Column Adsorption Method Research Articles

Harnessing the potential of zinc oxide nanoparticles from Strychnos potatorum seeds impregnated with activated carbon for an effective removal of fluoride in deep soil water

Abstract Fluoride (F−) contamination in global water sources is a growing concern, prompting the need for innovative solutions. This explores a novel method using zinc oxide nanoparticle-activated carbon (ZnO-NP/AC) composite for efficient fluoride removal from deep soil water, aiming to evaluate its effectiveness in attracting fluoride contaminants. The focus is on treatment of water sample collected from Dharmapuri, Tamil Nadu, using green synthesis method for ZnO-NP/AC column filter. Employed an exclusive column adsorption method, investigated on physiochemical parameters in water before and after running the column. Fluoride concentration and TDS where significantly harnessed in water after running the green synthesis composite column filter. Characterization of green synthesized nanoparticles of Strychnos potatorum seed powder synthesis with ZnO NPs. Green synthesis successes were confirmed in two ways; one way is UV-visible spectrophotometer technique in depth quantity peak and another one is graphically peak from SEM, density and crystalline structure in XRD techniques. Column composite with S.potatorum ZnO-AC NPs has removed fluoride efficiently (80.5%) at range of 20 g/L for a contact time of 60 minutes, surpassing World health organization (WHO) guidelines for safe drinking water. In conclusion ZnO-AC NPs composite is a sustainable and cost-effective method for effective removal of fluoride contaminants from deep soil water, addressing a pressing global issue.

Successful removal of fluoride from aqueous environment using Al(OH)3@AC: column studies and breakthrough curve modeling.

In this study, we discuss the removal of fluoride from water through column adsorption methods using Al(OH)3@AC as a functional granular activated carbon. The height of the bed, fluoride concentration, and flow rate are the experimental factors used to obtain the breakthrough curves. As the flow rate increased, the breakthrough and saturation times decreased. The analysis of simplified column models, such as the Adams-Bohart, Thomas, and Yoon-Nelson models, revealed that the Clark model best described the adsorption process when fitting the experimental data. The obtained breakthrough curves agreed with the corresponding experimental data. The highest capacity for adsorption obtained during the column procedure was found to be 41.84 mg g-1 with a bed height of 3 cm, an initial fluoride concentration of 10 mg L-1 and a flow rate of 7.5 mL min-1.

Utilization of Multivariate Optimization for Preconcentration and Determination of Lead in Different Water and Food Samples Using Functionalized Activated Carbon

In this study, apricot-pit-based activated carbon was functionalized and used as a sorbent for the preconcentration of lead (Pb2+) in different water and food samples. The activated sorbent was modified with ethylenediaminetetraacetic acid (EDTA) to enhance its selectivity for the efficient removal of Pb2+ ions. The modified activated sorbent was characterized using FTIR, an SEM, BET, and TGA. The column adsorption method was used to study the adsorption capacity of synthesized and modified activated carbon and analyzed using atomic absorption spectrophotometry. A multivariate procedure, i.e., Plackett–Burman design (PBD) and central composite design (CCD), was studied for optimizing the adsorption process, which allows the optimization of multiple variables at the same time. An interference study was conducted to ascertain the selectivity of the developed method. The developed method was validated by assessing certified reference materials and additional standards for Pb2+ detection in real samples. To assess the precision of the proposed procedure, repeatability (RSDr) and reproducibility (RSDR) were calculated, which were determined to be <3.0 (n = 7) and <7.5 (n = 15), respectively. The obtained results revealed that the modified AC is a suitable and efficient sorbent for the preconcentration of Pb2+ in real water and food samples.

Insights into the adsorption of lead ions by Mg-Al LDH doped activated carbon composites: Implications for fixed bed column and batch applications

In this study, we developed granular activated carbon-doped Mg-Al LDH composites (MgAl@AC) with an Mg:Al molar ratio of 3:1 using the co-precipitation method. The MgAl@AC was characterized using FE-SEM, BET-SA, TGA, XRD, and FT-IR, before and after lead adsorption. Through fixed-bed column and batch adsorption methods, we evaluated the impact of pH, adsorbent amount, initial Pb(II) concentration, temperature, duration of contact, and presence of competing ions, on the adsorption capacity of MgAl@AC. The MgAl@AC demonstrated a maximum Langmuir adsorption capacity of 94.6 mg/g for Pb(II). Through characterizing the Pb(II)-loaded material, the ion exchange, inner-sphere complexation, and electrostatic attraction were identified as the potential mechanisms of Pb(II) adsorption by MgAl@AC. The Yoon-Nelson and Clark models fit the breakthrough curve well, suggesting that adsorption occurs in surface and pore diffusion-controlled manners. Our findings indicated that MgAl@AC had excellent adsorption capacity, good selectivity, and fast kinetics, highlighting its potential for water treatment applications.

Effectiveness Hydroxyapatite from Chicken Eggshells for Adsorption of Chromium (VI) Metal Ion Electroplating Waste

The largest source of waste comes from household activities. One of the wastes that comes from household activities is chicken eggshells waste. Chicken eggshells contain 94% CaCO3 and can be used as a source of calcium to synthesize hydroxyapatite (Ca10(PO4)6(OH)2) by the precipitation method. Hydroxyapatite can be used as an adsorbent material because it has pores, inert, and wear-resistant so it can adsorb dissolved metal ions Cr (VI) contained in liquid waste from electroplating process. This research aims to synthesize hydroxyapatite from chicken eggshells and determine the optimum pH, contact time, adsorbent mass, and initial concentration of waste which influence the adsorption efficiency using continuous system column adsorption method with fixed flow rate 25 mL/min. In this study, the metal ions Cr (VI) was chosen as adsorbate because Cr (VI) is the main component in electroplating process. This research started from preparation of chicken eggshells waste then synthesized into hydroxyapatite and characterized using XRD, FTIR, and SEM that known structure formed adsorbent is hydroxyapatite and measuring the initial Cr (VI) concentration in waste using AAS with wavelength 357,9 nm. The result of optimizing are the optimum pH 5, contact time of 60 minutes, 3,5 gram of adsorbent mass, and the initial concentration of waste is 10 ppm. The analyzed were done for Cr (VI) concentration. The result showed 99,48% adsorption efficiency with final concentration of Cr (VI) is 0,07 ppm. The adsorption process followed the Freundlich isotherm model with maximum adsorption capacity of 3,93 mg/g hydroxyapatite.

Effective arsenite adsorption from aqueous solution using N- and S-functionalized tetragonal nano-zirconia on chitosan-derived carbon

Arsenic pollution in water is a recurring problem for countries where groundwater is the only source of survival. Adsorption is considered as a promising treatment method to abate arsenic pollution in water due to its numerous admirable advantages. In this paper, a facile functionalization of N- and S-rich nano-zirconia (ZrO2) is presented in-conjunction with in situ precipitation using l-cysteine (Cys), a non-essential amino acid, and prepared with a semi-carbonized (500 °C) chitosan biopolymer, ChiC, (ZrO2-Cys@ChiC) by a hydrothermally assisted method. The interaction of Cys on ZrO2 and ChiC moieties in ZrO2-Cys@ChiC was investigated for the adsorption of toxic arsenite (AsO33-) from water by batch and column adsorption methods. The structure of the prepared materials before and after adsorption of arsenite was characterized by a series of techniques such as powder XRD, XPS, BET, SEM, EDAX, mapping, CHN analysis. The adsorption of arsenite on the prepared ZrO2-Cys@ChiC hybrid adsorbent was best described by the Langmuir adsorption isotherm and the pseudo-second-order kinetic models. Apart from the isostructural and isoelectronic nature of the phosphate ions in the selectivity assay, arsenite adsorption is not hindered at basic pH conditions. After adsorption, the stability of the material was maintained without any change in the surfaces and crystalline nature, as shown by XPS, SEM, and powdered XRD. The reusability and column test results confirmed the potential use of the ZrO2-Cys@ChiC adsorbent for the effective removal of arsenite from water. Combining the high removal density and selectivity with fast kinetics, the prepared ZrO2-Cys@ChiC hybrid adsorbent has great potential for the removal of arsenite from aqueous solutions.

Mesoporous MOF composite for efficient removal of uranium, methyl orange, methylene blue, and Congo red dyes from aqueous solutions

AbstractThe metal‐organic framework (MOF) composites have significant applications in removing water pollutants and heavy metals from aqueous solutions. The MOF‐2@Al2O3 composite was synthesized using zinc nitrate, 1,4‐benzene dicarboxylic acid, and Al2O3 using an in‐situ one‐pot solvothermal method. Physicochemical properties of MOF‐2@Al2O3 are characterized by X‐ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy‐energy dispersive X‐ray spectroscopy (SEM‐EDX), and Brunauer–Emmett–Teller (BET). Batch mode adsorption studies were carried for uranium (VI) effectively from 5‐M HNO3 solution with maximum adsorption of 300.3 mg/g. Furthermore, methyl orange (MO), methylene blue (MB), and Congo red (CR) dyes were removed from the aqueous solution using the fixed‐bed column adsorption method at room temperature. The pseudo second‐order model was well fitted to uranium adsorption rate on MOF‐2@Al2O3 composite, which indicates that chemisorption is the primary mechanism for removing U (VI). Effects of parameters such as flow rate, bed height, initial concentration, time, and pH are studied for azo dyes and U (VI) adsorption. Experimental results indicate that MOF‐2@Al2O3 can efficiently remove uranium and azo dyes with good reusability up to five cycles.

Glutaraldehyde-cross-linked chitosan–alginate composite for organic dyes removal from aqueous solutions

We present an approach for synthesis of a micro-porous composite of two well-known biopolymers, namely chitosan and alginate, using glutaraldehyde as the cross-linking agent. Alginate and chitosan were pre-treated before being mixed, and the two biopolymers' proportions were also monitored. Chitosan was modified using aniline with the help of formaldehyde crosslinker and then the twizer was further crosslinked with alginate using glutaraldehyde. The synthesized composite, glutaraldehyde cross-linked chitosan–alginate composite [(Cs-F-An)-G-Al] was characterized using spectral techniques and employed as a potential adsorbent for three dyes namely Brilliant green, Methyl orange and Patent Blue V. The pHPZC of the material was 7.5 and the maximum monolayer adsorption capacity (Qmax) was found to be 235.82, 198.09 and 117.34 mg g−1 for BG (at pH 8.0), MO (at pH 6.0) and PBV (at pH 3.0) respectively. It was found that the adsorption process follows a Freundlich adsorption isotherm and pseudo second order kinetics. A thermodynamic study revealed that the process of adsorption was enthalpy-driven and spontaneous in nature. Interestingly, the values of the adsorption capacity obtained in column adsorption method are in close agreement with those obtained in batch adsorption experiments, which shows the potential of the synthesized composite for uptake of dyes.

Separation of Manganese Metal Ions with Natural Zeolite Adsorbents and Activated Charcoal of Shall Water use Column Adsorption Method

The purpose of this study is to determine the effectiveness of natural zeolite and activated charcoal to reduce levels of manganese in shall water, determine the effect of contact time with the effectiveness of separation of manganese metal in a shallow well water and know the condition before-after the adsorption process. Method that used was column adsorption with a flow system in which sample is applied to the filtration tube containing zeolite and active carbon. The tests carried out included testing of drinking water parameters namely pH and TDS, testing of manganese content in a shallow well water using Atomic Absorption Spectrophotometer (AAS). The results showed the effectiveness value of natural zeolite adsorbent and activated charcoal using an adsorption column to reduce manganese content in a shallow well water of 90.404%. The longer the use of natural zeolite and activated charcoal, the effectiveness of reducing the manganese content in a shallow well water tends to decrease. A shallow well water samples before the adsorption process have safe conditions for pH and TDS parameters, for manganese metal parameters are also still below the appropriate threshold (SNI) number 01-0220-1987 and RI Permenkes No.492 / MENKES / PER / IV / 2010, after the process of adsorption of f a shallow well water is safe for consumption.

Adsorption of endosulfan from aqueous solution using graphene clay matrix (GCM)

This study involves the adsorption of endosulfan, an organo-chlorine pesticide from aqueous solution using synthesized graphene clay matrix (GCM). Graphene was synthesized from Sucrose C12H22O11 at high temperature and pressure and embedded on the surface of clay to avoid liquid solid separation and was activated by 30% Conc. sulphuric acid. GCM was characterized by various instrumentations like Raman spectroscopy, Fourier transform infra – red spectroscopy (FTIR), thermo gravimetric analyzer (TGA), differential thermo analyzer (DTA). The peak range obtained in raman spectroscopy was 1000–1500 Cm−1 at G band and 2500 – 3500 at the 2D band. FTIR was analyzed for infrared spectral bonds of adsorbent and the C=N, C=C, C=O spectrum indicated Graphene. TGA showed the change of structural composition with respect to increase in temperature and DTA gave the heat evolution graph of graphene monomer respectively. The aqueous solution of endosulfan after adsorption was analyzed by batch and column adsorption methods by varying its concentration, contact time, quantity of adsorbent used, etc. and the favorable results were obtained for the removal efficiency of endosulfan from aqueous solution. The analyte solution was characterized by high performance liquid chromatography (HPLC) and the maximum removal efficiency obtained was 98% in batch studies and 94% in column adsorption method. This method of endosulfan removal will be one of the best methods for the degradation of organo-chlorine derivatives by harmless natural method in a cost-effective manner.

Adsorption of COD in wastewater by Activated Carbon from Rice Husk

Organic pollution occurs due to the presence of organic compound that will causing oxygen depletion and gives potential adverse impacts on human health and the environment. Wastewater from the fish cracker industry typically has high chemical oxygen demand (COD) and it is needed to be treated before release to water bodies in order to reduce the organic pollution. The treatment of COD was done using rice husk activated carbon (RHAC) that produced from agricultural wastes that contributed to waste minimization and reduce the environmental pollution. Therefore, this study emphasized on the feasibility of rice husk activated carbon for removing the COD from fish cracker wastewater. It was also to identify the optimization factors (pH, flow rate and initial concentration of COD) that affecting adsorption by rice husk activated carbon. RHAC was produced by chemical activation using phosphoric acid, H3PO4 and a real wastewater from fish cracker industry was collected, characterized, and treated by using continuous fixed bed column adsorption method. The result shows that the adsorption of COD by RHAC was optimum at pH 2, flow rate 5 ml/min and 5 % v/v initial COD concentration with the COD removal at 31.8% (150 mg/L) which comply with Standard B. Thus, RHAC could be used to develop an alternative method and suitable carbonaceous substances that was used to treat water and wastewater.

Hierarchical approach towards adsorptive removal of Alizarin Red S dye using native chitosan and its successively modified versions.

In the present work, native chitosan (Ch) along with its chemically and physico-chemically modified versions, namely sulphate cross-linked chitosan (SCC) and sulphate cross-linked chitosan-bentonite composite (SCC-B), were employed as potential adsorbents for the removal of an anionic dye, Alizarin Red S (ARS) from aqueous solutions. All three adsorbents were extensively characterized using techniques such as Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray, X-ray diffraction, Brunauer-Emmett-Teller analysis, thermogravimetric-differential thermal analysis, and pH point of zero charge. Various parameters were optimized, including pH of dye solution, contact time, adsorbent dose, initial adsorbate concentration and temperature of adsorption. Four adsorption isotherm models were studied and it was found that the Freundlich model was best-fit for all three systems. Maximum adsorption capacities towards adsorption of ARS were found to be 42.48, 109.12 and 131.58 mg g-1 for Ch, SCC and SCC-B, respectively. Kinetics of adsorption was examined by employing three well-known models in order to deduce the mechanism of adsorption. Thermodynamic studies show that the process is spontaneous and exothermic for all adsorbents employed. Furthermore, it was observed that for large sample volumes, the column adsorption method was more effective compared to the batch method.

Removal of Oil and Grease in Wastewater using Palm Kernel Shell Activated Carbon

Oil and grease wastewater is produced from many sources such as industry and municipal. The discharge of oil and grease in wastewater system causes bad effect towards the environment and wastewater system itself. Palm Kernel Shells (PKS), an agricultural waste was chosen to see its ability in removing oil and grease in wastewater. The PKS was carbonized at 400 °C, activated with KOH and carbonized again at 800 °C. The parameter affecting oil and grease removal such as different oil and grease concentration, contact time and flow rate were studied. The oil and grease removal study was conducted by the column adsorption method and followed by the gravimetric method to identify the remaining oil and grease. PKS activated carbon shows maximum removal of 99.89% at flow rate 1mL/min after 6 hours contact time with 5%w/v initial concentration of wastewater. SEM micrograph of PKS activated carbon after adsorption of oil and grease shows that oil and grease has covered the pores of the surface of the PKS activated carbon. Overall, the PKS activated carbon has the ability in removing oil and grease which indicates that PKS can be used as a alternative treatment in removing oil and grease.

Lithium recovery from spent Li-ion batteries using coconut shell activated carbon

Lithium is one of scarce natural resources in the world that need to be preserve. One of the way in preserving the resource is by recovery the rich source of the lithium such as in the spent batteries. It is necessary to develop a recovery method which is efficient and low-cost to be able to recover the lithium in an economic scale. In this study, low-cost activated carbon (AC) from coconut shell charcoal was prepared by chemical and physical activation methods and tested for Li removal from Co, Mn, and Ni ions in semi-continuous columns adsorption experiments. The maximum surface area is 365 m2/g with the total pore volume is 0.148 cm3/g that can be produced by physical activation at 800 °C. In the same activation temperature, activation using KOH has larger ratio of micropore volume than physical activation. Then, the adsorption capacity and selectivity of metal ions were investigated. A very low adsorption capacity of AC for Li ions in batch adsorption mode provides an advantage in column applications for separating Li from other metal ions. The AC sample with chemical activation provided better separation than the samples with physical activation in the column adsorption method. During a certain period of early adsorption (lag time), solution collected from the column outlet was found to be rich in Li due to the fast travel time of this light element, while the other heavier metal ions were mostly retained in the AC bed. The maximum lag time is 97.3 min with AC by KOH activation at 750 °C.

Adsorption and kinetics study of manganesse (II) in waste water using vertical column method by sugar cane bagasse

Removal of heavy metal content in wastewater has been largely done by various methods. One effective and efficient method is the adsorption method. This study aims to reduce manganese (II) content in wastewater based on column adsorption method using absorbent material from bagasse. The fixed variable consisted of 50 g adsorbent, 10 liter adsorbate volume, flow rate of 7 liters / min. Independent variable of particle size with variation 10 – 30 mesh and contact time with variation 0 - 240 min and respon variable concentration of adsorbate (ppm), pH and conductivity. The results showed that the adsorption process of manganese metal is influenced by particle size and contact time. The adsorption kinetics takes place according to pseudo-second order kinetics with an equilibrium adsorption capacity (qe: mg / g) for 10 mesh adsorbent particles: 0.8947; 20 mesh adsorbent particles: 0.4332 and 30 mesh adsorbent particles: 1.0161, respectively. Highest removal efficience for 10 mesh adsorbent particles: 49.22% on contact time 60 min; 20 mesh adsorbent particles: 35,25% on contact time 180 min and particle 30 mesh adsorbent particles: 51,95% on contact time 150 min.

Removal of furan and phenolic compounds from simulated biomass hydrolysates by batch adsorption and continuous fixed-bed column adsorption methods

It has been proposed to remove all potential inhibitors and sulfuric acid in biomass hydrolysates generated from dilute-acid pretreatment of biomass, based on three steps of sugar purification process. This study focused on its first step in which furan and phenolic compounds were selectively removed from the simulated hydrolysates using activated charcoal. Batch adsorption experiments demonstrated that the affinity of activated charcoal for each component was highest in the order of vanillic acid, 4-hydroxybenzoic acid, furfural, acetic acid, sulfuric acid, and xylose. The affinity of activated charcoal for furan and phenolic compounds proved to be significantly higher than that of the other three components. Four separation strategies were conducted with a combination of batch adsorption and continuous fixed-bed column adsorption methods. It was observed that xylose loss was negligible with near complete removal of furan and phenolic compounds, when at least one fixed-bed column adsorption was implemented in the strategy.

Adsorption recovery of Pd(II) from aqueous solutions by persimmon residual based bio-sorbent

A low cost bio-sorbent, named “PPF resin”, was prepared by immobilizing persimmon residual with formaldehyde and it was characterized before and after adsorption of Pd(II). The adsorption behavior of PPF resin towards Pd(II) from aqueous solutions was studied by batch and column adsorption methods. The adsorption equilibrium of Pd(II) on PPF resin was achieved within 840min, and the experimental data were well fitted with the pseudo-second-order rate model. Higher initial concentration and adsorption temperature led to higher equilibrium adsorption amount, and the adsorption isotherms could be well described by Langmuir model. The column studies suggested that the resin was effective for the adsorption of Pd(II) from aqueous solutions, and the loaded Pd(II) could be easily desorbed by acidic thiourea solution. The adsorption process of Pd(II) on PPF resin might be the multiple reactions of electrostatic interaction and reductive adsorption, in which Pd(II) was reduced to Pd(0) as confirmed by the XRD pattern of PPF resin after adsorption of Pd(II). The resin exhibited outstanding selective adsorption towards Pd(II) from actual leach liquor of waste PCBs at a high concentration of HNO3. The results suggested that the PPF resin can be used as an active bio-sorbent for the recovery of Pd(II) from aqueous environment.

Modelling of Adams-Bohart and Yoon-Nelson on the Removal of Oil from Water Using Microwave Incinerated Rice Husk Ash (MIRHA)

- This study investigated the possible use of Microwave Incinerated Rice Husk Ash (MIRHA) as adsorbent for the treatment of wastewater generated from oil and gas industry using the column adsorption method. Adams-Bohart and Yoon-Nelson models were used to analyze experimental data. MIRHA was found to be porous, have high surface area and consist of 87-97% silica. Results show that both Adams-Bohart and Yoon-Nelson models can be used to describe experimental data.

A highly efficient p-tert-butylcalix[8]arene-based modified silica for the removal of Hexachlorocyclohexane isomers from aqueous media

Hexachlorocyclohexane (HCH) is an organochlorine insecticide that exists in various isomeric forms, where α-, β-, and γ-isomers are persistent and impart toxicity to water bodies. The current article explains about the removal of HCH using p-tert-butylcalix[8]arene-based modified silica. The modified silica is characterized through Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) and also by batch and column adsorption method for maximum removal efficiency. Variations in concentrations of HCH were monitored by GC-μECD. Various parameters that affect uptake like pH; agitation time, adsorbent dosage, and concentration of HCH were optimized as, pH 8, 60 min, 20 mg, and 1 mg L−1, respectively. The adsorption data were found to be best fitted with Freundlich adsorption model and followed pseudo-second-order kinetic equation. From the Thomas model, kinetic coefficient (kTH cm3 mg−1 min−1) values were found to be 0.054, 0.054, 0.049, 0.055 and maximum solid phase concentration (qo mg g−1) of hexachlorocyclohexane (HCH) isomers (α, β, γ, δ) on the modified silica which was calculated as 112.5, 110.8, 108.5, 114.2, respectively. The modified silica can be reused efficiently and under optimized conditions can effectively remove HCH isomers from real wastewater samples.

Removal of Endotoxin from Collagen Solution by Lectin-grafted Silica Beads

In the present study,we propose to study endotoxin absorption/removal processes in collagen solutions by taking advantage of the unique adsorption characteristics of lectin molecules specifically onto the poly-saccharide components in endotoxin.The surface of silica beads was pretreated with acid-etching process leaving reactive OH groups which facilitated the adoption of amino-siloxane group for grafting of lectin molecules.The preliminary results demonstrated that high levels of adsorption of endotoxin were all readily achievable(99%) under grafting formulation with various concentrations of lectin,such as 1,2 and 5 g/L.The results also indicated that 30 pieces of lectin-grafted silica beads would efficiently adsorb endotoxin from a volume of 9.6 mL collagen solution.For future work,we plan to evaluate designs of column adsorption method and system for the removal of endotoxin in collagen material.