Cm Of Bed Height Research Articles

Studying the kinetics and removal mechanism of the methylene blue dye in a continuous adsorption process using prepared mesoporous materials

ABSTRACT This study investigated the removal of a typical organic pollutant methylene blue (MB) dye from wastewater by a prepared mesoporous SBA-15 adsorbent in a continuous adsorption system (fixed-bed column). The structural and textural properties of the SBA-15 adsorbent were determined using different characterization techniques. The adsorption of continuous system experiments assessed the bed height effect, initial concentration, and flow rate on a breakthrough curve. The kinetic constants and breakthrough curves were obtained using the Thomas and Yan models. The breakthrough results revealed that SBA-15 has an excellent adsorption efficiency for use in the continuous adsorption system. The findings explain that MB removal achieved the maximum uptake (84 mg/g) at 6 cm of bed height, 0.5 mL/min of flow rate, and 30 mg/L initial concentration of MB. SBA-15 can be efficiently regenerated by calcination and re-employed 5 times in a fixed-bed system without a significant loss in its adsorption capacity of MB from MB solutions. As a result, SBA-15 was determined as the appropriate media to be adsorbent for MB. This study suggests that the prepared SBA-15 is feasible to use effectively for MB removal from the wastewater.

Mitigation of oil spills from synthetic seawater using human hair – Experimentation, modeling and optimization

Oil spills are considered to be one of the worst catastrophes that occur in the marine environment and it is obligatory to remediate oil spills. The preset paper focuses on the adsorptive removal of oil spills from synthetic water using human hair, a potent natural adsorbent. Diesel was used as a representative of the spilled oils. Both batch and column studies were conducted and the maximum adsorptive capacity of hair was found to be 4.95 g/g. About 100% removal efficiency was obtained in column studies at 9 cm bed height with initial concentrations up to 20% (v/v). Equilibrium data were fitted to the Freundlich isotherm model and it was found that adsorption obeys the pseudo-second-order kinetic model. Artificial Neural Network (ANN) and Genetic Algorithm (GA) were employed for the modelling and optimization of the process. The adsorbent dose of 2.52 g with 13.45 min of contact time was found to be optimum to achieve maximum removal efficiency for batch study and 8.85 cm of bed height, 179.51 mL/h flow rate, and 15% of initial concentration were obtained as optimized values of column studies. The present study reinforces the utilization of human hair for the remediation of oil spills.

Remediation of perfluorooctanoic acid (PFOA) with nano ceramic clay: Synthesis, characterization, scale-up and regenerations

Perfluorooctanoic acid (PFOA) in the ecosystem, resulting from industrial effluent and water bodies, has attracted greater concern. An economical treatment is in demand to optimize the current issue. In this research work, Perfluorooctanoic Acid was treated from drinking water sources with nano-ceramic clay. The ceramic clay was synthesized and characterized with Fourier infrared transformation, scanning electron micrograph, transmission electron micrograph, x-ray diffraction, and thermal analysis. An adsorption process was performed in batch and continuous modes for the effective conditions for maximum removal. In batch mode 82 ± 12 nm ceramic clay particle size; 3.0 initial pH; 210 rpm agitation 1.2 mg/L PFOA concentration; 100 mg/L clay dosage; 27 °C temperature, and 20hrs experimental time shows maximum 99.15% adsorption. The experimental data is well fitted with kinetics, isotherms, and thermodynamics calculated data. In fixed bed, continuous column study 10 h treatment time, 10 cm of bed height, and 2 ml/min were adsorbed 99.99% of PFOA. The experimental data from the fixed bed adsorption equipment was correlated using a number of different mathematical models, including the Thomas, Adams-Bohart, Yoon-Nelson, and Clark models. Overall nano ceramic clay was found to potential adsorbent for Perfluorooctanoic acid removal.

Cobalt Biosorption in Fixed-Bed Column Using Greenhouse Crop Residue as Natural Sorbent

Intensive greenhouse agriculture annually produces large amounts of residues. The present work focused on the study of the dynamic adsorption of cobalt from aqueous solutions over a vegetal residue from intensive greenhouse cultivation. The influence of three operating variables, feed-flow rate, inlet concentration of cobalt and bed height, was analyzed. According to the results, the variable that particularly affected the percentage of cobalt adsorbed was the feed-flow rate. The results were also fitted to an adaptive neuro fuzzy system (ANFIS) model to predict cobalt adsorption from aqueous solutions and choose the most favorable operating conditions. Results were evaluated using root mean squared error (RMSE), coefficient of determination (R2) and other typical statistic factors as performance parameters. The experimental and model outputs displayed acceptable result for ANFIS, providing R2 values higher than 0.999 for both cobalt removal (%) and biosorption capacity (mg/g). In addition, the results showed that the best operating conditions to maximize the removal of cobalt were 4 mL/min of feed-flow rate, 25 mg/L of inlet concentration and 11.5 cm of bed-height.

Remarkable dynamic adsorption of Hg2+ ions on the magnetic MOF nanocomposite (CuNi-BTC@Fe3O4): Experimental and modeling using GA+CFD+ANFIS method

The magnetic bimetallic metal-organic framework (MOF) nanocomposite was fabricated using the facile preparation method for the removal of mercury ions in the fixed bed column. The several analyses including XRD, TEM, BET and VSM were also carried out to characterize the physico-chemical properties of the synthesized sample (CuNi-BTC@Fe3O4). The Langmuir model with a maximum adsorption capacity of 144.32 mg/g was fitted well with equilibrium data. The performance of the adsorption column was evaluated under the various operating conditions including length of bed (10, 15, 20 cm), flow rate of feed (10, 15, 20 ml/min) and initial concentration of mercury ions in the inlet (25, 50, 75 mg/l). The breakthrough time was measured to be about 581.1 min at the proper operating conditions including 15 cm of bed height, 50 mg/l of feed concentration and 10 ml/min of feed flow rate. The commercial models including Thomas and Yoon-Nelson were investigated for the determination of the adsorption behavior of Hg (II) in the adsorption column. The results indicated the good agreement between the experimental data and Yoon-Nelson model (R2 > 0.99). The combination model consisting of the unsteady computational fluid dynamics (CFD), an adaptive neuro-fuzzy inference (ANFIS) and genetic algorithm (GA) was developed to simulate the uptake of Hg (II) ions in dynamic bed. The employed ANFIS was also coded by using five layers to predict the source term of mass transfer equation as the most significant parameter of the modeling which must be calculated with high precision. The generated Gaussian membership functions i n the ANFIS model was optimized by applying GA. Finally, the CFD (the first order implicit) was linked with ANFIS to describe the dynasmic adsorption of mercury ions. The validation illustrated a good matching between the experimental data and the output of the combination model (R2 > 0.999).

Modeling of continuous adsorption of greywater pollutants onto sawdust activated carbon bed integrated with sand column

The real greywater samples collected from the IIT Roorkee hostel have been treated using waste biomass-derived activated carbon in continuous operation. The synthesized ZnCl2 impregnated sawdust activated carbon (SAC) has been used to remove the COD, BOD, and TDS concentration from the greywater. The SAC characterization through FESEM-EDX, BET, and FTIR has been performed. The initial concentration of COD, BOD, and TDS in greywater was 670, 275, and 1819.52 mg/L, respectively. The sand column was used to retain the larger suspended solids and dissolved organic matter up to a certain concentration. Sand column effluent with the concentration of 412, 180, and 1116.8 mg/L for COD, BOD, and TDS respectively, was drawn to the adsorption column for studying the influence of flow rate (5, 10, and 15 mL/min) at 15 cm of bed height and the effect of bed height (10 and 20 cm) at 10 mL/min of flow rate. At optimum condition of 10 mL/min flow rate and 10 cm of bed height, the observed adsorption capacities are 3904.62, 1967.3, and 14,936.92 mg/g for the removal of COD, BOD, and TDS, respectively. Further, to comprehend the behavior of the breakthrough curves eight mathematical models, namely, Bohart-Adams, Thomas, Wolborska, Yoon-Nelson, Log Gompertz, Gompertz, Dose-Response, and Bed Depth Service Time (BDST), have been tested.

Phosphonomethyl iminodiacetic acid functionalized metal organic framework supported PAN composite beads for selective removal of La(III) from wastewater: Adsorptive performance and column separation studies

The rare earth elements being toxic in nature are being accumulated in water bodies as their industrial usage is growing exponentially, thus their efficient separation holds an immense significance. Herein, ligand functionalized metal organic framework (MOF), Phosphonomethyl iminodiacetic acid coordinated at Fe-BTC, was synthesized post-synthetically and incorporated subsequently in polyacrylonitrile polymer to prepare the composite beads via nonsolvent induced-phase-inversion technique for selective adsorption of La(III) from the wastewater in batch and dynamic column mode. XPS NMR, and FTIR were used to establish the interaction between functionalized ligand and unsaturated metal nodes of MOF. The adsorption capacity was 232.5 mg/g and 77.51 mg/g at 298 K of the functionalized MOF and composite beads respectively. Adsorption kinetics followed a pseudo-second order rate equation, and isotherm indicated the best fitting with Langmuir model. The dynamic behavior of the adsorption column packed with MOF/Polymer beads was fairly described by the Thomas model. The breakthrough time of 23.2 h could be attained with 12 cm of bed height and 10 ml/min of flow rate. These MOF/Polymer beads shown the selectivity of La over transitional metals were recycled over 5 times with about 15% loss of adsorption capacity. The findings provide suggestive insights of the potential use of functionalized MOF towards the separation of the rare earth element.

Fixed-bed adsorption of tannery wastewater pollutants using bottom ash: An optimized process

This study investigates the reuse of bottom ash for the treatment of the tannery effluent in the fixed-bed column adsorption process. A parametric analysis of the process is carried out with conditions such as granulometry, adsorbent bed height and withdrawal flow rate, in order to evaluate optimal output and achieve optimum removal capacity of coloration. The results shows that, under 80 μm of granulometry, 15 mL.min−1 of flow rate and 11 cm of bed height, the discolouration rate reached maximum values close to 100%. Subsequently, we attempted to improve the quality of the final influent under controlled conditions through chain-continuous adsorption in a descending grain size system while measuring certain parameters such as electrical conductivity, pH, COD, absorbance, flow rate and volume at the outlet of each column. As a result, this technique allows for a reduction of 97.1% in COD. Finally, the Surface Response Method (RSM) is used to determine the main individual effects and to study the interaction of continuous adsorption process variables with a minimum number of experiments. Regression analysis with a 95% confidence level to confirm the significance of the model terms with a coefficient of determination (R2) of 0.9887 and a Fisher Value of 75.9.

Adsorption of Synthetic Dye by Betel Nuts Activated Carbon in a Fixed-bed Column, Experiments and Prediction of Breakthrough Curves

Wastewater produced from textile industry contains synthetic dye that couldn’t degrade naturally. The dye waste adsorbed in a continuous fixed-bed column by betel nuts activated carbon. The fixed-bed column had 60 cm of height and 2 inches of ID. The synthetic dye solution fed to the top of column with flow 10 ml/min. The column performance was evaluated with varying bed height in 5,10, and 15 cm. The outlet analyzed using UV-Vis spectrophotometer. The increased of bed height indicated longer of breakthrough time and column life. The 15 cm of bed height result column maximum capacity (qexp), % total removal, and total adsorbed dye solute (qtotal) in the amount of 21.99 mg/g, 68.17%, dan 3299.62 g respectively. The prediction of breakthrough curve has been done using kinetic adsorption study the of Thomas, Yoon-Nelson, Adam Bohart, and Bed Depth Service Time (BDST) model. The result of the experiment indicates the kinetic model of Thomas and Yoon-Nelson are the fit models, with the coefficients of regression (R2) are 0.98 and 0.95 at the bed heights of 10 and 5cm.

Computational fluid dynamics analysis of flow through immobilized catalyzed packed bed reactor for removal of 4-chlorophenol from wastewater

The computational fluid dynamics (CFD) simulation of the packed bed reactor (PBR) was carried out using ANSYS Fluent software. The various process parameters, such as inlet concentration of 4-chlorophenol (4-CP), flow rate, bed height, and porosity, were optimized to predict maximum biodegradation of 4-CP in immobilized catalyzed PBR. The geometrical mesh of the PBR was constructed using Gambit software, and a mesh size of 236995 was selected from the grid-independent study. A laminar flow model was used to understand the hydrodynamics as well as concentration profile of 4-CP inside the PBR using Fluent software. Through CFD, the effect of the flow rate, inlet concentration, and the bed height and porosity of the immobilized catalyst bed on the static pressure, mass imbalance, velocity, and stress-strain field inside the PBR was visualized. CFD simulation study predicted that maximum biodegradation of 4-CP was found in the presence of 500 mg/L of inlet concentration of 4-CP, 4 mL/min of flow rate, 18 cm of bed height and 0.375 of porosity. An experimental study was conducted for wastewater flow through the <i>B. subtilis MF447840.1</i> immobilized catalyzed PBR to remove the 4-CP in the laminar flow region. It was evident that CFD simulated results agreed well with experimental values.

Fixed-bed column system for Cd2+ uptake from aqueous solution by sodium- and thiourea-modified clinoptilolite-rich tuff

ABSTRACTTwo kinds of clinoptilolite-rich tuffs from the state of Sonora (Mexico), previously treated with NaCl solution and then modified with thiourea, were investigated to remove Cd2+ from aqueous solution in a fixed-bed column system. Experiments were conducted with a 30 mg L−1 Cd2+ solution at a pH value of 5 and three-bed heights of sodium- and thiourea-modified clinoptilolite-rich tuffs. The experimental data were examined with the bed depth service time model (BDST), the Thomas model, and a mass balance approach. According to the BDST model, the dynamic sorption capacity (No) for the thiourea-modified clinoptilolite-rich tuff was 0.0357 Kg L−1. This value corresponded to 1.2 times higher than that for sodium-modified clinoptilolite-rich tuff (0.0287 Kg L−1). The experimental data obtained for sodium- modified clinoptilolite-rich tuff (ZSGNa) with 3 cm of bed height, fitted to the Thomas model, with R2 = 0.9679 and Cd sorption capacity of 35.4 mg g−1, while for the thiourea-modified clinoptilolite-rich tuff (ZSGThio) with 4.5 cm of bed height, was 36.52 mg g−1 with R2 = 0.9368. The parameters calculated with the mass balance model describe a favourable process where the system with ZSGThio (6 cm bed height) had the best performance for sorption capacity up to the breakthrough point, qb = 22.35 mg g−1. The zeolite modified with thiourea exhibited higher capacity in Cd2+ removal than the one modified with NaCl, in the column with 6 cm of bed height. To investigate the mechanisms of removal of Cd2+ by the modified zeolites, Na⁺ was measured to determine the milliequivalents of cadmium removed.

Adsorption of Jumputan liquid waste by betel nuts activated carbon in a continuous fixed-bed adsorber

Jumputan is one of South Sumatera art crafts that increasingly produced by textile industries in the region. Dyeing and washing process are applied in jumputan production that will contribute to the increase of chemical content in waste water. This research will address the solution to this problem by investigating the waste water treatment using continuous adsorption process with activated carbon made from betel nuts as an adsorbent. Activated carbon was produced at carbonization temperature 500°C and activated by 0.5 M HCl and sized 18 mesh sieve. Adsorption was performed using Fixed-bed adsorber made from fiberglass with 100 cm height and 10 cm diameter. Jumputan liquid waste was fed from the top of the column at 58 mL/min. The height of bed was varied at 5, 15, 25 cm and sampling time was performed in 30, 60, 90, 120, 150 min to determine COD reduction. Optimum condition of this process is 25 cm of bed height and 150 min of sampling time that reduces COD value of waste water to 99.69%.

Optimization of capsaicin purification from Capsicum frutescens Linn. with column chromatography using Taguchi design

Capsaicin is a major capsaicinoids presented in hot chilies and peppers. It is widely used in pharmacology and clinical applications because of its properties such as anti-mutagen, anti-tumor and antioxidant. Therefore, the optimum capsaicinoids extraction was studied. Two different techniques, comparing with traditional soxhlet method, microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE), were used to extract the capsaicinoids from dried chilies (Capsicum frutescens Linn.). The electrical power (90–600W) and the extraction time (5–20min) were investigated for MAE while those of 5–30min were examined for UAE. The optimum method for capsaicinoids extraction was UAE which gave the highest amount of capsaicinoids at 4.01mg/g of dried chili. Consequently, the Taguchi's experiment design methodology was performed in order to identify the optimum capsaicin separation condition in column chromatography. Three factors including mobile phase ratio (ethanol:water), bed height and flow rate of mobile phase were analyzed. The mixed-level orthogonal array design, L16 (21×42) matrix was employed to access the capsaicin purity. The optimum conditions were 40% of ethanol as mobile phase, 25cm of bed height with the flow rate of mobile phase of 2.5ml/min. It was also found that the mobile phase ratio was the most important factor in capsaicin separation.

PEMBUATAN PUPUK ORGANIK CAIR DARI KOTORAN SAPI MENGGUNAKAN KOLOM FIXED BED SECARA KONTINYU

<p><strong><em>Abstract:</em></strong><em> Nowadays, organic fertilizer is more interesting than anorganic fertilizer, because it doesn’t cause soil degradation and the crops are healthier to be consumed. Manure is the most familiar as an organic fertilizer. This study dealt with producing of liquid organic fertilizer from cow manure in fixed bed column reactor. The reactor operated at 30 <sup>o</sup>C, 40 cmHg and 19.2 mL/s of solvent flowrate. The aim of this study was to find correlation between bed height of manure in column, particle size of manure, concentration of fertilizer and volumetric mass transfer coefficient </em>(<em>k<sub>c</sub>a</em>)<em>. The highest of k<sub>c</sub>a value was obtained at 25 cm of bed height, it was 0.0014 s<sup>-1</sup>. The result shows that bed height of manure is linier to k<sub>c</sub>a. On the other hand, particle size of manure doesn’t give much influence of k<sub>c</sub>a.</em></p><p><strong><em> </em></strong><strong><em>Keywords</em></strong><strong>:</strong><em> extraction, fixed bed, cow manure, liquid organic fertilizer, volumetric mass transfer </em><em>coefficient</em></p>

Development and utilization of aerobic granules for the palm oil mill (POM) wastewater treatment

The high COD and turbidity level of palm oil mill (POM) wastewater has been the driving force to find an efficient treatment system. In this work, biological and adsorption methods are integrated and used to treat the POM wastewater. In biological treatment, aerobic granules are developed and used in the sequencing batch reactor (SBR), whereas in adsorption treatment, the waste aerobic granules (WAG) are utilized as adsorbent. Response Surface Methodology (RSM) has been used to model and optimize the adsorption of biologically treated POM wastewater. Aerobic granules took 110 days to appear and the average diameter was 0.9 mm (with a maximum value of 3.1 mm). The aerobic granules are able to remove 88% of the influent COD at organic loading rate (OLR) of 3.0 kg COD/m 3 day. The increase of OLR to 6.0 kg COD/m 3 day did not affect the COD removal efficiency and the aerobic granules immediately responded to the OLR increase. The adsorption system revealed that the 21% of the remaining COD (of the biologically treated POM wastewater) and almost 99% of the turbidity were removed. At optimum point (3.28 cm of bed height and 2.13 ml/min flow rate), the amount of COD and turbidity removed are 21% and 96%, respectively.

Production of α-Galactosidase by Aspergillus oryzae through solid-state fermentation and its application in soymilk Galactooligosaccharide hydrolysis

α-Galactosidase was produced by Aspergillus oryzae on red gram plant waste-wheat bran based media in solid-state fermentation (SSF). Optimum temperature for α-galactosidase production was 35 0C and upto 4 cm of bed height of substrate had no inhibitory effect on enzyme production. Hydrolysis of galactooligosaccharides in soymilk was carried out by α-galactosidase. Optimum temperature and pH for the hydrolysis of raffinose and stachyose of soymilk were 55(0)C and 5.2-6.2, respectively. The enzymatic treatment for 3 h completely removed the raffinose oligosaccharides in soymilk. Crude extract also showed considerable amount of invertase activity.

Determination of kinetic and retention properties of cartridge and disk devices for solid-phase extraction.

The kinetic properties of cartridge and disk solid-phase extraction devices are determined by forced-flow liquid chromatography. Typical cartridges provide about 5-15 theoretical plates per cm of bed height and particle-loaded membranes provide about 4-9 theoretical plates for a 0.5-mm-thick membrane. It is shown that cartridge devices fail to provide their maximum trapping performance because of inadequate packing density and that the required packing density could be easily achieved in practice with particles of a standard size. The retention properties of common sorbents for extraction from water and air are characterized with the solvation parameter model. For predominantly aqueous solutions a favorable cavity term results in increased retention while polar interactions tend to reduce retention. Retention on porous polymer sorbents is more complicated because of their capacity to absorb significant amounts of the sample processing solvent resulting in solvent-dependent changes in retention properties. For trapping organic volatiles from air cavity formation and dispersion interactions are important, and in the case of Tenax its capacity for induction interactions is also significant.

Michael Tswett's columns: Facts and speculations

Although Michael Tswett is the originator of chromatography, little is known about the performance of his chromatographic systems. His descriptions of the separation of plant pigments are detailed but nevertheless difficult to interprete by today's chromatographic theory. By our own experiments with the system calcium carbonate/benzene it was found that the separation factor of chlorophyll a and b is approx. 1.6 which means that less than 100 theoretical plates are necessary for separation. Tswett's columns with 50 μm particles and 2–3 cm of bed height presumably exceeded this plate number. His separations could have been impaired by mass overload and by a volume flow rate which was two orders of magnitude faster than the optimum.