Biosorption of a common micropollutant (methylene blue) from a water environment by chemically activated biomass of a widely available plant species (Pyracantha coccinea M. J. Roemer).

Recently, to protect the health of aquatic life and, indirectly, all living things, biomass-based substances have been increasingly applied as biosorbent materials to remove micropollutant agents from an aquatic environment. However, these studies are under development, and the search for more successful materials continues. Here, the biosorption of a common micropollutant, methylene blue, from an aquatic environment was investigated using the chemically activated biomass of a widely available plant species, Pyracantha coccinea M. J. Roemer. The biosorption efficiency of the biosorbent material was improved by optimizing the experimental conditions, including the contact time, micropollutant load, pH, and biosorbent material amount, and the highest performance was observed at t = 360 mins, C0 = 15 mg L-1, pH = 8 and m = 10 mg. The pseudo-second-order kinetics model and Freundlich isotherm model were in good agreement with the experimentally obtained results. The thermodynamic study suggested that the micropollutant biosorption was a favorable, spontaneous, and physical process. The micropollutant-biosorbent interaction mechanism was presented using SEM and FTIR studies. The maximum Langmuir biosorption capacity of the biosorbent was determined to be 156.674 mg g-1. The activation operation more than doubled the biosorption potential of the biosorbent material. Thus, the present study showed that the chemically activated plant biomass-based material could be a promising biosorbent for the effective removal of the micropollutant from water environment.

The biosorption of a common micropollutant, methylene blue, from a water environment was studied using chemically activated biomass of Pyracantha coccinea M. J. Roemer. The activation operation more than doubled the biosorption potential of the biosorbent material. It exhibited higher micropollutant biosorption performance compared to most other biosorbents. These results indicated that the chemically activated biomaterial could be a very effective biosorbent for the micropollutant biosorption from an aqueous medium.

An efficient biosorbent material for green remediation of contaminated water medium.

The discharge of large amounts of wastewater carrying various contaminants from many anthropogenic activities into the receiving water environment is a multidimensional issue negatively affecting the ecological system and natural balance in many ways. The removal of pollutants by the biologically-originated materials is an emerging area of interest due to profoundly their environmental friendliness, renewability, sustainability, readily availability, biodegradability, multiplicity, low (or no) economic cost, high affinity, capacity, and stability. In the present study, a popular ornamental plant, Pyracantha coccinea M. J. Roemer, was converted into a green sorbent material with the goal to effectively remove a widespread contaminant (synthetic dye, C. I. Basic Red 46) from synthetic wastewater. The physicochemical characteristics of the prepared biosorbent were determined by the instrumental analyses of FTIR and SEM. The batch experiments of various operational influence parameters were conducted to maximize the system efficiency. The wastewater remediation behavior by the material was investigated by the kinetics, thermodynamics, and isotherm experiments. The biosorbent had a non-uniform and rough surface architecture with a diversity of functional groups. The maximum remediation yield was achieved with the contact duration of 360 min, the pollutant load of 30 mg L-1, the pH of 8, and the biosorbent quantity of 10 mg (0.1 g L-1). The kinetics of the contaminant removal showed good agreement with the pseudo-second-order model. Thermodynamics study indicated that the treatment process was spontaneous and occurred by physisorption. Langmuir model fitted the isotherm data of the biosorption operation well and the maximum pollutant cleanup capacity of the material was determined to be 169.354 mg g-1. These outcomes showed that P. coccinea M. J. Roemer could be used as a promising material for low-cost and green treatment of wastewater.

In the current study, Pyracantha coccinea M. J. Roemer was converted into a novel alternative sorbent material that is low-cost and green with the goal to effectively remove C. I. Basic Red 46, a widespread synthetic dye contaminant, from wastewater. The results indicated that P. coccinea M. J. Roemer could be used as an efficient biosorbent material for the green remediation of contaminated water medium.

Application of biorefinery by-product of Nigella sativa L. herb for green treatment of synthetic dye impurity in aquatic environment: a circular economy based approach to water purification.

In this work, the performance of residual biomass of Nigella sativa L. plant from the process of bio-oil production toward the green removal of synthetic dye pollution from aquatic medium was systematically studied for the first time based on the circular economy strategy. The characterization of material was performed using Electron Microscope of Scanning and Infrared Spectrometer of Fourier Transform. The main process variables like pH, biosorbent amount, synthetic dye loading, and contact duration were optimized by the batch biosorption experiments to achieve the maximum remediation yield. The analyses of kinetics, equilibrium, and thermodynamics were conducted to understand the possible mechanism of purification. The experimental dynamics and equilibrium data were in better agreement with the pseudo-second-order and Langmuir models. For the targeted model synthetic dye compound (C. I. Basic Red 46), the biosorption capacity was obtained as 136.2 mg g-1 at the optimized conditions of pH of 8, biosorbent amount of 10 mg (100 mg L-1), synthetic dye loading of 30 mg L-1, and duration of 360 min. The treatment process was favorable, spontaneous, and physical. The characterization operation showed that the dye molecules were restrained on the rough surface of biosorbent. This study reveals that the reuse of herbal oil refinery residue as a biosorbent can present an economic, efficient, and eco-friendly option for the remediation of synthetic dye pollution in aqueous medium.

Here, by adopting the circular economy based approach, an exemplary study was conducted using the waste biomass of Nigella sativa L. left over from the bio-oil production process for the removal of synthetic dye pollution from water environment. N. sativa L. (Black seed, Ranunculaceae plant family) is an annual herb containing many different bioactive molecules. Mostly, the seed part of plant is widely used for domestic and industrial purposes (such as food, medicine, cosmetic, and biofuel) almost all over the world. Most of the bioactive compounds of plant are concentrated in the oil content of seed (30­38%). A huge amount of waste seed biomass remains after the extraction process to obtain this rich oil ingredient. The reuse of this vegetal oil refinery by-product as a biosorbent material for the remediation of synthetic dye pollution in aqueous environment has not been investigated so far. A cationic azo dye (C. I. Basic Red 46) extensively employed in the textile industry was selected as the model synthetic dye compound to test the treatment efficiency of novel biosorbent. The optimization, dynamics, equilibrium, thermodynamics, characterization, and comparison analyses were performed to evaluate the performance of synthetic dye removal of biosorbent from water medium. This work showed that the application of N. sativa L. oil refinery residue as a novel biosorbent could offer a promising option for the treatment of synthetic dye impurity in water medium.

A novel biowaste-based biosorbent material for effective purification of methylene blue from water environment.

The biowaste left over from the fixed oil biorefinery process of Nigella sativa L. plant was used as a new biosorbent for the biosorption of synthetic dye of methylene blue from water environment in this study. The main variables of biosorption operation such as methylene blue concentration, time, pH, and biosorbent amount were optimized by the batch-type experiments. The characterization, kinetics, equilibrium, and thermodynamics works were conducted to show the nature of methylene blue biosorption. The studies of Fourier transform infrared spectroscopy and Scanning electron microscopy indicated that the biosorbent possessed an inhomogeneous surface morphology including many cavities and protuberances, and a rich functional group profile. The optimum values of operating variables studied for the biosorption of methylene blue were determined as methylene blue concentration of 15 mg L-1, time of 360 min, pH of 8, and biosorbent amount of 10 mg. The experimental data of methylene blue biosorption followed the kinetics and isotherm models of pseudo-second-order (R2: 0.98, AdjR2: 0.98, and RMSE: 8.97) and Dubinin-Radushkevich (R2: 0.99, AdjR2: 0.98, and RMSE: 6.84), respectively, based on the statistical tests of coefficient of determination (R2), adjusted coefficient of determination (AdjR2), and root mean squared error (RMSE). The biosorption of methylene blue was a physical, spontaneous, and energetically favorable process (EDR: 3.48 kJ mol-1 and ΔG°: (-14.51) - (-10.02) kJ mol-1). This residual biological material from the fixed oil biorefinery process exhibited higher biosorption performance (187.46 mg g-1) than own unrefined (virgin) form and its modified, activated, and composite forms and many other sorbents reported in the literature. Hereby, the current work showed that this novel biowaste-based material could be used as an environmentally and economically promising biosorbent to effectively purify methylene blue from aquatic environment.

Nigella sativa L. (black cumin) is a well-known annual medicinal and aromatic plant from the family of Ranunculaceae. Its seed part has a rich profile containing a wide variety of valuable compounds (fixed oil, carbohydrates, proteins, vitamins, pigments, essential oil, various bioactive substances, etc.), which are widely used in many fields such as cosmetics, food, medicine, and biofuel. After the refinery process to obtain these valuable compounds, a large amount of waste biomass remains. Considering the circular bioeconomy motion, a novel study was conducted on the use of biowaste left over from the fixed oil biorefinery process of N. sativa L. in the field of synthetic dye biosorption in the current work. The synthetic dye of methylene blue was used as a model to test the biosorption behavior of this novel biowaste-based biosorbent material. The main variables of biosorption operation such as synthetic dye concentration, time, pH, and biosorbent amount were optimized by the batch-type experiments. The characterization, kinetics, equilibrium, and thermodynamics studies were performed to show the nature of methylene blue biosorption operation.This residual biological material from the fixed oil biorefinery process exhibited higher biosorption performance than own unrefined (virgin) form and its modified, activated, and composite forms and many other sorbents reported in the literature. Hereby, the current work showed that this novel biowaste-based material could be used as an environmentally and economically promising biosorbent to effectively purify methylene blue from aquatic environment.

A renewable biosorbent material for green decontamination of heavy metal pollution from aquatic medium: a case study on manganese removal.

In this study, a renewable biosorbent material was prepared from biological waste of widespread coastal plant, Zostera marina and employed for the biosorption of heavy metal pollution from water environment in green way. Manganese was selected as a model heavy metal to evaluate the treatment efficiency of prepared biosorbent. The batch biosorption behavior of biosorbent was investigated by the characterization, parameters evaluation, kinetic and equilibrium studies. The characterization study showed that the biosorbent has a rough surface and various binding groups for the heavy metal ions. The heavy metal concentration of 30 mg L-1, time of 60 min, pH of 6 and biosorbent amount of 10 mg were determined as the optimum biosorption conditions. The pseudo-second-order equation was found to be the best among kinetic models applied. The equilibrium data were best explained by Freundlich isotherm. The maximum biosorption efficiency based on Langmuir model was predicted as 58.426 mg g-1. Hence, the current work presents a renewable alternative biosorbent substance for the green treatment of heavy metal pollution from water medium.

Sustainable environmental remediation approach for biocide removal from water medium: a model biosorption study using activated biological waste.

Within the scope of sustainable environmental remediation approach, a biosorbent prepared from the waste of Zostera marina coastal plant with chemical activation was used to effectively remove malachite green as a common biocidal agent from water environment in this work. The biocide treatment ability of activated biosorbent was interpreted through the characterization, optimization, equilibrium, thermodynamic, and kinetic studies. The characterization research showed that the biosorbent has an uneven surface and various active groups for the retention of biocide molecules. Langmuir isotherm was found to be the most appropriate model for the experimental equilibrium data. The maximum monolayer biosorption capacity was obtained as 103.834 mg g-1 under the optimum conditions (time of 6 h, pH of 4, temperature of 25 °C, biosorbent amount of 10 mg, and biocide concentration of 15 mg L-1). The biosorption system was determined to be spontaneous and exothermic in thermodynamic aspect. The experimental kinetic data were best described by the pseudo-second-order model. All these results indicated that the activated biological residue could be used as an environmentally friendly and effective biosorbent for the biocide removal from water environment in a sustainable way.

An economical and effective alternative to commercial activated carbon for treatment of synthetic dye pollution in aquatic environment: surfactant modified waste product of Zostera marina.

In this study, a novel biosorbent material was created from the waste product of Zostera marina with the surfactant modification (Hexadecyltrimethylammonium bromide) and tried as a potential alternative to commercial (powdered) activated carbon for the treatment of synthetic dye (Fast green FCF, triarylmethane (anionic) type) pollution in aquatic environment. The treatment capability of biosorbent material was evaluated by the parameter optimization, kinetic, thermodynamic, equilibrium and characterization experiments. The optimum treatment conditions were found to be pH of 3, biosorbent amount of 10 mg, synthetic dye concentration of 15 mg L-1, temperature of 45 °C and operation time of 360 min. It was determined that Elovich model was the most suitable model among the models used to define the biosorption kinetic data. The synthetic dye treatment process was endothermic and spontaneous. Freundlich model best explained the biosorption isotherm data. The biosorbent has very heterogeneous surface with the different functional groups. The treatment capabilities of prepared biosorbent and activated carbon under the same operating conditions were calculated to be 163.075 and 110.635 mg g-1, respectively. Hereby, these experimental findings show that the synthesized eco-friendly and low-cost biosorbent can be a powerful alternative to commercial activated carbon for the purification of synthetic dye pollution in water environment.

Purification of malachite green as a model biocidal agent from aqueous system by using a natural widespread coastal biowaste (Zostera marina).

The present paper aimed to perform an environmentally friendly and effective study on the purification of biocidal material using bioremediation technique, and in this context, a natural widespread coastal biowaste (Zostera marina) was applied to remove a model biocide from aqueous system. Herein, malachite green was selected as a common agent to evaluate the biosorption efficiency of waste biomaterial. The bioremediation properties of biosorbent were studied in a controlled batch experiment system by the optimization practice of operating parameters like biosorbent quantity, medium pH, time, pollutant concentration and temperature, and kinetic, thermodynamic, equilibrium, and characterization operations. The optimum operating conditions were considered as 10 mg, 4, 6 h, 15 mg L-1, and 25 °C, respectively. Elovich and Langmuir were found to be the best-fitted models, describing the experimental biosorption data. Thermodynamic study revealed a favorable nature of the cleanup process. The characterization analysis indicated the presence of various functional groups on the layered biosorbent surface involved on the pollutant treatment. The untreated biosorbent showed a good biocide purification performance with a value of 97.584 mg g-1, and it could thus be employed as an eco-friendly and cost-effective cleaning agent in environmental bioremediation studies.

An Effectual Biosorbent Substance for Removal of Manganese Ions from Aquatic Environment: A Promising Environmental Remediation Study with Activated Coastal Waste of Zostera marina Plant.

In the present research paper, a biosorptive remediation practice for an aqueous medium sample polluted with manganese ions was implemented using the activated coastal waste of the Zostera marina plant. This is the first report in the literature on the utilization of current modified biological waste as a biosorbent substance for the removal of manganese ions from the water environment. The analyses of biosorbent characterization, environmental condition, kinetic, equilibrium, and comparison were performed to introduce the ability of prepared biosorbent for the removal of manganese from the aquatic medium. The biosorbent matter has a rough surface with numerous cavities and cracks and various functional groups for the biosorption of manganese. The environmental conditions significantly affected the manganese purification process, and the optimum working conditions were determined to be biosorbent quantity of 10 mg, pH of 6, manganese concentration of 30 mg L-1, and time of 60 min. The pseudo-second-order model best explained the kinetic data of biosorption operation. The biosorption equilibrium data were best described by the Freundlich isotherm. According to the Langmuir equilibrium model, the maximum purification potency was estimated to be 120.6 mg g-1. The comparison work revealed that the activated coastal waste of the Z. marina plant could be utilized as an effectual and promising biosorbent substance for the remediation of an aquatic environment contaminated with manganese ions.

A Clinical Experience with Decompressive Craniectomy.

AIM: To investigate the patients who underwent decompressive craniectomy (DC) for trauma or cerebrovascular disease, and to determine the most suitable treatment protocol for those patients. MATERIAL AND METHODS: Overall, 32 patients with trauma or cerebrovascular disease underwent DC. Clinical, radiological and surgical data of surviving patients was retrospectively analysed. The occurence of favourable and unfavourable outcomes during the course of their treatment were recorded. RESULTS: We detected ventriculomegaly in nine out of the 32 patients (9/32, 28.1%) after DC. Of these nine, four patients (4/9, 44.4%) underwent shunt surgery. Cranioplasty performed in 29 of the 32 patients caused epidural hygroma in 13 of them (13/29, 44.8%). Of these 13 patients, three underwent surgery because of progressive increase in the size of hygromas. In the remaining patients, the epidural hygromas regressed spontaneously. Glasgow coma score (GCS) before and after DC surgery (p=0.011 and p=0.006, respectively), timing of cranioplasty (p=0.028), midline shift (p=0.048) and craniectomy size (p=0.047) were significantly associated with ventriculomegaly. CONCLUSION: Lower GCS, delayed cranioplasty, greater midline shift and larger craniectomy size were found to be associated with hydrocephalus after DC. To avoid hydrocephalus, it may be beneficial to perform shunt surgery first followed by cranioplasty in a single surgical procedure. Additionally, epidural hygromas frequently encountered after a cranioplasty that should be considered and followed up carefully.

A low-cost and eco-friendly biosorbent material for effective synthetic dye removal from aquatic environment: characterization, optimization, kinetic, isotherm and thermodynamic studies.

A novel biosorbent was prepared by the surface modification of Zostera marina L. bioresidues and used for the removal of model synthetic dye, methylene blue from aqueous medium in this study. Taguchi design of experiment (DoE) methodology was employed to investigate the influence of significant operational parameters (reaction time, pH of medium and dye concentration) on the biosorption process and to develop a mathematical model for the estimation of biosorption potential of biosorbent. The percentage contribution of each of these process variables on the dye biosorption was found to be 9.03%, 1.95% and 88.84%, respectively. The dye biosorption capacity under the obtained optimum environmental conditions (reaction time of 120 min, pH of 8 and dye concentration of 15 mg L-1) was estimated to be 140.154 mg g-1 (R2: 99.83). This value was very close to the experimentally obtained dye removal performance value (140.299 mg g-1). These findings indicated the high ability of Taguchi DoE technique in the optimization and simulation of dye biosorption system. The kinetic and equilibrium modeling studies showed that the pseudo-second-order and Langmuir models were the best models for the elucidation of dye removal behavior of biosorbent. Besides, the performance of dye decontamination system was evaluated using the pseudo-second-order kinetic parameters. The thermodynamic analyses displayed that the dye biosorption was a feasible, spontaneous and exothermic process. For large scale dye purification applications, a single-stage batch biosorption system was also designed using the mathematical modeling data. All these results revealed that Z. marina L. bioresidues could be used as a promising alternative biosorbent material for the effective and eco-friendly dye biosorption systems.

Taguchi DoE methodology for modeling of synthetic dye biosorption from aqueous effluents: parametric and phenomenological studies.

Biosorption technology has been acknowledged as one of the most successful treatment approaches for colored industrial effluents. The problems such as its high manufacturing cost and poor regeneration capability in the use of activated carbon as a biosorbent have prompted the environmental scientists to develop alternative biosorbent materials. In this context, as a sustainable green generation alternative biosorbent source, the discarded seed biomass from pepper (Capsicum annuum L.) processing industry was explored for the biotreatment of colored aqueous effluents in this study. To test the wastewater cleaning ability of biosorbent, Basic red 46 was selected as a typical model synthetic dye. Taguchi DoE methodology was employed to study the effect of important operational parameters, contact time, pH and synthetic dye concentration, on the biosorption process and to develop a mathematical model for the estimation of biosorption potential of biosorbent. The percentage contribution of each of these process variables on the dye biosorption was found to be 19.31%, 41.39%, and 38.74%, respectively. The biosorption capacity under the optimum environmental conditions, contact time of 360 min, pH of 8 and dye concentration of 30 mg L-1, was estimated to be 92.878 mg g-1 (R2: 99.45). This value was very close to the experimentally obtained dye removal performance value (92.095 mg g-1). These findings indicated the high ability of Taguchi DoE technique in the optimization and simulation of dye biosorption system. The kinetic and equilibrium modeling studies showed that the pseudo-second-order and Langmuir models were the best models for the elucidation of dye removal behavior of biosorbent. The thermodynamic studies displayed that the dye biosorption was a feasible, spontaneous and exothermic process. This parametric and phenomenological survey revealed that the discarded pepper seed biomass can be introduced as a potential and efficient biosorbent for the bioremediation of colored industrial effluents.

WITHDRAWN: An integrated approach towards sustainable wastewater treatment and biofuel production: A phytotechnological study on defatted residual seed biomass of Datura stramonium L.

Available online 1 March 2019. This article has been withdrawn at the request of the editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

WITHDRAWN: A combinatorial bioinnovative approach integrating synthetic dye bioremediation and bioenergy production using waste pepper seed biomass.

A combinatorial study integrating synthetic dye bioremediation and biodiesel production using discarded pepper seed biomass was performed for a cleaner and more sustainable environment/energy in the present work. The vegetal oil was extracted from the pepper seed biomass and the defatted residual biomass was mainly investigated as a sustainable green generation alternative biosorbent source for the treatment of colored aqueous effluents. To test the wastewater cleaning ability of biosorbent, basic red 46 was selected as a common harmful model synthetic dye. The kinetic, equilibrium and thermodynamic modeling studies were performed to elucidate the dye biosorption behavior of biosorbent. Besides, the performance of dye bioremediation system was evaluated using the kinetic modeling parameters, and for large scale dye purification applications, a single-stage batch bioreactor system was designed using the mathematical modeling data. The operating conditions significantly affected the biosorption process. The pseudo-second-order and Freundlich models provided the best fit to the kinetic and isotherm data, respectively. The thermodynamic studies showed that the dye biosorption was a feasible and spontaneous process. The maximum dye biosorption capacity of biosorbent based on Langmuir model was predicted as 82.019 mg g-1. As compared many other biosorbents reported in literature for the same contaminant, this high value revealed a great potential of biosorbent for the dye removal from aqueous medium. Thus, the present study showed that the discarded pepper seed biomass could be employed as a highly efficient as well as cost-effective material for both dye bioremediation and biodiesel production in a sustainable manner.

Bioremediation potential of waste biomaterials originating from coastal Zostera marina L. meadows for polluted aqueous media with industrial effluents.

The studies on novel and efficient biosorbent materials for the promotion of environmental and economic sustainability have been become an up-to-date attempt by scientists for the removal of synthetic dyes from industrial effluents. The biosorbents prepared from biomass based resources are emerging as an alternative promising material for the environmental clean-up because of their low-cost, renewability, eco-friendly, easy availability and so forth characteristics. Hence, for the first time, the biosorption performance of abundantly available natural biowastes originating from coastal Zostera marina L. meadows was explored for the biotreatment of colored industrial effluents in the present study. The biosorption properties of biosorbent for methylene blue as a representative synthetic industrial dye were investigated by means of the operational parameters optimization, kinetic, isotherm, thermodynamic and characterization studies. The operating conditions significantly affected the biosorption process and the optimal values were determined as pH of 8, biosorbent dosage of 10 mg, dye concentration of 15 mg L-1 and contact time of 120 min. Elovich and Freundlich models provided the best fit to the kinetic and isotherm data compared with other applied models, respectively. The negative change in free energy (-10.682 to -8.466 kJ mol-1) indicated a thermodynamically feasible and spontaneous process. The characterization analysis showed that the biosorbent has appropriate chemical and physical properties for the dye biosorption. Thus, the present study displayed that the waste materials originating from coastal Z. marina L. meadows can be applied as a highly efficient as well as cost-effective green generation biosorbent for the clean-up of colored aquatic media.

The Role of Bone Scintigraphy in Determining Spinal Fusion after Spinal Stabilisation Surgery.

AIM: To evaluate the usefulness of bone scintigraphy in spinal fusion surgery. MATERIAL AND METHODS: This retrospective study included 21 patients who had undergone previous anterior or posterior spinal fusion procedures, or both. Implant failure, fusion failure and adjacent segment disease were the evaluated pathological parameters. Scintigraphic data from all patients were evaluated with intraoperative observational data, radiological data and clinical data. RESULTS: Radiological evaluation revealed adjacent segment disease in 5 patients (23.8%), implant failure in 2 (9.5%), and fusion failure in 1 (4.8%). Scintigraphic evaluation of operating segments revealed pseudo-fusion in 3 patients (14.3%) and fusions in 18 (85.7%). Reoperations were performed in 9 patients (42.9%): in 5 (23.8%) because of adjacent segment disease, and in 4 (19.0%) because they requested removal of the implants. Two patients (9.5%) with implant failure did not undergo reoperation because their scintigraphic data were consistent with fusion and they were almost symptom free, with lower Visual Analogue Scale (VAS) scores. The VAS scores of the rest of the patients were significantly reduced after the reoperations (p < 0.001). CONCLUSION: Bone scintigraphy may be helpful for surgeons in planning appropriate surgical revision strategy by giving proper data about spinal fusion at least one year after the initial surgery.

Bioremediation potential of a widespread industrial biowaste as renewable and sustainable biosorbent for synthetic dye pollution.

In this study, a model synthetic azo dye (Basic red 46) bioremoval by Carpinus betulus sawdust as inexpensive, eco-friendly, and sustainable biosorbent from aqueous solution was examined in a batch biosorption system. The effective environmental parameters on the biosorption process, such as the value of pH, amount of biosorbent, initial dye concentration and contact time were optimized using classical test design. The possible dye-biosorbent interaction was determined by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The equilibrium, thermodynamic, and kinetic studies for the biosorption of Basic red 46 onto the sawdust biomass were performed. In addition, a single-stage batch dye biosorption system was also designed. The dye biosorption yield of biosorbent was significantly influenced by the change of operating variables. The experimental data were best described by the Freundlich isotherm model and both the pseudo-first-order kinetic and the pseudo-second-order kinetic models. Thermodynamic research indicated that the biosorption of dye was feasible and spontaneous. Based on the Langmuir isotherm model, the biosorbent was found to have a maximum biosorption potential higher than many other biosorbents in the literature (264.915 mg g-1). Thus, this investigation presents a novel green option for the assessment of waste sawdust biomass as a cheap and effective biosorbent material.

A natural macroalgae consortium for biosorption of copper from aqueous solution: Optimization, modeling and design studies.

In this study, the capacity of a natural macroalgae consortium consisting of Chaetomorpha sp., Polysiphonia sp., Ulva sp. and Cystoseira sp. species for the removal of copper ions from aqueous environment was investigated at different operating conditions, such as solution pH, copper ion concentration and contact time. These environmental parameters affecting the biosorption process were optimized on the basis of batch experiments. The experimentally obtained data for the biosorption of copper ions onto the macroalgae-based biosorbent were modeled using the isotherm models of Freundlich, Langmuir, Sips and Dubinin-Radushkevich and the kinetic models of pseudo-first-order, pseudo-second-order, Elovich and Weber and Morris. The pseudo-first-order and Sips equations were the most suitable models to describe the copper biosorption from aqueous solution. The thermodynamic data revealed the feasibility, spontaneity and physical nature of biosorption process. Based on the data of Sips isotherm model, the biosorption capacity of biosorbent for copper ions was calculated as 105.370 mg g-1 under the optimum operating conditions. A single-stage batch biosorption system was developed to predict the real-scale-based copper removal performance of biosorbent. The results of this investigation showed the potential utility of macroalgae consortium for the biosorption of copper ions from aqueous medium.

Application of a novel phyco-composite biosorbent for the biotreatment of aqueous medium polluted with manganese ions.

A composite phyco-biomass including four different marine macroalgae species (Chaetomorpha sp., Polysiphonia sp., Ulva sp., and Cystoseira sp.) was evaluated as a novel biosorbent for the biosorption of manganese ions from aqueous solution. The experimental studies were performed to optimize the operational factors including solution pH, biosorbent amount, initial manganese concentration, and reaction time in a batch-mode biosorption system. The removal yield of the biosorbent for manganese ions increased with increasing pH, manganese ion concentration, and reaction time, while it decreased as the biosorbent dose increased. The obtained kinetic data indicated that the removal of manganese ions by the biosorbent was best described by the pseudo-second-order model and the pore diffusion also contributed to the biosorption process. The results of isotherm and thermodynamic studies showed that the Freundlich model represented the biosorption equilibrium data well and this biotreatment system was feasible, spontaneous, and physical. The maximum manganese uptake capacity of used biosorbent was found to be 55.874 mg g-1. Finally, a single-stage batch manganese biosorption system was designed and its kinetic performance was evaluated. All these findings revealed that the prepared composite macroalgae biosorbent has a fairly good potential for the removal of manganese ions from the aqueous medium.

An ecofriendly approach for bioremediation of contaminated water environment: Potential contribution of a coastal seaweed community to environmental improvement.

High levels of heavy metals like copper ions in many industrial based effluents lead to serious environmental and health problems. Biosorption is a potential environmental biotechnology approach for biotreatment of aquatic sites polluted with heavy metal ions. Seaweeds have received great attention for their high bioremediation potential in recent years. However, the co-application of marine macroalgae for removal of heavy metals from wastewater is very limited. Thus, for the first time in literature, a coastal seaweed community composed of Chaetomorpha sp., Polysiphonia sp., Ulva sp. and Cystoseira sp. species was applied to remove copper ions from synthetic aqueous medium in this study. The biosorption experiments in batch mode were conducted to examine the effects of operating variables including pH, biosorbent amount, metal ion concentration and contact time on the biosorption process. The biosorption behavior of biosorbent was described by various equilibrium, kinetic and thermodynamic models. The biosorption of copper ions was strongly influenced by the operating parameters. The results indicated that the equilibrium data of biosorption were best modeled by Sips isotherm model. The values of mean free energy of biosorption computed from Dubinin-Radushkevich isotherm model and the standard Gibbs free energy change indicated a feasible, spontaneous and physical biotreatment system. The pseudo-second-order rate equation successfully defined the kinetic behavior of copper biosorption. The pore diffusion also played role in the control of biosorption process. The maximum copper uptake capacity of biosorbent was found to be greater than those of many other biosorbents. The obtained results revealed that this novel biosorbent could be a promising material for copper ion bioremediation implementations.