Sequestering of Ni (II) and Co (II) from Aqueous Solution Using Spines of Bombax buonopozense as Low-Cost Adsorbent
Mustapha S.,
Dauda B. E. N.,
Ndamitso M. M.,
Amigun A. T.,
Mohammed U. M.,
Mathew J. T.
Issue:
Volume 5, Issue 5, September 2017
Pages:
89-97
Received:
29 January 2017
Accepted:
13 February 2017
Published:
11 August 2017
Abstract: The release of potentially toxic elements either by anthropogenic or industrial activities has deteriorated water quality rendering water bodies unsuitable. It was on this basis that readily available agricultural waste was used to treat simulated wastewater containing the potentially toxic element (Ni and Co). Adsorption studies of Co and Ni from aqueous solution were performed using spines of Bombax buonopozense (raw), carbon prepared from Bombax buonopozense (AC1) and activated carbon prepared from modification of spines of cotton silk tree (AC2). Batch adsorption techniques were carried out as a function of contact time, pH, initial concentration, temperature, and dosage. The respective optimum contact times required for adsorption Co and Ni were 90 min. Characterizations of adsorbents were carried out which include: bulk density, hardness, electrical conductivity, ash contents, percentage moisture, and yield. Fourier transform infra-red spectroscopy (FTIR) showed that functional groups in the sorbents were responsible for the adsorption process. The adsorption isotherms data were tested for Langmuir, Temkin and Freundlich equations. The pseudo-first-order, pseudo-second-order, Elovich and diffusion (intra-particle) models were investigated on the adsorption kinetic data. This could be as a result of ion exchange involved in the sequestration of metal ions by the adsorbents. Therefore, sorption using spines of Bombax buonopozense has been adjudged as one of the best tools for replacing conventional methods for the removal of these metals because of its efficiency, cost-effectiveness and the availability of the adsorbents.
Abstract: The release of potentially toxic elements either by anthropogenic or industrial activities has deteriorated water quality rendering water bodies unsuitable. It was on this basis that readily available agricultural waste was used to treat simulated wastewater containing the potentially toxic element (Ni and Co). Adsorption studies of Co and Ni from ...
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Establishing the Appropriate Conditions of Regeneration of Cataytic Reforming Pt/AL2O3 Catalyst
Paul Chidi Okonkwo,
Benjamin Aderemi,
Taiwo Olamide Olori
Issue:
Volume 5, Issue 5, September 2017
Pages:
98-110
Received:
30 July 2017
Accepted:
18 August 2017
Published:
2 November 2017
Abstract: Catalyst deactivation, the loss over time of catalytic activity and selectivity is a problem of great and continuing concern in the practice of industrial catalytic processes. Catalyst regeneration procedures for fixed-bed reforming units can vary widely. While all regeneration procedures share common elements, it is very common for the procedures to have evolved over years as unit configurations and throughputs have changed. Sub-optimal regeneration procedures can have a number of negative impacts on subsequent operation. In this study two samples of catalytic reforming Pt/Al2O3 catalysts were obtained from operating fixed bed semi regenerative reactors which has run for 10,000 and 14000 hours. These samples which have undergone deactivation in the course of the operations were regenerated under varying conditions of temperature, pressure and chlorination to establish the appropriate regeneration conditions. The progress and extent of regeneration were monitored using FTIR, SEM, XRD, GC-MS and XRF. The carbon content and effectiveness of the regenerated catalysts were determined and the values were compared with that of fresh catalysts. The regenerated catalysts showed 98 – 99.5% of the catalyst activity under the conditions of temperature and pressure of 500°C and 15psi respectively. The established conditions are to guide economic operations of such units which to realize high quality reformates and long life of the catalysts.
Abstract: Catalyst deactivation, the loss over time of catalytic activity and selectivity is a problem of great and continuing concern in the practice of industrial catalytic processes. Catalyst regeneration procedures for fixed-bed reforming units can vary widely. While all regeneration procedures share common elements, it is very common for the procedures ...
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Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica
Hamdy El-Didamony Ahmed,
Berry Abd El-Ghani Sabrah,
Saleh Abd El-Aleem Mohamed,
Nashwa Mohamed Mostafa
Issue:
Volume 5, Issue 5, September 2017
Pages:
111-121
Received:
31 August 2017
Accepted:
19 September 2017
Published:
3 November 2017
Abstract: Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the hydration characteristics and microstructure of cement pastes and mortars with and without nano-silica (NS) were studied. Blended cement mix containing 10 mass, % silica fume (SF) was prepared, then the cement mix was partially replaced by NS up 1.5 mass, %. The results show that, NS increases the water of consistency and final setting time The values of chemically combined water, free lime, bulk density and compressive strength prove that, NS up to 1% seems to be an effective mineral additive for blending with OPC to improve its chemical and engineering properties. This is mainly attributed to that; NS behaves not only as filler to improve microstructure, but also as pozzolanic material (PZM). The formation of more hydrated silicates in presence of NS was confirmed by XRD, DTA, IR and SEM examinations. At 1.5 mass, % NS, the density and strength are reduced but still higher than those of 0.0 and 0.5% NS. Also, the results indicate that, the substitution of blended cement mix (OPC+10% SF) with 1 mass, % NS gives a reasonable hydration characteristics and improved engineering properties more than those of 0.0 and 0.5% NS at all hydration ages up to 90 days. Therefore, this level of NS is suggested to be the most suitable replacement level.
Abstract: Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the ...
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