Removal of Chromium from Aqueous Solution using Multilayer-Mixed (Reduction/Sorption) Bed from Iron Scrap and Nutshells

In this research removal of chromium from an aqueous solution by multilayer-mixed (reduction/sorption) bed via scrap iron as zero valent iron and charred nutshell (walnut shell) as adsorber were studied. Both batch and continuous system were conducted. The batch system reveals that the adsorption process was of favorable type. Three models were used to describe the adsorption process. Freundlich model is matching well to the data with (R2=0.975). In the continuous system , two sets of experimental were considered, the first set (multilayer bed) conducted by fixing the characteristics of the scrap iron bed (bed height 0.2 cm, particle size 500 µm) and varying the walnut shell parameters, the optimum value of this set recorded as (bed height 2.5 cm, particle size250µm). While for the second set of experimental after fixing the optimum values of the walnut shell bed and varying the scrap iron bed characteristics, the optimum values were (height 1cm, particle size 500µm as filling). Also, the Mixed bed configuration were studied by conducting the optimum conditions for the previous experiment. it was found that at any certain time the mixed layer offers the maximum efficiency of removal rather than the multi-layer bed.

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FIXED-BED ADSORPTION OF AQUEOUS VANILLIN ONTO RESIN H103

IIUM Engineering Journal ◽

10.31436/iiumej.v18i2.804 ◽

2017 ◽

Vol 18 (2) ◽

pp. 94-104

Author(s):

Rozaimi Abu Samah

Keyword(s):

Aqueous Solution ◽

Flow Rate ◽

Adsorption Process ◽

Fixed Bed ◽

Maximum Adsorption Capacity ◽

Feed Flow Rate ◽

Fixed Bed Column ◽

Initial Concentration ◽

Bed Height ◽

Fixed Bed Adsorption

The main objective of this work was to design and model fixed bed adsorption column for the adsorption of vanillin from aqueous solution. Three parameters were evaluated for identifying the performance of vanillin adsorption in fixed-bed mode, which were bed height, vanillin initial concentration, and feed flow rate. The maximum adsorption capacity was increased more than threefold to 314.96 mg vanillin/g resin when the bed height was increased from 5 cm to 15 cm. Bohart-Adams model and Belter equation were used for designing fixed-bed column and predicting the performance of the adsorption process. A high value of determination coefficient (R2) of 0.9672 was obtained for the modelling of vanillin adsorption onto resin H103.

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Removal of amoxicillin from aqueous solution using sludge-based activated carbon modified by walnut shell and nano-titanium dioxide

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2020.162 ◽

2020 ◽

Author(s):

Xiaorong Kang ◽

Yali Liu ◽

Can Yang ◽

Han Cheng

Keyword(s):

Aqueous Solution ◽

Titanium Dioxide ◽

Activated Carbon ◽

Adsorption Process ◽

Removal Rate ◽

Total Pore Volume ◽

Raw Material ◽

Walnut Shell ◽

Order Kinetic ◽

Nano Titanium Dioxide

Abstract Dewatered municipal sludge was used as raw material to prepare activated carbon (SAC), and the SAC was modified by walnut shell and nano-titanium dioxide (MSAC). The results showed that the MSAC had a higher specific surface area (SBET) (279.147 m2/g) and total pore volume (VT) (0.324 cm3/g) than the SAC. Simultaneously, the functional groups such as C-O, C = O, and Ti-O-Ti on the surface of MSAC were enhanced due to modification. These physicochemical properties provided prerequisites for the diffusion and degradation of pollutants in MSAC. Furthermore, the MSAC was applied to adsorb amoxicillin (AMX) from aqueous solution, in batch experiments, the maximum removal rate (88.19%) was observed at an initial AMX concentration of 30 mg/L, MSAC dosage of 5.0 g/L, pH of 8, contact time of 180 min, and temperature of 25 °C. In addition, the adsorption process was well described by the Freundlich isotherm model and pseudo-second-order kinetic model, indicating that the adsorption of AMX onto MSAC was dominated by multilayer chemisorption. Also, the adsorption thermodynamics suggested that the adsorption process of AMX onto MSAC was endothermic, feasible and spontaneous.

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Cr(VI) biosorption: Effect of temperature, particle size and bed height

Revista Facultad de Ingeniería Universidad de Antioquia ◽

10.17533/udea.redin.20191149 ◽

2020 ◽

pp. 78-86

Author(s):

Candelaria Nahir Tejada-Tovar ◽

Angel Villabona-Ortíz ◽

Rodrigo Ortega Toro

Keyword(s):

Particle Size ◽

Fourier Transforms ◽

Continuous System ◽

Packed Bed ◽

Effect Of Temperature ◽

Infrared Spectrometry ◽

Packed Bed Column ◽

Chromium Vi ◽

Bed Height ◽

Vis Spectroscopy

The present work aimed to evaluate the effect of temperature, particle size and bed height of the chromium (VI) adsorption process using plantain peels in a continuous system. The experiment was carried out on a packed bed column, adjusting the feed temperature of the solution with a REX-C100 controller coupled to a type K thermocouple. The initial concentration of Cr (VI) was set at 100 ppm, the pH at 2 and the feed rate of 0.75 mL/s. The analyses were performed by UV-Vis spectroscopy using the colourimetric method of 1.5-diphenylcarbazide. The material was characterized by infrared spectrometry by Fourier Transforms (FTIR), from this analysis, it was determined that the OH and NH2 functional groups are the main responsible for the formation of complexes with the cations in solution. Also, it was established that only the particle size is statistically significant. According to the response surface analysis, the optimum conditions of the process were 353.15 K, a particle size of 0.819 mm and a bed height of 67.768 mm. From the thermodynamic study of the process, it is established that it is endothermic and the chemical adsorption prevails in it. The results obtained in the process modelling suggest that Dose-Response can be used reliably to scale the process.

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Removal of Methylene Blue from Aqueous Solution by Bone Char

Applied Sciences ◽

10.3390/app8101903 ◽

2018 ◽

Vol 8 (10) ◽

pp. 1903 ◽

Cited By ~ 7

Author(s):

Puqi Jia ◽

Hongwei Tan ◽

Kuiren Liu ◽

Wei Gao

Keyword(s):

Aqueous Solution ◽

Methylene Blue ◽

Particle Size ◽

Adsorption Process ◽

Removal Rate ◽

Isotherm Models ◽

Equilibration Time ◽

Bovine Bone ◽

Order Kinetic ◽

Bone Char

Bone char was prepared from bovine bone for the removal of methylene blue from aqueous solution. The effects of particle size, contact time, and adsorption temperature on the removal rate of methylene blue were investigated. It was found that bone char particle size had an insignificant effect. The equilibration time was found at approximately 80 min. The removal rate decreased with an increase in temperature. The intraparticle diffusion was the main rate-limiting step. The experimental data was analyzed by kinetic, isotherm, and thermodynamic equations. The results show that the pseudo-second-order kinetic model and Freundlich, Temkin, and Dubinin–Kaganer–Radushkevich isotherm models are true of the adsorption process. The spontaneous and exothermic ion-exchange adsorption process was certified by the negative values of free energy change and enthalpy change, and 13.29 kJ mol−1 of adsorption energy.

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Adsorption of Cu2+ from Aqueous Solution by Walnut Shell

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.1327 ◽

2013 ◽

Vol 864-867 ◽

pp. 1327-1332 ◽

Cited By ~ 1

Author(s):

Xiu Guo Lu ◽

Pei Pei Yan ◽

Xiao Fang Dang

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Metal Ions ◽

Adsorption Capacity ◽

Removal Rate ◽

Equilibrium Concentration ◽

Walnut Shell ◽

Adsorption Time ◽

Adsorbent Dosage ◽

Initial Ph

Walnut shell was used as adsorbent to remove Cu2+ metal ions from the simulated aqueous solution. The influence of factors, namely: particle size, initial pH, oscillation intensity, adsorbent dosage and adsorption time were investigated through single factor experiments.The results show that, the adsorption capacity reached the peak for Cu2+ in 25°C when the initial pH was 5, particle size was 1.25~1.6mm, adsorbent dosage was2.5g, oscillation speed reached 200r/min, and the adsorption time was 360min, all above leads the removal rate of Cu2+reached 75.7%, and the adsorption capacity of Cu2+ 0.702 mg/g. The pseudo-second-order model was fitted to describe the adsorption of Cu2+ , it was shown that adsorption rate for the metal ions in proportion to the square of the concentration.The equilibrium concentration of adsorption fitted well with Langmuir isotherm equation, the process of adsorption was single molecular layer adsorption.

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Fuels Desulphurisation by Adsorbtion on Fe / Bentonite

Revista de Chimie ◽

10.37358/rc.17.3.5483 ◽

2017 ◽

Vol 68 (3) ◽

pp. 483-486

Author(s):

Constantin Sorin Ion ◽

Mihaela Bombos ◽

Gabriel Vasilievici ◽

Dorin Bombos

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Pore Diameter ◽

Adsorption Process ◽

Continuous System ◽

Gas Oil ◽

Average Pore ◽

Atmospheric Distillation

Desulfurisation of atmospheric distillation gasoline and gas oil was performed by adsorption process on Fe/ bentonite. The adsorbent was characterized by determining the adsorption isotherms, specific surface area, pore volume and average pore diameter. Adsorption experiments of atmospheric distillation gasoline and gas oil were performed in continuous system at 280�320oC, 5 atm and volume hourly space velocities of 1�2 h-1. The efficiency of adsorption on Fe / bentonite was better at desulphurisation of gasoline versus gas oil.

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Utilization of Waste of Enzymes Biomass as Biosorbent for the Removal of Dyes from Aqueous Solution in Batch and Fluidized Bed Column

Revista de Chimie ◽

10.37358/rc.20.1.7804 ◽

2020 ◽

Vol 71 (1) ◽

pp. 1-12

Author(s):

Salman H. Abbas ◽

Younis M. Younis ◽

Mohammed K. Hussain ◽

Firas Hashim Kamar ◽

Gheorghe Nechifor ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solution ◽

Particle Size ◽

Adsorption Capacity ◽

Fluidized Bed ◽

Flow Rate ◽

Fungal Biomass ◽

Solution Flow Rate ◽

Maximum Adsorption Capacity ◽

Solution Flow

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.

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Comparative Bio-sorption of Cadmium and Nickel Ions from Aqueous Solution onto Fibers of Date Palm using Fluidized Bed Column

Revista de Chimie ◽

10.37358/rc.19.5.7160 ◽

2019 ◽

Vol 70 (5) ◽

pp. 1507-1512

Author(s):

Baker M. Abod ◽

Ramy Mohamed Jebir Al-Alawy ◽

Firas Hashim Kamar ◽

Gheorghe Nechifor

Keyword(s):

Aqueous Solution ◽

Heavy Metal ◽

Metal Ions ◽

Fluidized Bed ◽

Removal Efficiency ◽

Heavy Metal Ions ◽

Date Palm ◽

Operating Conditions ◽

Initial Concentration ◽

Bed Height

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

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Azithromycin nanosuspension preparation using evaporative precipitation into aqueous solution (EPAS) method and its comparative dissolution study

Current Pharmaceutical Analysis ◽

10.2174/1573412917999200909145745 ◽

2020 ◽

Vol 17 ◽

Author(s):

Mohammad Hossain Shariare ◽

Tonmoy Kumar Mondal ◽

Hani Alothaid ◽

Md. Didaruzzaman Sohel ◽

MD Wadud ◽

...

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Dissolution Rate ◽

Average Particle Size ◽

Scale Up ◽

Average Particle ◽

Total Drug ◽

Residual Solvent ◽

Dissolution Study ◽

Drug Content

Aim: EPAS (evaporative precipitation into aqueous solution) was used in the current studies to prepare azithromycin nanosuspensions and investigate the physicochemical characteristics for the nanosuspension batches with the aim of enhancing the dissolution rate of the nanopreparation to improve bioavailability. Methods: EPAS method used in this study for preparing azithromycin nanosuspension was achieved through developing an in-house instrumentation method. Particle size distribution was measured using Zetasizer Nano S without sample dilution. Dissolved azithromycin nanosuspensions were also compared with raw azithromycin powder and commercially available products. Total drug content of nanosuspension batches were measured using an Ultra-Performance Liquid Chromatography (UPLC) system with Photodiode Array (PDA) detector while residual solvent was measured using gas chromatography (GC). Results: The average particle size of azithromycin nanosuspension was 447.2 nm and total drug content was measured to be 97.81% upon recovery. Dissolution study data showed significant increase in dissolution rate for nanosuspension batch when compared to raw azithromycin and commercial version (microsuspension). The residual solvent found for azithromycin nanosuspension is 0.000098023 mg/ mL or 98.023 ppb. Conclusion: EPAS was successfully used to prepare azithromycin nanoparticles that exhibited significantly enhanced dissolution rate. Further studies are required to scale up the process and determine long term stability of the nanoparticles.

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Batch Precipitation of Lead Iodide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941301 ◽

1994 ◽

Vol 59 (6) ◽

pp. 1301-1304

Author(s):

Jaroslav Nývlt ◽

Stanislav Žáček

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Crystal Size ◽

Lead Nitrate ◽

Lead Iodide ◽

Constant Rate ◽

Mean Size ◽

The Mean

Lead iodide was precipitated by a procedure in which an aqueous solution of potassium iodide at a concentration of 0.03, 0.10 or 0.20 mol l-1 was stirred while an aqueous solution of lead nitrate at one-half concentration was added at a constant rate. The mean size of the PbI2 crystals was determined by evaluating the particle size distribution, which was measured sedimentometrically. The dependence of the mean crystal size on the duration of the experiment exhibited a minimum for any of the concentrations applied. The reason for this is discussed.

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