Buhani, Suharso, Nurul Miftahza, D. Permatasari, Sumadi
In this research, biomass modification of Nannochloropsis sp. with surfactant cetyltrimethylammonium bromide (CTAB) through a cation exchange reaction to produce adsorbent Nannochloropsis sp.-cetyltrimethylammonium bromide (AlgN-CTAB) has been carried out. Biomass modification of Nannochloropsis sp. by CTAB has been successfully carried out through confirmation from the analysis data produced by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDX). AlgN-CTAB adsorbent has been tested for its adsorption ability against anionic dye of methyl orange (MO) in solution by way of a sequence of experiments by the batch method. The optimum conditions for MO removal from the solution occurred at an adsorbent quantity of 0.1 g, pH of 5, and an interaction time of 60 min. MO adsorption kinetic data by AlgN and AlgN-CTAB tended to take the kinetic model of pseudo-second-order (PSO) with PSO rate constant ( k 2 ) values of 0.56 and 2.17 g mg-1 min-1, serially. The MO adsorption isotherm pattern by AlgN tends to take the Freundlich adsorption isotherm, whereas in AlgN-CTAB it follows the Langmuir and Dubinin-Radushkevich adsorption isotherms. The results of the adsorption-desorption of MO by AlgN-CTAB with 4 repetition cycles resulted in % removal of MO > 80 % . The AlgN-CTAB adsorbent can be used repeatedly and is very effective in absorbing MO in water.
本研究以表面活性剂十六烷基三甲基溴化铵（CTAB）为原料，通过阳离子交换反应对Nannochloropsis sp.进行了生物量改性，制备了吸附剂Nannochlopsis sp.-十六烷基三三甲铵（AlgN-CTAB）。通过傅立叶变换红外光谱（FTIR）、扫描电子显微镜和能量色散X射线光谱（SEM-EDX）的分析数据证实，CTAB成功地对Nannochloropsis sp.进行了生物量改性。采用分批法对AlgN-CTAB吸附剂对溶液中甲基橙（MO）阴离子染料的吸附性能进行了测试。从溶液中去除MO的最佳条件是吸附剂量为0.1 g、 pH为5，相互作用时间为60 AlgN和AlgN-CTAB的最小MO吸附动力学数据倾向于采用伪二阶（PSO）动力学模型，PSO速率常数（k2）分别为0.56和2.17 g mg-1 min-1，连续。AlgN对MO的吸附等温线倾向于Freundlich吸附等温线，而在AlgN-CTAB中则遵循Langmuir和Dubinin-Radushkevich吸附等温线。AlgN-CTAB对MO的吸附-解吸4个重复循环的结果表明，MO的去除率>80%。AlgN-CTAB吸附剂可以重复使用，对水中MO的吸收非常有效。
{"title":"Improved Adsorption Capacity of Nannochloropsis sp. through Modification with Cetyltrimethylammonium Bromide on the Removal of Methyl Orange in Solution","authors":"Buhani, Suharso, Nurul Miftahza, D. Permatasari, Sumadi","doi":"10.1155/2021/1641074","DOIUrl":"https://doi.org/10.1155/2021/1641074","url":null,"abstract":"In this research, biomass modification of Nannochloropsis sp. with surfactant cetyltrimethylammonium bromide (CTAB) through a cation exchange reaction to produce adsorbent Nannochloropsis sp.-cetyltrimethylammonium bromide (AlgN-CTAB) has been carried out. Biomass modification of Nannochloropsis sp. by CTAB has been successfully carried out through confirmation from the analysis data produced by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDX). AlgN-CTAB adsorbent has been tested for its adsorption ability against anionic dye of methyl orange (MO) in solution by way of a sequence of experiments by the batch method. The optimum conditions for MO removal from the solution occurred at an adsorbent quantity of 0.1 g, pH of 5, and an interaction time of 60 min. MO adsorption kinetic data by AlgN and AlgN-CTAB tended to take the kinetic model of pseudo-second-order (PSO) with PSO rate constant (\u0000 \u0000 \u0000 \u0000 k\u0000 \u0000 \u0000 2\u0000 \u0000 \u0000 \u0000 ) values of 0.56 and 2.17 g mg-1 min-1, serially. The MO adsorption isotherm pattern by AlgN tends to take the Freundlich adsorption isotherm, whereas in AlgN-CTAB it follows the Langmuir and Dubinin-Radushkevich adsorption isotherms. The results of the adsorption-desorption of MO by AlgN-CTAB with 4 repetition cycles resulted in % removal of \u0000 \u0000 MO\u0000 >\u0000 80\u0000 %\u0000 \u0000 . The AlgN-CTAB adsorbent can be used repeatedly and is very effective in absorbing MO in water.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49589107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study is attempted to extract the amorphous silica composites using the combined HNO3 leaching-calcination (600°C/6 h) method from corn stalk harvested in Bishoftu, Ethiopia, owning to its profuse dumping, less cost, and negative environmental implications. The resultant composite characteristics such as amorphous nature are connected via the grain boundary which produces an agglomerated structure that has a disordered morphology, and the presence of siloxane and silanol groups, as well as additional functional groups, is reported. The synthesized product is applied in the removal of oil from synthetic oily wastewater (SYOWW) using batch mode delivering a maximum oil removal of up to 99%. The outcome of the study features the potential acclimatization of the Ethiopian corn stalk as a substitute precursor for the production of silica composites which has a potential oil adsorption capacity that can be used for oil spill cleanup.
{"title":"Facile Synthesis of Silica Composites with Oil Sorption Efficiency from a Vital Agricultural Waste of Corn Stalk Cultivated in Bishoftu, Ethiopia","authors":"M. Kamaraj, Sudarshan Kamble, S. Sonia","doi":"10.1155/2021/7205135","DOIUrl":"https://doi.org/10.1155/2021/7205135","url":null,"abstract":"This study is attempted to extract the amorphous silica composites using the combined HNO3 leaching-calcination (600°C/6 h) method from corn stalk harvested in Bishoftu, Ethiopia, owning to its profuse dumping, less cost, and negative environmental implications. The resultant composite characteristics such as amorphous nature are connected via the grain boundary which produces an agglomerated structure that has a disordered morphology, and the presence of siloxane and silanol groups, as well as additional functional groups, is reported. The synthesized product is applied in the removal of oil from synthetic oily wastewater (SYOWW) using batch mode delivering a maximum oil removal of up to 99%. The outcome of the study features the potential acclimatization of the Ethiopian corn stalk as a substitute precursor for the production of silica composites which has a potential oil adsorption capacity that can be used for oil spill cleanup.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46142114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Montree Thongkam, Jinnaput Saelim, B. Boonchom, S. Seesanong, Kittichai Chaiseeda, N. Laohavisuti, K. Bunya-atichart, W. Boonmee, D. Taemchuay
The search for sustainable resources remains a subject of global interest. Calcium acetate used in many fields was prepared using waste scallop shell as a raw material, and its physicochemical properties were investigated. The waste scallop shells were transformed to calcium acetate compounds by reactions with four acetic acid concentrations at ambient temperature until the completely dried powder is obtained. The maximum yield of 87% with short reaction time at a low temperature was observed in the reaction of 60%w/w acetic acid with scallop shells. Thermal transformation reactions of all prepared calcium acetate samples revealed temperature conditions for heating to produce other advanced materials. FTIR and XRD results confirmed the purity and solid phase of all prepared calcium acetate samples, and they were compared with those of literatures and found to be well consistent. The obtained timber-like particles have different sizes depending on the acetic acid concentration. This work reports an easy and low-cost method with no environmental effect to produce cheap calcium products to be used in the industry.
{"title":"Simple and Rapid Synthesis of Calcium Acetate from Scallop Shells to Reduce Environmental Issues","authors":"Montree Thongkam, Jinnaput Saelim, B. Boonchom, S. Seesanong, Kittichai Chaiseeda, N. Laohavisuti, K. Bunya-atichart, W. Boonmee, D. Taemchuay","doi":"10.1155/2021/6450289","DOIUrl":"https://doi.org/10.1155/2021/6450289","url":null,"abstract":"The search for sustainable resources remains a subject of global interest. Calcium acetate used in many fields was prepared using waste scallop shell as a raw material, and its physicochemical properties were investigated. The waste scallop shells were transformed to calcium acetate compounds by reactions with four acetic acid concentrations at ambient temperature until the completely dried powder is obtained. The maximum yield of 87% with short reaction time at a low temperature was observed in the reaction of 60%w/w acetic acid with scallop shells. Thermal transformation reactions of all prepared calcium acetate samples revealed temperature conditions for heating to produce other advanced materials. FTIR and XRD results confirmed the purity and solid phase of all prepared calcium acetate samples, and they were compared with those of literatures and found to be well consistent. The obtained timber-like particles have different sizes depending on the acetic acid concentration. This work reports an easy and low-cost method with no environmental effect to produce cheap calcium products to be used in the industry.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42272786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An ionic soil stabilizer (ISS) is used to reinforce clay soils because the ISS can regulate the hydration processes and microstructures of clays. To evaluate the regulation of ISS, natural bentonite was modified by ISS at different concentrations in this research. Water vapour adsorption and X-ray diffraction (XRD) were carried out to interpret the hydration mechanism of bentonite. Meanwhile, an associated analysis between hydration pore structures and hydration mechanisms was implemented through variation of pore characteristic tests at different relative humidities (RHs) to distinguish multiscale pore adsorption of water during the corresponding hydration process. In addition, the pore characteristics were studied via XRD, nitrogen adsorption, and mercury injection tests. Finally, the origins that adsorbed water and pore structures changed by adding ISS were discussed. The results showed that for calcium bentonite, the cations hydrated first in the range of 0 < RH < 0.45 ~ 0.55 , accompanied by the expansion of micropores. Then, adsorption occurred on the basal surface of the crystal layer in the range of 0.45 ~ 0.55 < RH < 0.8 ~ 0.9 , with water mainly adsorbed into the mesopores. With further hydration when RH > 0.8 ~ 0.9 , diffused double layer (DDL) water ceaselessly entered the macropores. Both adsorbed water and multiscale pore size decreased when ISS was added to bentonite. The origins of the reduction were the regulation of ISS to exchangeable cations and the basal surface of the crystal layer.
{"title":"Evolution of Pore Characteristics for Bentonite Modified by an Ionic Soil Stabilizer during Hydration Processes","authors":"Wei Huang, Zili Feng, Huanran Fu, W. Xiang","doi":"10.1155/2021/7777091","DOIUrl":"https://doi.org/10.1155/2021/7777091","url":null,"abstract":"An ionic soil stabilizer (ISS) is used to reinforce clay soils because the ISS can regulate the hydration processes and microstructures of clays. To evaluate the regulation of ISS, natural bentonite was modified by ISS at different concentrations in this research. Water vapour adsorption and X-ray diffraction (XRD) were carried out to interpret the hydration mechanism of bentonite. Meanwhile, an associated analysis between hydration pore structures and hydration mechanisms was implemented through variation of pore characteristic tests at different relative humidities (RHs) to distinguish multiscale pore adsorption of water during the corresponding hydration process. In addition, the pore characteristics were studied via XRD, nitrogen adsorption, and mercury injection tests. Finally, the origins that adsorbed water and pore structures changed by adding ISS were discussed. The results showed that for calcium bentonite, the cations hydrated first in the range of \u0000 \u0000 0\u0000 <\u0000 RH\u0000 <\u0000 0.45\u0000 ~\u0000 0.55\u0000 \u0000 , accompanied by the expansion of micropores. Then, adsorption occurred on the basal surface of the crystal layer in the range of \u0000 \u0000 0.45\u0000 ~\u0000 0.55\u0000 <\u0000 RH\u0000 <\u0000 0.8\u0000 ~\u0000 0.9\u0000 \u0000 , with water mainly adsorbed into the mesopores. With further hydration when \u0000 \u0000 RH\u0000 >\u0000 0.8\u0000 ~\u0000 0.9\u0000 \u0000 , diffused double layer (DDL) water ceaselessly entered the macropores. Both adsorbed water and multiscale pore size decreased when ISS was added to bentonite. The origins of the reduction were the regulation of ISS to exchangeable cations and the basal surface of the crystal layer.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41976341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mai Quan Doan, Nguyen Ha Anh, Hoang Van Tuan, N. C. Tu, N. H. Lam, Nguyen Tien Khi, Vu Ngoc Phan, P. D. Thang, Anh-Tuan Le
Multifunctional nanocomposites have received great attention for years; electron transfer (ET) is considered as an explanatory mechanism for enhancement of performance of these nanostructures. The existence of this ET process has been proved in many studies using either experimental or computational approaches. In this study, a ternary nanocomposite system of Ag/TiO2/GO was prepared to evaluate the performance enhancement in two experimental models: a physical model (i.e., surface-enhanced Raman scattering (SERS) sensor) and a chemical one (i.e., catalytic reduction reaction). The metal/semiconductor heterojunction between Ag and TiO2, as well as Ti-O-C bonds, has allowed plasmonic hot electrons to be transferred in the internal structure of the material. An investigation on the role of Ag content on the SERS sensing and catalytic reduction efficiency of Ag/TiO2/GO was performed in both models. Interestingly, they all resulted in the same optimal Ag content of 50 wt%. It was then further discussed to provide a convincing evidence for the plasmon-induced electron transfer phenomena in the Ag/TiO2/GO nanostructure. These findings also suggest a pathway to design and develop high-performance, cost-effective, facile-preparation, and eco-friendly multifunctional nanostructures for detecting and removing contaminants in environment.
{"title":"Improving SERS Sensing Efficiency and Catalytic Reduction Activity in Multifunctional Ternary Ag-TiO2-GO Nanostructures: Roles of Electron Transfer Process on Performance Enhancement","authors":"Mai Quan Doan, Nguyen Ha Anh, Hoang Van Tuan, N. C. Tu, N. H. Lam, Nguyen Tien Khi, Vu Ngoc Phan, P. D. Thang, Anh-Tuan Le","doi":"10.1155/2021/1169599","DOIUrl":"https://doi.org/10.1155/2021/1169599","url":null,"abstract":"Multifunctional nanocomposites have received great attention for years; electron transfer (ET) is considered as an explanatory mechanism for enhancement of performance of these nanostructures. The existence of this ET process has been proved in many studies using either experimental or computational approaches. In this study, a ternary nanocomposite system of Ag/TiO2/GO was prepared to evaluate the performance enhancement in two experimental models: a physical model (i.e., surface-enhanced Raman scattering (SERS) sensor) and a chemical one (i.e., catalytic reduction reaction). The metal/semiconductor heterojunction between Ag and TiO2, as well as Ti-O-C bonds, has allowed plasmonic hot electrons to be transferred in the internal structure of the material. An investigation on the role of Ag content on the SERS sensing and catalytic reduction efficiency of Ag/TiO2/GO was performed in both models. Interestingly, they all resulted in the same optimal Ag content of 50 wt%. It was then further discussed to provide a convincing evidence for the plasmon-induced electron transfer phenomena in the Ag/TiO2/GO nanostructure. These findings also suggest a pathway to design and develop high-performance, cost-effective, facile-preparation, and eco-friendly multifunctional nanostructures for detecting and removing contaminants in environment.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46774222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Nguyen, Xuan-Truong Nguyen, Duc-Trung Nguyen, H. Tran, Thi May Nguyen, T. Tran
Metal-organic framework composites, which are combined from metal-organic framework and advanced carbon material, have drawn great attention in many fields of application such as environmental remediation and catalysts. Within this paper, the carbon/MIL-53(Fe) composite was fabricated via an in situ synthesis, in which N-containing carbon dots (NCDs) were mixed with MOF precursors’ solutions under various ratios before going through the solvothermal stage. It was showed that the introduction of a certain amount of NCDs would affect characteristic features and improve the photocatalytic performance of final products. The optimal doping content of NCDs in NCD/MIL-53(Fe) composite was determined. SEM images showed that the M-140 appeared as hexagonal bipyramid-shaped crystals with an average size of 700 nm. Compared with pristine MIL-53(Fe), the M-140 was more visibly light-responsive, and its calculated band gap energy was approximately 2.3 eV. In addition, M-140 catalyst also displayed more excellent photocatalytic activity for Methylene Blue degradation in a pH range from 5 to 7. Under optimal conditions, MB was achieved within 60 minutes and the removal rate was nearly 100% after 5 cycles. The photocatalytic mechanism of the obtained NCD/MIL-53(Fe) composite was discussed.
{"title":"Effect of Nitrogen-Doped Carbon Dots (NCDs) on the Characteristics of NCD/MIL-53(Fe) Composite and Its Photocatalytic Performance for Methylene Blue Degradation under Visible Light","authors":"N. Nguyen, Xuan-Truong Nguyen, Duc-Trung Nguyen, H. Tran, Thi May Nguyen, T. Tran","doi":"10.1155/2021/5906248","DOIUrl":"https://doi.org/10.1155/2021/5906248","url":null,"abstract":"Metal-organic framework composites, which are combined from metal-organic framework and advanced carbon material, have drawn great attention in many fields of application such as environmental remediation and catalysts. Within this paper, the carbon/MIL-53(Fe) composite was fabricated via an in situ synthesis, in which N-containing carbon dots (NCDs) were mixed with MOF precursors’ solutions under various ratios before going through the solvothermal stage. It was showed that the introduction of a certain amount of NCDs would affect characteristic features and improve the photocatalytic performance of final products. The optimal doping content of NCDs in NCD/MIL-53(Fe) composite was determined. SEM images showed that the M-140 appeared as hexagonal bipyramid-shaped crystals with an average size of 700 nm. Compared with pristine MIL-53(Fe), the M-140 was more visibly light-responsive, and its calculated band gap energy was approximately 2.3 eV. In addition, M-140 catalyst also displayed more excellent photocatalytic activity for Methylene Blue degradation in a pH range from 5 to 7. Under optimal conditions, MB was achieved within 60 minutes and the removal rate was nearly 100% after 5 cycles. The photocatalytic mechanism of the obtained NCD/MIL-53(Fe) composite was discussed.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46415766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chitosan/bentonite composites (CSBT) prepared by physical gelation were tested for the adsorption of Cr (VI) from aqueous solutions in this work. The composites were prepared at a mass ratio from 2 : 1 to 1 : 2, and a composite of 1 : 1 was found to be most suitable for efficient Cr (VI) removal. The influencing parameters, including temperature, adsorbent dose, and pH, were statistically optimized using response surface methodology (RSM) for the removal of Cr (VI). The pH was found to be the limiting factor during the adsorption process, and under the optimal conditions, namely, adsorbent dose of 400 mg/L, pH = 3 , and temperature of 298 K, 87.61% Cr (VI) would be removed expectantly. The mechanism of Cr (VI) removal by CSBT was discussed, and the protonation of amino groups on chitosan followed by the combination of -NH3+ and anionic hexavalent chromium was the primary driving force. In addition, the removal of Cr (VI) onto CSBT was monolayer adsorption with a maximum adsorption capacity of 133.85 mg/g by the Langmuir isotherm. CSBT follows a pseudosecond-order kinetic model, and within 1.5 h, adsorption was observed to reach equilibrium. The calculated thermodynamic functions clarified that the adsorption process was exothermic and spontaneous below 312.60 K. CSBT could be regenerated after desorption by 0.5 mol/L NaOH solutions and exhibited superior reusability after six cycles. This study demonstrated composites of chitosan/bentonite as eco-friendly bioadsorbents for the removal of Cr (VI) from aqueous environments.
{"title":"Preparation and Characterization of Chitosan/Bentonite Composites for Cr (VI) Removal from Aqueous Solutions","authors":"J. Jia, Yanjun Liu, Shujuan Sun","doi":"10.1155/2021/6681486","DOIUrl":"https://doi.org/10.1155/2021/6681486","url":null,"abstract":"Chitosan/bentonite composites (CSBT) prepared by physical gelation were tested for the adsorption of Cr (VI) from aqueous solutions in this work. The composites were prepared at a mass ratio from 2 : 1 to 1 : 2, and a composite of 1 : 1 was found to be most suitable for efficient Cr (VI) removal. The influencing parameters, including temperature, adsorbent dose, and pH, were statistically optimized using response surface methodology (RSM) for the removal of Cr (VI). The pH was found to be the limiting factor during the adsorption process, and under the optimal conditions, namely, adsorbent dose of 400 mg/L, \u0000 \u0000 pH\u0000 =\u0000 3\u0000 \u0000 , and temperature of 298 K, 87.61% Cr (VI) would be removed expectantly. The mechanism of Cr (VI) removal by CSBT was discussed, and the protonation of amino groups on chitosan followed by the combination of -NH3+ and anionic hexavalent chromium was the primary driving force. In addition, the removal of Cr (VI) onto CSBT was monolayer adsorption with a maximum adsorption capacity of 133.85 mg/g by the Langmuir isotherm. CSBT follows a pseudosecond-order kinetic model, and within 1.5 h, adsorption was observed to reach equilibrium. The calculated thermodynamic functions clarified that the adsorption process was exothermic and spontaneous below 312.60 K. CSBT could be regenerated after desorption by 0.5 mol/L NaOH solutions and exhibited superior reusability after six cycles. This study demonstrated composites of chitosan/bentonite as eco-friendly bioadsorbents for the removal of Cr (VI) from aqueous environments.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47706377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Li Liu, Y. Rao, Changshun Tian, Tao Huang, Jiacheng Lu, Mei-dao Zhang, Min Han
To alleviate the environmental problem associated with rare earth wastewater, this research applied waste orange peel (OP) for the adsorption of La(III) and Y(III) from aqueous solution. The adsorption properties of orange peel are characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), and the participation of hydroxyl and other oxygen-containing groups that promote the physical-chemical interaction is verified. Batch adsorption results suggest that orange peel possesses a satisfactory adsorption performance for La(III) and Y(III). The optimal adsorption conditions were obtained at pH of 6, temperature of 40°C, appropriate dosage of 2 g/L and 3 g/L, contact time of 30 min, and initial ion concentration of 32 mg/L. Under the same condition, adsorption performance of La(III) is better than that of Y(III). The experimental data is well fitted by the Langmuir isotherm model with correlation coefficient R 2 > 0.9 and the minimum standard error values. Equilibrium results show that Langmuir monolayer adsorption capacity of La(III) and Y(III) onto orange peel is up to 37.61 and 31.10 mg/g. The fitting results of kinetics prove that the adsorption process of La(III) and Y(III) follows the pseudosecond-order model. Thus, natural orange peel as a recyclable biosorbent has potential economic and applicative benefits to remove La(III) and Y(III) from aqueous solutions.
{"title":"Adsorption Performance of La(III) and Y(III) on Orange Peel: Impact of Experimental Variables, Isotherms, and Kinetics","authors":"Li Liu, Y. Rao, Changshun Tian, Tao Huang, Jiacheng Lu, Mei-dao Zhang, Min Han","doi":"10.1155/2021/7189639","DOIUrl":"https://doi.org/10.1155/2021/7189639","url":null,"abstract":"To alleviate the environmental problem associated with rare earth wastewater, this research applied waste orange peel (OP) for the adsorption of La(III) and Y(III) from aqueous solution. The adsorption properties of orange peel are characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), and the participation of hydroxyl and other oxygen-containing groups that promote the physical-chemical interaction is verified. Batch adsorption results suggest that orange peel possesses a satisfactory adsorption performance for La(III) and Y(III). The optimal adsorption conditions were obtained at pH of 6, temperature of 40°C, appropriate dosage of 2 g/L and 3 g/L, contact time of 30 min, and initial ion concentration of 32 mg/L. Under the same condition, adsorption performance of La(III) is better than that of Y(III). The experimental data is well fitted by the Langmuir isotherm model with \u0000 \u0000 correlation\u0000 \u0000 coefficient\u0000 \u0000 \u0000 \u0000 \u0000 \u0000 R\u0000 \u0000 \u0000 2\u0000 \u0000 \u0000 \u0000 \u0000 >\u0000 0.9\u0000 \u0000 and the minimum standard error values. Equilibrium results show that Langmuir monolayer adsorption capacity of La(III) and Y(III) onto orange peel is up to 37.61 and 31.10 mg/g. The fitting results of kinetics prove that the adsorption process of La(III) and Y(III) follows the pseudosecond-order model. Thus, natural orange peel as a recyclable biosorbent has potential economic and applicative benefits to remove La(III) and Y(III) from aqueous solutions.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45532993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Alosaimi, I. Alsohaimi, T. Dahan, Qiao Chen, Ayman A. O. Younes, B. El-Gammal, S. Melhi
Concerns have been increased regarding the existence of pollutants in environmental water resources and their risks to the ecosystem and human society. TiO2 photocatalyst is considered as an effective photocatalyst to remove the pollutants. Herein, the mesoporous TiO2-SBA-15 was prepared using the rice husk extract as the silica source. The fabricated nanocomposites were characterized using FTIR, small and wide angle XRD, Raman spectroscopy, UV-vis, BET surface area analysis, and HRTEM. The photocatalytic efficiency of the composites for the degradation of methylene blue (MB) has been evaluated under UV irradiation. Interestingly, due to the excellent dispersion of TiO2 on the wall of SBA-15 and good hydrophilicity, the nanocomposites displayed a good catalytic activity. The higher photodegradation performance was achieved by the composite containing 10 wt% TiO2 by which the MB was fully degraded within 15-20 min of irradiation. Besides, TiO2-SBA-15 could effectively inhibit the growth of Gram-positive and Gram-negative bacteria. These results offer a practical and economic approach in the environmental management industries.
{"title":"Photocatalytic Degradation of Methylene Blue and Antibacterial Activity of Mesoporous TiO2-SBA-15 Nanocomposite Based on Rice Husk","authors":"E. Alosaimi, I. Alsohaimi, T. Dahan, Qiao Chen, Ayman A. O. Younes, B. El-Gammal, S. Melhi","doi":"10.1155/2021/9290644","DOIUrl":"https://doi.org/10.1155/2021/9290644","url":null,"abstract":"Concerns have been increased regarding the existence of pollutants in environmental water resources and their risks to the ecosystem and human society. TiO2 photocatalyst is considered as an effective photocatalyst to remove the pollutants. Herein, the mesoporous TiO2-SBA-15 was prepared using the rice husk extract as the silica source. The fabricated nanocomposites were characterized using FTIR, small and wide angle XRD, Raman spectroscopy, UV-vis, BET surface area analysis, and HRTEM. The photocatalytic efficiency of the composites for the degradation of methylene blue (MB) has been evaluated under UV irradiation. Interestingly, due to the excellent dispersion of TiO2 on the wall of SBA-15 and good hydrophilicity, the nanocomposites displayed a good catalytic activity. The higher photodegradation performance was achieved by the composite containing 10 wt% TiO2 by which the MB was fully degraded within 15-20 min of irradiation. Besides, TiO2-SBA-15 could effectively inhibit the growth of Gram-positive and Gram-negative bacteria. These results offer a practical and economic approach in the environmental management industries.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41460957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With the intensification of human activities, arsenite (As(III)) pollutant from the soil and ground water has been a threat to human health, and the problem gradually becomes the focus of attention. In this study, the effects of several environment factors on As(III) removal ability of complex minerals are determined through the analysis of mineralogical characteristics of the complex synthesis of hematite and kaolin, using X-ray diffraction, Fourier transform infrared, and specific surface area. In the results, the XRD patterns of hematite and kaolin complexes indicate that the loading covers up some characteristic peaks of minerals in kaolin, which can be that hematite loading decrease the order of structure for some minerals. With increasing Fe content, the hydroxyl sites gradually increase, therefore strengthening the As(III) removal ability of complexes. With increasing the As(III) concentration, the removal ratios of kaolin on As(III) almost keep unchanged and that of complexes show no obvious regularity. However, with the pH increasing, the removal ratios of all samples keep increasing. Furthermore, the increasing of As(III) concentration and pH both improve As(III) removal amount significantly, especially for As(III) concentration. In addition, there is no forming of new mineral through it as observed by XRD. Therefore, hematite loading can promote the As(III) removal on kaolin through adsorption in different environments, which can provide a better method for the remediation of arsenic pollution.
{"title":"The Effect of Proton and Arsenic Concentration on As(III) Removal by Hematite and Kaolin Complexes","authors":"Shuai Lan, Siyu Zhou, Qin Zhang, Yang Li, Yupeng Yan, Feng Liang, Guanjie Jiang, Zhangjie Qin","doi":"10.1155/2021/3126767","DOIUrl":"https://doi.org/10.1155/2021/3126767","url":null,"abstract":"With the intensification of human activities, arsenite (As(III)) pollutant from the soil and ground water has been a threat to human health, and the problem gradually becomes the focus of attention. In this study, the effects of several environment factors on As(III) removal ability of complex minerals are determined through the analysis of mineralogical characteristics of the complex synthesis of hematite and kaolin, using X-ray diffraction, Fourier transform infrared, and specific surface area. In the results, the XRD patterns of hematite and kaolin complexes indicate that the loading covers up some characteristic peaks of minerals in kaolin, which can be that hematite loading decrease the order of structure for some minerals. With increasing Fe content, the hydroxyl sites gradually increase, therefore strengthening the As(III) removal ability of complexes. With increasing the As(III) concentration, the removal ratios of kaolin on As(III) almost keep unchanged and that of complexes show no obvious regularity. However, with the pH increasing, the removal ratios of all samples keep increasing. Furthermore, the increasing of As(III) concentration and pH both improve As(III) removal amount significantly, especially for As(III) concentration. In addition, there is no forming of new mineral through it as observed by XRD. Therefore, hematite loading can promote the As(III) removal on kaolin through adsorption in different environments, which can provide a better method for the remediation of arsenic pollution.","PeriodicalId":7315,"journal":{"name":"Adsorption Science & Technology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2021-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48217322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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