Archives

Volume 6 Number 2 June 2021

Synthesis and Characterization of Novel -Type Zirconium Phosphate-Crystalline Cerium Phosphate/ Polyaniline, Polyindole, Polycarbazole, Polyaniline-co-Polyindole, and Polyaniline-co-Polycarbazole Composites


Authors: S. K. Shakshooki ; F. A. El-Akari ; Najat A. Abozaid
Pages: 45-59
DOI: doi.org/10.32861/ajc.62.45.59
Abstract
-Type zirconium phosphate,-Zr(HPO4)2-.1.77H2O (-ZrP), crystalline cerium phosphate, Ce(HPO4)2.1.33 H2O (CePc), and [-Zr(HPO4)2]0.30 [Ce (HPO4)2]0.70 .2H2O composite were prepared and characterized by chemical, XRD, TGA, FT-IR and scanning electron microscopy(SEM). [-Zr(HPO4)2]0.30[Ce(HPO4)2]0.70/polyaniline, polyindole, polycarbazole, polyaniline-co-polyindole,  polyaniline-co-polycarbazole composites  were prepared via in-situ chemical oxidation of the monomers aniline, indole , carbazole, and (1:1moler ratio) of co-monomers aniline-indole, aniline- carbazole, respectively, that was promoted by the reduction of part of Ce(IV) ions present in the inorganic matrix. A possible explanation is part of CePc is attacked by the monomers, and the co-monomers, respectively, converted to cerium (III) orthophosphate (CePO4). The resultant novel composites were characterized by elemental (C,H,N) analysis, FT-IR, and (SEM). From elemental (C,H,N) analysis ,the amount of organic materials present in  [-Zr(HPO4)2]0.30 [Ce (HPO4)2]0.70/ polyaniline, polyindole, polycarbazole composites were (23.44, 5.24 and   33.02 % in wt. ), respectively. The amount of resultant copolymers were (Pani 5.92, PIn 7.48 % in wt) and (Pani 1.42, PCz 2.48 % in wt ) These composites can be considered as novel conducting inorganic-organic composites, ion exchangers , solid acid catalysts and sensors.

Efficacy of Chitosan as a Coagulant Aid to Alum Precipitation of Congo Red In Wastewater


Authors: Adelagun Ruth Olubukola Ajoke ; Magomya Asabe Mercy ; Kamba Emmanuel Alhassan
Pages: 37-44
DOI: doi.org/10.32861/ajc.62.37.44
Abstract
The use of chitosan prepared from prawn shells as coagulant aid for congo red (CR) dye removal from wastewater was investigated in this study. Characterisation of the prepared chitosan samples showed characteristics similar to commercially available ones. The coagulation – flocculation experiment was carried out using the jar test procedure. Both chitosan and alum were used separately for the dye precipitation and then combined together. The usage of alum alone showed no precipitating effect on the CR dye molecule, while chitosan was able to considerably reduce the concentration of the dye in solution. When chitosan was used as a coagulant aid in the alum precipitation, the amount (%) of dye removed increased greatly. Optimization of the process via study of effect of pH and flocculation time at optimum alum – chitosan combination indicated that pH 4-5 and settling time of 40 min were suitable conditions for maximum decolourisation of CR dye wastewater with about 98% efficiency. Moreover, study of settling characteristics of the sludge produced from the alum-chitosan synergy was better than that produced from either of them alone. Also, occurrence of redispersion and restabilization of the precipitate was not encountered.

Temporal (Monthly) Distribution and Variation of Total Petroleum Hydrocarbons Content in the Water and Sediments from Orashi River, Engenni, Rivers State, Nigeria


Authors: Edori E. S. ; Edori O. S.
Pages: 28-36
DOI: doi.org/10.32861/ajc.62.28.36
Abstract
The total petroleum hydrocarbons content of the surface water and the sediments from the Orashi River were investigated between December 2019 and June 2020 at two months intervals to find out the level of contamination of the river. The total petroleum hydrocarbons were determined by GC-FID using Agilent 5890N, after following due laboratory procedures of sample pretreatment and clean-up. The results recorded from the surface water were December, 5.844±1.231 mg/L; February, 8.767±2.501 mg/L, April, 16.886±3.157 mg/L and June, 7.271±1.110 mg/L. Variation in concentration showed that April > February > June > December. Results recorded in the sediments were December, 39.8427±13.5 mg/Kg; February, 29.5322±5.301 mg/Kg; April, 50.5040±16.813 mg/Kg and June; 16.6545±3.35 mg/Kg. The variation in concentration showed that April > December > February > June. The variations observed in of total petroleum hydrocarbons content in the river indicated that the contamination source was primarily anthropogenic. It is therefore recommended that effective measures and adequate steps be taken by the government to mitigate the effect that may result from the accumulation of the total petroleum hydrocarbons in the river and on the aquatic inhabitants and man who depends on the river for daily living.