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Effect of (A) influent solution pH, (B) influent volumetric flux, (C) influent AR27 concentration, and (D) LEC bed height on the dye biosorption breakthrough curve.
Source publication
In this work, the biosorption behavior of acid red 27 (AR27) dye using Eichhornia crassipes leaves (LECs) in a packed-bed column was investigated by varying relevant operational parameters and assessment of mathematical models. Results showed that the zero-charge point of LECs was 2.37 and that optima pH and volumetric flux of the influent solution...
Contexts in source publication
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... influence of solution pH on the biosorption of an adsorbate has been extensively studied in batch systems; however, very few studies have examined the effect of pH on the biosorption of the adsorbate of interest in continuous systems 32,44 . Figure 3A displays the experimental breakthrough curves for AR27 biosorption with influent AR27 solutions with pHs in the range of 1.5-6.0. It was found that the pH of the inlet solution significantly affected the gradient Table 1. ...
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... shown in Fig. 3A, the service and saturation time values of the packed-bed column were longer at pH 2.0, followed by those observed at pHs 1.5, 3.0, 4.0, 5.0, and ...
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... of the influent volumetric flux on AR27 biosorption. Figure 3B shows experimental AR27 breakthrough curves, derived using influent dye solutions with different volumetric fluxes, namely 37.67, 56.5, 75.34, and 113 L/m 2 h (corresponding to flow rates of 5, 7.5, 10, and 15 mL/h), while the LEC packed-bed height (2 cm), inlet solution pH (2.0), and influent AR27 concentration (50 mg/L) values remained constant. AR27 dye was not detected in the outflow effluents during the first 70, 45, 22, and 11 h of packed-bed column operation, when the influent volumetric fluxes were 37.67, 56.5, 75.34, and 113 L/m 2 h , respectively, indicating that the column service time decreased as the volumetric flux of the influent solution increased. ...
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... results show that at a volumetric flux of 56.5 L/m 2 h , the highest mass of AR27 was removed, and the specific AR27 biosorption capacity and volumetric AR27 biosorption capacity values were maximal; therefore, subsequent studies were carried out using an influent solution with a volumetric flux of 56.5 L/m 2 h. Figure 3C shows the AR27 biosorption breakthrough curves obtained with different inlet AR27 concentrations, ranging from 30 to 400 mg/L (30,50,75,100,200, and 400 mg/L), when the inlet pH, volumetric flux of the influent solution, and LEC bed height remained constant at 2.0, 56.5 L/m 2 h , and 2 cm, respectively. ...
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... were carried out using influent solution pH, volumetric flux, and AR27 concentration of 2.0, 56.5 L/m 2 h , and 200 mg/L, respectively. Figure 3D displays the breakthrough profiles of AR27 biosorption at various bed heights. It is apparent that the slope and shape of the breakthrough curves differ with a variation in the LEC bed height. ...
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... it was observed that these four models and the modified dose-response model exhibited values of R 2 , RMSE, and AIC that were very close to each other. Furthermore, the BDST, Thomas, Yoon-Nelson, and dose-response models were able to adequately predict the experimental values of q, N v , τ and τ , respectively (Tables 2, 3, 4, 5). It was confirmed that upon using the values of the constants a and b in the logistic model along with the values of other operational and system variables, the kinetic parameters of the BDST, Thomas, and Yoon-Nelson models could be calculated from the mathematical relationships provided in Table 1 42 . ...
Citations
... The samples were pretreated with nitrogen at 373 K. The surface area was calculated by the multipoint BET method (Brunauer, Emett and Teller) and the distribution of the size of the pore and its volume by the BJH method (Barret, Joyner and Halenda) [52,53]. ...
There is a growing need for an economical and efficient method capable of removing heavy metals from residual water. The current contribution aimed to evaluate the capacity of onion peel, an abundant agroindustrial waste product, to remove divalent cobalt (Co2+) from aqueous solutions. Onion peel was submitted to proximal chemical analysis, and various operational factors involved in biosorption were tested. The most suitable temperature (30 °C), pH (7.0), and biosorbent particle size (300–800 µm) were found. With an initial Co2+ concentration of 380 mg L−1, the maximum capacity of Co2+ removal was 59.88 mg g−1 in 120 min. The pseudo-second order and Langmuir models provided the best fit to the experimental kinetics and equilibrium of Co2+ biosorption, respectively. The thermodynamic study evidenced an exothermic, non-spontaneous, and favorable reaction (ΔH0 = −5.78 kJ mol−1; ΔS0 = −21.13 J mol−1 K−1), suggesting the formation of stable bonds in the biosorbent-Co2+ complex. The carbonyl and hydroxyl groups apparently play a fundamental role in Co2+ removal, and electrostatic attraction, ion exchange, and chemisorption are the principal mechanisms. Thus, the biosorption of Co2+ by onion peel has potential as an economical, eco-friendly, efficient, and sustainable treatment for wastewater.
... From this curve, the breakthrough time (tb) was determined to be Ct/Ci = 0.1, i.e., when Ct reaches 10% of Ci. The exhaustion time (te) is the time at which Ct reaches 90% of Ci, and it is defined as Ct/Ci = 0.90 [16,29]. The effluent volume (Veff, mL) was calculated using Equation (1): ...
... From this curve, the breakthrough time (t b ) was determined to be C t /C i = 0.1, i.e., when C t reaches 10% of C i . The exhaustion time (t e ) is the time at which C t reaches 90% of C i , and it is defined as C t /C i = 0.90 [16,29]. The effluent volume (V eff , mL) was calculated using Equation (1): ...
... The empty bed contact time, which is the length of time an influent under treatment maintains contact with the monolithic column, is estimated using Equation (2): where V c is the volume of the empty column (mL). The total MB adsorption capacity of the cryogel column (q total , mg) at the appropriate C i and Q was estimated using Equation (3) [16,29,30]: ...
A continuous-flow system based on a green and cost-effective monolithic starch cryogel column was successfully developed for removing methylene blue (MB). The proposed column exhibited high removal efficiency (up to 99.9%) and adsorption capacity (25.4 mg·g−1) for synthetic and real samples with an adsorbent cost of USD 0.02. The influence of various operation parameters, including the flow rate, initial concentration, column height, and temperature, on the MB removal efficiency was examined and reported. The MB removal efficiency remained >99% in the presence of potential interferences, highlighting the good performance of the cryogel column. The Yoon–Nelson dynamic model explained the MB adsorption better than the Bohart–Adams model, as indicated by the higher R2 values (R2 = 0.9890–0.9999) exhibited by the former and current trends of its parameters. The MB removal efficiency of the cryogel column remained at 62.7% after three reuse cycles. The wastewater containing MB collected from a local batik-production community enterprise in Phuket, Thailand was applied to the proposed continuous-flow system under optimum conditions, and results indicated that 99.7% of the MB present in 2.4 L of wastewater was removed. These results validate the excellent application potential of the cryogel column for the continuous-flow adsorption of MB. This study will facilitate future industrial applications and process designs of the continuous-flow system.
... So, industrial effluents containing AR27 adversely affect humans and animals with effects that include respiratory problems, birth defects, allergies, tumors, genotoxicity, cytotoxicity, embryotoxicity, mutagenicity, carcinogenicity and endocrine disruption. Furthermore, wastewater discharges, containing AR27, into natural water bodies affect the viability and photosynthetic process of aquatic plants by reducing sunlight penetration and also deprives aquatic animals of the oxygen required for their vital functions [12][13][14]. ...
... According to the sensitivity analysis for the minimum time of full depletion of aromatic metabolites (R 3 ), the model that showed the highest correlation coefficient was the quadratic model (r 2 = 0.9909), which is shown in equation (12). For this case, the strongest factor with the major influence upon this response is the quadratic coefficient of the initial AR27 concentration (β 2 ) that indicates the dependence of the degradation time of aromatic metabolites on initial dye concentration, which describes that the higher the dye concentration, the longer the degradation time. ...
In this work, it is presented a first approach of a mathematical and kinetic analysis for improving the decoloration and further degradation process of an azo dye named acid red 27 (AR27), by means of a novel microbial consortium formed by the fungus Trametes versicolor and the bacterium Pseudomonas putida. A multivariate analysis was carried out by simulating scenarios with different operating conditions and developing a specific mathematical model based on kinetic equations describing all stages of the biological process, from microbial growth and substrate consuming to decoloration and degradation of intermediate compounds. Additionally, a sensitivity analysis was performed by using a factorial design and the Response Surface Method (RSM), for determining individual and interactive effects of variables like, initial glucose concentration, initial dye concentration and the moment in time for bacterial inoculation, on response variables assessed in terms of the minimum time for: full decoloration of AR27 (R1 = 2.375 days); maximum production of aromatic metabolites (R2 = 1.575 days); and full depletion of aromatic metabolites (R3 = 12.9 days). Using RSM the following conditions improved the biological process, being: an initial glucose concentration of 20 g l⁻¹, an initial AR27 concentration of 0.2 g l⁻¹ and an inoculation moment in time of P. putida at day 1. The mathematical model is a feasible tool for describing AR27 decoloration and its further degradation by the microbial consortium of T. versicolor and P. putida, this model will also work as a mathematical basis for designing novel bio-reaction systems than can operate with the same principle of the described consortium.
... It is observed that desorption cycle took 55 min for complete exhaustion.From the desorption experiment, it can be concluded that very small amount of HCl is needed for total desorption of the column with a bed depth of 6 cm on MABL. The mineral acids are proton-exchange agents, which could wash away high valance metal ions from bio-adsorbent (Rajeswari et al 2022,Ramirez et al 2021. The desorbed column is then washed with distilled water and tried for further use. ...
... Breakthrough time (tb) is defined as the period when the phos phate concentration in the effluent (Ct) approaches 10% of the influent concentration (C0) i.e., Ct/C0 = 0.10. In addition, the exhaustion time (te) is the moment when Ct reaches 90% of C0 (Ct/C0 = 0.90) [44,45]. The effluent volume (Veff; mL) can be determined using Equa tion (1) as follows: ...
... Breakthrough time (t b ) is defined as the period when the phosphate concentration in the effluent (C t ) approaches 10% of the influent concentration (C 0 ), i.e., C t /C 0 = 0.10. In addition, the exhaustion time (t e ) is the moment when C t reaches 90% of C 0 (C t /C 0 = 0.90) [44,45]. The effluent volume (V eff ; mL) can be determined using Equation (1) as follows: ...
Toward the development of a practical and green approach for removing phosphate from water, a monolithic cryogel based on starch and calcium silicate hydrate (Cry–CSH) was employed as a phosphate adsorbent in a continuous flow system for the first time. The influence of flow rate, initial phosphate concentration, and adsorbent height on the adsorption efficiency was investigated. As the rate of flow and the initial concentration of phosphate increased, the total quantity of adsorbed phosphate dropped; however, the performance of the column was greatly enhanced by an increase in adsorbent height. The experimental data fit the Adams–Bohart model better than the Thomas and Yoon–Nelson models at the beginning of the adsorption process. To evaluate its applicability, the continuous flow system based on the monolithic Cry–CSH column was applied for the removal of phosphate from the discharge effluent of the Patong Municipality Wastewater Treatment Plant (Phuket, Thailand), achieving an excellent total adsorption of 94.61%.
... So, industrial effluents containing AR27 adversely affect humans and animals with effects that include respiratory problems, birth defects, allergies, tumors, genotoxicity, cytotoxicity, embryotoxicity, mutagenicity, carcinogenicity and endocrine disruption. Furthermore, wastewater discharges, containing AR27, into natural water bodies affect the viability and photosynthetic process of aquatic plants by reducing sunlight penetration and also deprives aquatic animals of the oxygen required for their vital functions [12][13][14]. ...
... According to the sensitivity analysis for the minimum time of full depletion of aromatic metabolites (R 3 ), the model that showed the highest correlation coefficient was the quadratic model (r 2 = 0.9909), which is shown in equation (12). For this case, the strongest factor with the major influence upon this response is the quadratic coefficient of the initial AR27 concentration (β 2 ) that indicates the dependence of the degradation time of aromatic metabolites on initial dye concentration, which describes that the higher the dye concentration, the longer the degradation time. ...
... Previous studies showed that the leaves of water hyacinth (Pontederia crassipes) (LEC) effectively biosorb AR27 dye from aqueous solutions in both batch and continuous systems [23][24][25]. In addition, this dye can be recovered with 100% desorption efficiency from the loaded LEC biomass by using 0.025 M NaHCO 3 as the eluent/desorbent. ...
... A 75 mg/L AR27 test solution was prepared by diluting the AR27 stock solution with deionized water. Its pH was adjusted with 0.1 M HCl to 2.0 which is the optimum for AR27 biosorption by LEC in a continuous system with a packed-bed column reactor [25]. The AR27 concentration was determined at 520 nm in a Thermo Scientific UV-Vis Evolution 201 spectrophotometer (Thermo Fisher Scientific, Waltham, MA, USA) [23]. ...
... The 200-mesh stainless steel sieves prevented biosorbent loss. The LEC packed-bed porosity (ε b ) and density (ρ b ) were ~25% and 0.188 g/cm 3 , respectively [25]. NaHCO 3 eluent (0.025 M, pH 8.0, and volumetric flux of 37.67, 56.5, 75.34 or 113 L/m 2 ·h) or influent AR27 solution (75 mg/L, pH 2.0, and volumetric flux = 56.5 L/m 2 ·h) were introduced at the base of the column through a sintered glass diffuser, which enhanced fluid dispersion and distribution within the column. ...
We investigated the capacity of water hyacinth leaves (LEC) to biosorb 75 mg/L acid red 27 (AR27) in a continuous system comprising 30 successive biosorption/desorption cycles in a packed-bed column at pH 2.0 and 56.5 L/m ² ·h volumetric flux. Using 0.025 M NaHCO 3 eluent at 113 L/m ² ·h volumetric flux, all the dye was desorbed (100% desorption efficiency) from the loaded LEC biomass within 5–6 h. The same biosorbent was used for 147.5 consecutive days. The AR27 biosorption capacity, breakthrough time, and exhaustion time decreased from 69.4 to 34.5 mg/g, 74.81 to 14.1 h, and 101.1 to 34.1 h, respectively, and the critical bed height increased from 1.04 to 2.35 cm, as the number of biosorption/desorption cycles increased from 1 to 30. LEC life factor based on biosorption capacity predicted that the packed bed would be exhausted after 51.95 cycles. LEC is a promising biosorbent for bioremediation of AR27-laden wastewaters.
... For industrial and other large scale applications it is convenient to carry out the process in a fixed bed column reactor where biomaterial is loaded into the reactor to operate as the fixed bed (Ramirez-Rodriguez et al., 2021). The exact mechanism that occurs is adsorption of metal ions on bioadsorbent are ion exchange, Van der Waal's forces, chelation, electrostatic interaction, complexation etc. (Vijayraghaban and Yun, 2008). ...
The presented study is an experimentation of bioadsorption of cadmium on lentil husk (LH) stacked in fixed bed column reactor. Here the concept of circular economy is integrated to demonstrate its compliance with biological adsorption. In addition sustainability evaluation of the work has been done with respect to environmental, economical and executional procedure. Regarding experimental parameters adsorption capacity, percentage adsorption and breakthrough time all found to be dependent on the variation of design parameters. Sorbate (cadmium) concentration in treated effluents was inversely proportional to bed height and directly related to flow rate owing to prolonged interaction with metal binding sites. Adsorption capacity (164.25 mg g⁻¹) peaked up at highest feed concentration due to formation of concentration gradient overcoming the resistance offered during transfer of solute. Desorption was fruitful (up to ~96%) and the fixed bed regained its performing capacity successively. Industrial effluents were reclaimed with high accuracy for considerable duration.
... For industrial and other large scale applications it is convenient to carry out the process in a fixed bed column reactor where biomaterial is loaded into the reactor to operate as the fixed bed (Ramirez-Rodriguez et al., 2021). The exact mechanism that occurs is adsorption of metal ions on bioadsorbent are ion exchange, Van der Waal's forces, chelation, electrostatic interaction, complexation etc. (Vijayraghaban and Yun, 2008). ...
... However, these methods tend to suffer from a number of disadvantages, including high costs, complexity, and/or the generation of hazardous wastes [14]. In contrast, the biosorption approach appears to be a more attractive and viable treatment technology for removing heavy metals from industrial wastewaters because of its ease of operation, simplicity of design, adaptability, flexibility, effectiveness, efficacy, efficiency, biosorbent regeneration, eco-friendliness, and insensitivity to toxic pollutants [15,16]. Thus, a vast array of biomaterials have been studied in terms of their abilities to remove heavy metals from single metal aqueous solutions, with examples including nonliving filamentous fungi, bacteria, yeasts, microalgae, and seaweed, in addition to agro-industrial, fishery, and forestry biowastes [17]. ...
... The CS particles were degassed with nitrogen at 373 K. Then, we determined the specific surface area of the CS using the Brunauer, Emmett, and Teller (BET) multipoint method, and the total pore volume and pore diameter by applying the Barrett, Joyner, and Halenda (BJH) method [16]. ...
This work explored the technical feasibility of using crab shell (CS) as a promising, low-cost biosorbent to individually and simultaneously remove Zn2+ and Ni2+ from aqueous solutions. It was found that in both monometallic and bimetallic systems, Zn2+ and Ni2+ biosorption by CS was strongly dependent on the solution pH, with the optimum biosorption occurring at a pH of 6.0 for both heavy metals. The obtained isotherms for Zn2+ and Ni2+ biosorption onto CS in monometallic and bimetallic systems demonstrated that CS has a higher affinity for Zn2+ than for Ni2+. The experimental equilibrium data for the bimetallic system revealed that when one heavy metal is present in the system, there is a decrease in the equilibrium biosorption capacity for the other heavy metal; therefore, the combined action of Zn2+ and Ni2+ was antagonistic. The Sips and Redlich–Peterson isotherm models best fitted the equilibrium biosorption data for Zn2+ and Ni2+ in the monometallic systems, while the modified Sips model best fitted the binary biosorption equilibrium data. DRIFTS analyses indicated that carbonate ion, chitin, and proteins are mainly involved in the biosorption of Zn2+ and Ni2+ by CS from aqueous solutions, as confirmed using a range of analytical techniques.
