Source identification and evaluation of surface water quality using factor and discriminant analysis

This study utilizes factor and discriminant analysis to identify the parameter source and evaluate the quality of water from ex-mining ponds and lakes in Selangor. Factor analysis (FA) which explain 83.77% of the surface water quality variation shows that As and Cd that mostly originated from mining activity, and pH are the parameters responsible for the major variation in the surface water quality and were strongly associated with varimax factor 1 (VF1), while Pb, Mn and DO were associated with varimax factor 2 (VF2). The Discriminant analysis (DA) reveals that As, Cd, Mn, Fe and pH are the parameters that significantly differentiate ex-mining ponds from the lake (p < 0.05 and F - ratio >> 1), and supported by the correlation study. The elevated metal concentrations in ex-mining ponds compared to lakes were plausibly associated with the past mining operation, thereby indicating heavy metal dominance in ex-mining ponds. DO and BOD are associated with the anthropogenic input from residential sources. Findings of this study therefore show the need and usefulness of multivariate statistical analysis to get information on the quality status of surface water.Keywords: Discriminant analysis, Ex-mining pond, Factor analysis, Lake, Water quality

Equilibrium, Thermodynamic, and Kinetic Studies

Publisher Copyright: © 2022 Razia Sulthana et al.The economic viability of adsorbing crystal violet (CV) using pepper seed spent (PSS) as a biosorbent in an aqueous solution has been studied. A parametrical investigation was conducted considering parameters like initial concentration of dye, time of contact, pH value, and temperature variation. The analysis of experimental data obtained was carried out by evaluating with the isotherms of Freundlich, Sips, Tempkin, Jovanovic, Brouers-Sotolongo, Toth, Vieth-Sladek, Radke-Prausnitz, Langmuir, and Redlich-Peterson. The adsorption kinetics were studied by implementing the Dumwald-Wagner, Weber-Morris, pseudo-first-order, pseudo-second-order, film diffusion, and Avrami models. The experimental value of adsorption capacity (Qm=129.4 mg g-1) was observed to be quite close to the Jovanovic isotherm adsorption capacity (Qm=82.24 mg g-1) at (R2), coefficient of correlation of 0.945. The data validation was found to conform to that of pseudo-second-order and Avrami kinetic models. The adsorption process was specified as a spontaneous and endothermic process owing to the thermodynamic parametrical values of ΔG0, ΔH0, and ΔS0. The value of ΔH0 is an indicator of the process's physical nature. The adsorption of CV to the PSS was authenticated from infrared spectroscopy and scanning electron microscopy images. The interactions of the CV-PSS system have been discussed, and the observations noted suggest PSS as a feasible adsorbent to extract CV from an aqueous solution.publishersversionpublishe

Isotherm, kinetic and modeling studies

Funding Information: Funding: The Deanship of Scientific Research at King Khalid University General Research Project under the grant number (R.G.P.2/138/42) and Taif University researchers supporting project number (TURSP–2020/157), Taif University, Taif, Saudi Arabia. Funding Information: Acknowledgments: The co‐author Ali E. Anqi would like to extend his appreciation to the Deanship of Scientific Research at King Khalid University for the support he received through General Re‐ search Project under the grant number (R.G.P.2/138/42). This work was supported by Taif Univer‐ sity researchers supporting project number (TURSP–2020/157), Taif University, Taif, Saudi Arabia. The first author was thankful to the Directorate of Minorities, Govt. of Karnataka for providing PhD fellowship to conduct the research. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.The first-ever use of halloysite nanotube (HNT), a relatively low-cost nanomaterial abun-dantly available with minor toxicity for removing brilliant green dye from aqueous media, is re-ported. The factors affecting adsorption were studied by assessing the adsorption capacity, kinetics, and equilibrium thermodynamic properties. All the experiments were designed at a pH level of around 7. The Redlich-Peterson isotherm model fits best amongst the nine isotherm models studied. The kinetic studies data confirmed a pseudo model of the second order. Robotic investigations pro-pose a rate-controlling advance being overwhelmed by intraparticle dispersion. The adsorbent fea-tures were interpreted using infrared spectroscopy and electron microscopy. Process optimization was carried out using Response Surface Methodology (RSM) through a dual section Fractional Fac-torial Experimental Design to contemplate the impact of boundaries on the course of adsorption. The examination of fluctuation (ANOVA) was utilized to consider the joined impact of the boundaries. The possibilities of the use of dye adsorbing HNT (“sludge”) for the fabrication of the composites using plastic waste are suggested.publishersversionpublishe

A recent study on remediation of direct blue 15 dye using halloysite nanotubes

R.G.P.2/138/42 TURSP–2020/157A set of lab‐scale experiments were designed and conducted to remedy Direct Blue 15 (DB15) dye using nontoxic halloysite nanotubes (HNT) with the view to be utilized in a textile industrial effluent (TIE). The DB15 adsorbed‐HNT “sludge” was used as a reinforcing agent and plas-tic waste to fabricate the composite. To advance the knowledge and further understand the chemical phenomena associated with DB15 adsorption on HNT, different factors like pH value, adsorbate initial concentration, adsorbent dosage, and temperature on the composite were affected experi-mentally tested. To estimate the adsorption capacity of HNT, nine isotherm models were applied, and it was identified that the Brouers–Sotolongo adsorption isotherm model represented the best accuracy for predicting the adsorption behavior of the HNT. Likewise, the pseudo‐second‐order reaction was the predominant mechanism for the overall rate of the multi‐step dye adsorption pro-cess. Additionally, it was demonstrated that the mass transfer during the process is diffusion‐con-trolled, and thermodynamic assessments showed that the process is physisorption.publishersversionpublishe

Sustainable adsorption method for the remediation of malachite green dye using nutraceutical industrial fenugreek seed spent

Nutraceutical industrial fenugreek seed spent (NIFGS), a relatively low-cost material abundantly available with nearly negligible toxicity for the bioremediation of malachite green (MG) dye from aqueous media, is reported. Studies on the various parameters affecting the adsorption capacity of NIFGS were carried out to evaluate the kinetics and the equilibrium thermodynamics. All the experiments were designed at about pH 7. The adsorption isotherm model proposed by Langmuir fits better than the Freundlich isotherm model. Kinetic study data confirms the viability of pseudo-second-order model. Calculated thermodynamic factors suggest that the adsorption phenomenon is endothermic, almost instantaneous, and physical in nature

Study on bioremediation of azo dyes using nutraceutical industrial spent and resultant waste as filler materials to fabricate green composites / Syed Noeman Taqui

The ever-increasing volume of spent/waste from Nutraceutical Industries accumulating into millions of tons is a serious threat to environment. Its disposal by incineration/burning as fuel adds to the carbon foot print. Nutraceutical Industrial Spent (NIS) has no feed or fertilizer value, since it has undergone process using toxic organic solvents. The present study explores the novel concept of using NIS as biosorbent for the remediation of toxic dyes and utilizing the resultant “sludge” as filler/reinforcing material with non-biodegradable plastics to fabricate polypropylene green thermoplastic and unsaturated polyester resin composites. Fennel seed spent, coriander seed spent, and cumin seed spent have been explored for bioremediation of Congo red, Acid Blue 113, Acid Red 119 and metal-complex dye, Acid Black 52 in aqueous solutions and textile industrial effluent. By batch experiments, the operating variables like initial dye concentration, adsorbent dosage, particle size, temperature, contact time and pH were optimized. pH 2 is ideal to remove azo dyes from aqueous solutions using NIS as adsorbent with enhanced adsorption capacity. For comparison, bioremediation of Congo red dye was carried out at almost neutral pH which displayed equally interesting results. The results indicate that broad range of pH 2 to 7 can be used for remediation of bisazo dyes from aqueous solutions. The adsorption methodology was studied using nine models. Of all the adsorption studies thermodynamic analysis showed the adsorption is favorable and endothermic. The low H value indicates that the adsorption is a physical process involving weak chemical interactions like hydrogen bonds and van der Waals interactions. The kinetics revealed that the adsorption process showed pseudo second-order tendencies with the equal influence of intra-particle as well as film diffusion. The process of interaction between the adsorbent and adsorbate is physical and maximum adsorption takes place between pH of 2 and 4 and at 30oC. The SEM images showed that NIS is highly fibrous matrix with a hierarchical porous structure. By FTIR presence of cellulosic and ligno-cellulosic matter in spent was confirmed and they impart hydrophilic and hydrophobic properties. The thermoplastic composites of polypropylene using dye-adsorbed NIS as filler/reinforcing material were evaluated for physico-mechanical and tribological properties and compared with polypropylene/NIS composites. Flexural strength and flexural modulus of composites were improved by adding dye-adsorbed NIS and NIS into polypropylene matrix. The wear volume of polyprolyene/dye-adsorbed NIS composites and polypropylene/NIS composites increased with increase in sliding distance, applied load and filler loading. Increased filler composition showed adverse impact on abrasive wear. The water absorption characteristics of thermoplastic composites exhibited gradual increase in weight due to hydrophilic nature of lignocellulosic filler. The SEM of surface morphology of fractured composite revealed damage to the matrix at higher dye adsorbed-NIS content. Unsaturated polyester composites of dye adsorbed-NIS and NIS showed improved chemical resistance and dimensional stability but reduced in tensile strength by increasing the filler content. The study infers that utilization of dye adsorbed-NIS as useful industrial materials may lead to creation of more jobs, ecologically alleviating waste disposal problems and helping in ameliorating the environmental pollution

Sustainable Adsorption Method for the Remediation of Crystal Violet Dye Using Nutraceutical Industrial Fenugreek Seed Spent

Nutraceutical industrial fenugreek seed spent (NIFGS), a relatively low-cost material abundantly available with little toxicity is used in crystal violet (CV) dye remediation from aqueous media and reported in the present study. To access the adsorption capacity, the factors affecting it are kinetics and the equilibrium thermodynamics. All the experiments were designed at approximately pH 7. The adsorption isotherm model proposed by Langmuir fits better than the Freundlich isotherm model. Kinetic studies data confirm the pseudo-second order model. It is evident from thermodynamic parameter values that the process of adsorption is endothermic, physical and dynamic. The process optimization of independent variables that influence adsorption was carried out using response surface methodology (RSM) through bi-level fractional factorial experimental design (FEED). The analysis of variance (ANOVA) was implemented to investigate the combined effect of parameters influencing adsorption. The possibilities of using dye-adsorbed NIFGS (“sludge”) for the fabrication of the composites using plastic waste are suggested

Bioremediation of Textile Industrial Effluents Using Nutraceutical Industrial Spent: Laboratory-Scale Demonstration of Circular Economy

This research reports the first-ever study on abundantly available, environmentally friendly, low-cost and ready-for-use Nutraceutical Industrial Cumin Seed Spent (NICUS) as an innovative adsorbent for bioremediation of a bisazo Acid Red 119 (AR119) dye, a probable mutagen from textile industrial effluents (TIEs). The experiment at the laboratory scale is designed to suit the concepts of sustainability and valorisation under the domain of circular economy. The experimental qe value obtained was 96.00 mg g−1. The optimised conditions of parameters are as follows: pH of 2; adsorption time, 210 min; adsorbent dosage, 0.300 g L−1; particle size, 175 µM; initial dye concentration, 950 mg L−1; orbital shaking, 165 rpm and temperature, 50 °C, producing an impressive value of 748 mg of dye adsorbing on 1 g of dry NICUS. The adsorption capacity of NICUS obtained from the quadratic model developed for process optimisation gave values of 748 mg g−1. As a prelude to commercialisation, five variables that affect the adsorption process were experimentally studied. For the feasibility and efficiency of the process, a two-level fractional factorial experimental design (FFED) was applied to identify variables that influence the adsorption capacity of NICUS. The identified variables were applied to scale experiments by three orders. Nine isotherm models were used to analyse the adsorption equilibrium data. The Vieth–Sladek adsorption isotherm model was found to be the best fit. The pseudo-second-order reaction was the appropriate mechanism for the overall rate of the adsorption process. Mechanistic studies related to mass transfer phenomena were more likely to be dominant over the diffusion process. Techniques such as SEM, FTIR and CHN analysis were used to characterise NICUS. The dye-adsorbed NICUS obtained as “sludge” was used as a reinforcing material for the fabrication of composites using plastic waste. The physicomechanical and chemical properties of thermoplastic and thermoset composite using dye-adsorbed NICUS were evaluated and compared with NICUS composites. Prospects of integrating Small and Medium Enterprises (SMEs) into the circular economy of Nutraceutical Industrial Spent (NIS) are discussed

Adsorption of ethidium bromide from aqueous solution onto nutraceutical industrial fennel seed spent: Kinetics and thermodynamics modeling studies

Dye pollutants from research laboratories are one of the major sources for environmental contamination. In the present study, a nutraceutical industrial fennel seed spent (NIFSS) was explored as potential adsorbent for removal of ethidium bromide (EtBr) from aqueous solution. The adsorbent was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Through batch experiments, the operating variables like initial dye concentration, adsorbent dosage, temperature, contact time, and pH were optimized. Equilibrium data were analyzed using three number of two-parameter and six number of three-parameter isotherm models. The adsorption kinetics was studied using pseudo-first order and pseudo-second order. The diffusion effects were studied by film diffusion, Webber–Morris, and Dumwald–Wagner diffusion models. The thermodynamic parameters; change in enthalpy (ΔHº), entropy (ΔSº), and Gibbs free energy (ΔGº) of adsorption system were also determined and evaluated

Kinetic and isotherm modeling for acid blue 113 dye adsorption onto low-cost nutraceutical industrial fenugreek seed spent

The present study reports about the use of fenugreek seed spent as a new and efficient biosorbent for the removal of acid blue 113 dye from aqueous media and textile industrial effluent. The spent is a low-cost by-product of nutraceutical industry. The effects of various process parameters of adsorption, such as pH, initial dye concentration, adsorbent dose, adsorbent particle size, contact time and temperature onto nutraceutical industrial fenugreek seed spent (NIFGS) have been studied. Four numbers of two-parameter and six numbers of three-parameter isotherm models were used in the analysis of adsorption equilibrium data. Kinetic studies data conformed to pseudo-second-order model. Molecular diffusion studies were carried out using Weber-Morris, Dumwald-Wagner and film diffusion models. Change in enthalpy (Delta H degrees), entropy change (Delta S degrees) and Gibbs free energy change (Delta G degrees) of adsorption system indicated that the process is physisorption. Scanning electron microscopy, Fourier transform infrared spectroscopy and point of zero charge were used in characterizing the adsorbent. Fractional factorial experimental design and analysis of variance along with statistically developed model for adsorption helped to predict for a maximum adsorption of 661.5 mg g(-1) using NIFGS. Application of NIFGS to textile industrial effluent and scaling up of the experimental process by three orders gave encouraging results