiophore and conidia. Variations were also observed in texture of the colony. Among the seven genotypes tested against six isolates, BOW’S’ showed resistance against three isolates (BS-D-2, BS-K,4, BS-DWR-K-1) and genotype A-9-30-1 showed high susceptibility against all isolates except BS-D-2. The isolates BS-F-5 and BS-P-3 exhibited maximum pathogenic virulence among the isolates analysed in the present investigation.

Open Access Original Research Article

Electrooxidation of the Paracetamol on Boron Doped Diamond Anode Modified by Gold Particles

Kambiré Ollo, Alloko Kouamé Serge Pacome, Pohan Lemeyonouin Aliou Guillaume, Koffi Konan Sylvestre, Ouattara Lassiné

International Research Journal of Pure and Applied Chemistry, Page 23-35
DOI: 10.9734/irjpac/2021/v22i430401

The environment pollution, in particular that of the aquatic environment, by wastewater is a reality because it is discharged for the most part without treatment. The presence of pharmaceutical pollutants such as paracetamol in these waters can constitute a risk to human health. The objective of this work is to study the electrochemical oxidation of paracetamol using cyclic voltammetry on the boron doped diamond (BDD) anode and boron doped diamond modified by gold particles (Au-BDD) anode. The Au-BDD electrode was obtained by modifying the surface of BDD with gold particles. This was done by electrodeposition (chronoamperometry) in 0.5 M HAuCl4 and 0.1 M H2SO4 using a three pulse nucleation and growth process. Physical characterization with Scanning Electron Microscopy coupled with Dispersive Energy spectroscopy has shown that the Au-BDD surface presents asperities with the presence of microparticles and nanoparticles. The electrochemical characterization made in three electrolytic solutions (H2SO4, NaOH and KClO4) showed that Au-BDD has a high electroactivity domain than that of BDD. The study of the Benzoquinone-hydroquinone redox couple has shown a quasi-reversible character of these two anodes. It also revealed that Au-BDD has a more accentuated metallic character than BDD. The voltammetric measurements made it possible to show that the paracetamol oxidation is limited by the transport of material on each anode. This oxidation is characterized by the presence of an anodic peak in the support electrolytes stability domain. The paracetamol oxidation is rapid on Au-BDD than on BDD in the various medium explored, thus showing that Au-BDD is more efficient than BDD for the paracetamol oxidation by electrochemical means.

Open Access Original Research Article

Synthesis and Characterization of Rice Husk Biochar and its Application in the Adsorption Studies of Lead and Copper

Alice Ndekei, Muigai- Gitita, Njagi Njomo, Damaris Mbui

International Research Journal of Pure and Applied Chemistry, Page 36-50
DOI: 10.9734/irjpac/2021/v22i430402

The present study aimed to use chemically activated rice husk biochar as an adsorbent for the removal of heavy metals from an aqueous solution. A series of the Rice husk biochar (RHB) samples were produced at different temperatures, as follows: 300, 400, 500, 600, and 700℃ for 2 hours each through pyrolysis process in Dalhan Scientific Muffle Furnace. The chemically treated rice husk biochar synthesized at 500℃ was used as potential char for removal of Cu(II) and Pb(II) from aqueous solutions. The sorption of these metal ions from an aqueous solution was determined after adsorption using Flame Atomic Absorption Spectrophotometry (AAS). The Shimadzu IR Affinity Fourier Transform Infra-Red Spectroscopy (FT-IR) was used for the characterization of rice husk char and it revealed the presence of OH, C=O, and COO- bonds which are responsible for heavy metal ions adsorption through chemisorption. The effect of adsorption parameters was determined that is; pyrolysis temperature which was found to be 500℃, the optimal contact time for the metal ions Cu (II) and Pb (II) was found to be 60 minutes, the optimum dosage was 0.250 g and optimum initial concentration was 2 mg/l.  The kinetics were tested against pseudo-first order and pseudo-second order model as well Langmuir and Freundlich isotherms. Cu(II), adsorption process followed Pseudo-second order kinetics with regression coefficient (R2) 0.9942 and Langmuir isotherm model with R2 0.9895. For Pb(II), adsorption capacity followed Pseudo-second order kinetics with regression coefficient (R2) 0.99991 and Freundlich isotherm model with R2 0.96675 optimum equilibrium adsorption capacity of 0.5274 mg/g.