Equilibrium, kinetic and thermodynamic studies of the adsorption of acidic dye onto bagasse fly ash

Mona A. Shouman,Nady A. Fathy,Sahar M. El-Khouly,Amina A. Attia 한국탄소학회 2011 Carbon Letters Vol.12 No.3

Bagasse fly ash (BFA) is one of the important wastes generated in the sugar industry; it has been studied as a prospective low-cost adsorbent in the removal of congo red (CR) from aqueous solutions. Chemical treatment with H2O2 was applied in order to modify the adsorbability of the raw BFA. Batch studies were performed to evaluate the influence of various experimental parameters such as dye solution pH, contact time, adsorbent dose, and temperature. Both the adsorbents were characterized by Fourier-transform infrared spectrometer, energy-dispersive X-ray spectrophotometer and nitrogen adsorption at 77 K. Equilibrium isotherms for the adsorption of CR were analyzed by Langmuir, Freundlich and Temkin models using non-linear regression technique. Intraparticle diffusion seems to control the CR removal process. The obtained experimental data can be well described by Langmuir and also followed second order kinetic models. The calculated thermodynamic parameters indicate the feasibility of the adsorption process for the studied adsorbents. The results indicate that BFA can be efficiently used for the treatment of waste water containing dyes.

Sorption of $Pb^{2+}$ Ions on to Activated Carbons Prepared from Olive Stones

Attia, Amina. A.,Shouman, Mona. A.,El-Nabarawy, Th. Korean Carbon Society 2005 Carbon Letters Vol.6 No.3

The carbon sample "O", phosphoric acid-activated carbon "OP", zinc chloride-activated carbon "OZ", and two steam activated carbons "OS" and "OS2" with different burn-off of 25% and 58% respectively, were prepared from olive stones. The textural properties were determined from the results of nitrogen adsorption at 77 K and by analyzing these results through the application of different adsorption models. The chemistry of the carbon surfaces was determined from the base neutralization capacities, acid neutralization capacity and surface pH. The sorption of $Pb^{2+}$ ions on to the carbons prepared was followed under dynamic and equilibrium conditions. The differences between the values of the textural parameters were attributed to the inapplicability of some adsorption models and to the heterogeneity of the microporous carbons. The sorption of $Pb^{2+}$ ions is favored on carbon and activated carbons. However, chemically activated carbons are more effective compared with steam-activated ones. The sorption of $Pb^{2+}$ ions were related to the chemistry of the surface rather than to the textural properties.

A Proposed Method for Ship Safety Enhancement After Flooding

Nourhan I. GHONEIM,Mohamed SHOUMAN,Kambiz MOKHTARI 국제이네비해양경제학회 2020 International Journal of e-Navigation and Maritime Vol.15 No.1

Bulk carrier ship type is one of the three dominant types of merchant vessels along with container ships and tankers. Recently, in terms of tonnage, bulk carriers constitute about the world's fleet third. The stuff materials indigence such as grains, fertilizers, ores, etc. Since the turn of the millennium, the number has increased considerably. Recently, a growing variance in bulk cargo which has transported by sea, represents now a large part of international commercial exchange shipped by sea. Every year there are huge number tons of cargoes like steel, coals, livestock feed, copper and minerals that are transported by sea in bulk. While most of those shipments are made without accidents, a number of serious injuries have occurred which have resulted not only in the ship's loss, but also in lives loss. In this paper, there is an existing bulk carrier vessel, a computational case study, is made to investigate the different loading conditions effects and bulk cargoes’ types on ship’s stability, in case of damaged conditions, in addition to the effect on the ship’s hull longitudinal strength. A proposed method is suggested to improve the level of safety of the ship past flooding by the usage of air bag (cushion). The candidate vessel consists of two cargo holds. In this paper there are three investigated damage scenarios, the first one is checking the stability in case of damage of cargo hold No.1. The second one is checking the stability in case of damage of cargo hold No.2 and the third scenario is checking the stability in case of flooding of both of the two cargo holds. There’s a modelling software, Auto Ship, is used here to model the vessel, simulate the different scenarios and to run the stability code to check the stability criteria. Finally, after performing the above mentioned three damage scenarios, the result was that the ship will still float in case of scenario one or two but in case of the third scenario, it will sink. So, this study has suggested a way to keep the vessel floating in case of the third scenario until reaching the nearest port without sinking. This proposed method is by using air cushions to open directly in case of existing alarm in the bulk carrier work to fill all the space inside the cargo hold instead of filling with the water.

Removal of Cu (II) and Cd (II) Ions Onto Water Hyacinth Based Carbonaceous Materials

Amina, A. Attia,Shouman, Mona.A.,Khedr, S.A.,El-Nabarawy, Th. Korean Carbon Society 2006 Carbon Letters Vol.7 No.4

Treatment of water hyacinth with sulphuric acid produces carbonaceous materials that have been used to remove Cu(II) and Cd (II) ions from aqueous solutions. Untreated water hyacinth was also used for the subject of comparison. The textural properties of the carbonaceous materials were determined from nitrogen adsorption at 77 K. The optimum pH for the sorption of Cu (II) and Cd (II) ions on the investigated sorbents was determined. Dynamic adsorption measurements have been taken at 298 K whereas equilibrium measurements were carried out at 298, 313 and 323 K. The adsorption of nitrogen at 77 K on the untreated sample was too low and the surface areas of the treated samples 2, 3 and 4 were found between $70-208\;m^2/g$. The total pore volumes of these samples which were determined for the carbonaceous materials investigated were found to be 0.076-0.140 ml/g. The kinetic adsorption data of Cu (II) and Cd(II) were applicable to both pseudo - first and pseudo-second order but fit more the latter order. The equilibrium adsorption data were found to fit Freundlich and Langmiur equations. The values of DG, DH and DS are all negative indicating the feasibility and the spontaneous nature of the sorption of Cu (II) and Cd (II) ions by the sorbents investigated.

Sorption of Pb2+ Ions on to Activated Carbons Prepared from Olive Stones

Amina. A. Attia,Mona. A. Shouman,Th. El-Nabarawy 한국탄소학회 2005 Carbon Letters Vol.6 No.3

The carbon sample "O", phosphoric acid-activated carbon "OP", zinc chloride-activated carbon "OZ", and two steam activated carbons "OS" and "OS2" with different burn-off of 25% and 58% respectively, were prepared from olive stones. The textural properties were determined from the results of nitrogen adsorption at 77 K and by analyzing these results through the application of different adsorption models. The chemistry of the carbon surfaces was determined from the base neutralization capacities, acid neutralization capacity and surface pH. The sorption of Pb2+ ions on to the carbons prepared was followed under dynamic and equilibrium conditions. The differences between the values of the textural parameters were attributed to the inapplicability of some adsorption models and to the heterogeneity of the microporous carbons. The sorption of Pb2+ ions is favored on carbon and activated carbons. However, chemically activated carbons are more effective compared with steam-activated ones. The sorption of Pb2+ ions were related to the chemistry of the surface rather than to the textural properties.

Removal of Cu (II) and Cd (II) Ions Onto Water Hyacinth Based Carbonaceous Materials

A. Attia Amina,Mona.A. Shouman,S.A. Khedr,Th. El-Nabarawy 한국탄소학회 2006 Carbon Letters Vol.7 No.4

Treatment of water hyacinth with sulphuric acid produces carbonaceous materials that have been used to remove Cu(II) and Cd (II) ions from aqueous solutions. Untreated water hyacinth was also used for the subject of comparison. The textural properties of the carbonaceous materials were determined from nitrogen adsorption at 77 K. The optimum pH for the sorption of Cu (II) and Cd (II) ions on the investigated sorbents was determined. Dynamic adsorption measurements have been taken at 298 K whereas equilibrium measurements were carried out at 298, 313 and 323 K. The adsorption of nitrogen at 77 K on the untreated sample was too low and the surface areas of the treated samples 2, 3 and 4 were found between 70-208 m2/g. The total pore volumes of these samples which were determined for the carbonaceous materials investigated were found to be 0.076-0.140 ml/g. The kinetic adsorption data of Cu (II) and Cd(II) were applicable to both pseudo - first and pseudo-second order but fit more the latter order. The equilibrium adsorption data were found to fit Freundlich and Langmiur equations. The values of DG, DH and DS are all negative indicating the feasibility and the spontaneous nature of the sorption of Cu (II) and Cd (II) ions by the sorbents investigated.

Sorption of Chromium Ions from Aqueous Solution onto Chemically Activated Carbons Developed from Maize Cobs

A.M. Youssef,Th. El-Nabarawy,Mona A. Shouman,S.A. Khedr 한국탄소학회 2008 Carbon Letters Vol.9 No.4

Chemically activated carbons were prepared from maize cobs, using phosphoric acid of variable concentration. The textural parameters of the activated carbons were determined from the nitrogen adsorption isotherms measured at 77 K. The chemistry of the carbon surface was determined by measuring the surface pH, the pHPZC and the concentration of the carbon - oxygen groups of the acid type on the carbon surface. Kinetics of Cr(VI) sorption/reduction was investigated at 303 K. Two processes were investigated in terms of kinetics and equilibrium namely; Cr(VI) removal and chromium sorption were studied at various initial pH (1-7). Removal of Cr(VI) shows a maximum at pH 2.5. At pH<2.5, sorption decreases because of the proton competition with evolved Cr(III) for ion exchange sites. The decrease of sorption at pH>2.5 is due to proton insufficiency and to the decrease of the extent of Cr(VI) reduction. The chemistry of the surface of activated carbon is an important factor in determining its adsorption capacity from aqueous solutions particularly when the sorption process involves ion exchange.

Processing and fundamental characterization of carbon fibers and cellulose nanocrystals derived from bagasse

Amina Abdel Meguid Attia,Maged Shafik Antonious,Mona Abdel Hamid Shouman,Ahmed Ali Ahmed Nada,Khadiga Mohamed Abas 한국탄소학회 2019 Carbon Letters Vol.29 No.2

Lignocellulosic materials such as agricultural residues have been identified as potential sustainable sources that can replace petroleum-based polymers. This study focused on the conversion of lignin extracted from bagasse to carbon fiber (CF) and cellulose nanocrystal (CNC). The highest extraction of lignin yield was achieved at 100 °C using 10% NaOH for 12 h. Carbon fibers were obtained by electro-spinning of bagasse lignin blended with polyvinyl alcohol (PVA) (11 wt/v %) followed by thermo-stabilization (250 °C) in an oxidizing atmosphere and further carbonization in an inert atmosphere (850 °C). Conventional hydrolysis process was used to extract cellulose nanocrystal from bagasse pulp. Morphological (scanning electron microscopy, SEM), spectral (Fourier transform infrared, FTIR) spectroscopy, elemental analysis, thermal characterization and surface area measurements have been carried out. Figures originated by SEM showed that CF ranges from 145 to 204 nm, while stabilized bagasse cellulose nanocrystal (SCNC) appeared as rod-shape like structure in the range of length 600–800 nm and diameter 5.33–19 μm. Characterization results revealed that CF exhibits microporous structure, while bagasse lignin and SCNC display mesoporous structure. In addition, the results proved that SCNC exhibits a percentage removal 71.56% for methylene blue dye in an aqueous solution.