Characterizing Bacterial Cellulose Produced byKomagataeibacter sucrofermentans H-110 on Molasses Medium and Obtaining a Biocomposite Based on It for the Adsorption of Fluoride

Currently, there is an increased demand for biodegradable materials in society due to growing environmental problems. Special attention is paid to bacterial cellulose, which, due to its unique properties, has great prospects for obtaining functional materials for a wide range of applications, including adsorbents. In this regard, the aim of this study was to obtain a biocomposite material with adsorption properties in relation to fluoride ions based on bacterial cellulose using a highly productive strain of Komagataeibacter sucrofermentans H-110 on molasses medium. Films of bacterial cellulose were obtained. Their structure and properties were investigated by FTIR spectroscopy, NMR, atomic force microscopy, scanning electron microscopy, and X-ray structural analysis. The results show that the fiber thickness of the bacterial cellulose formed by the K. sucrofermentans H-110 strain on molasses medium was 60–90 nm. The degree of crystallinity of bacterial cellulose formed on the medium was higher than on standard Hestrin and Schramm medium and amounted to 83.02%. A new biocomposite material was obtained based on bacterial cellulose chemically immobilized on its surface using atomic-layer deposition of nanosized aluminum oxide films. The composite material has high sorption ability to remove fluoride ions from an aqueous medium. The maximum adsorption capacity of the composite is 80.1 mg/g (F/composite). The obtained composite material has the highest adsorption capacity of fluoride from water in comparison with other sorbents. The results prove the potential of bacterial cellulose-based biocomposites as highly effective sorbents for fluoride.

Download Full-text

Sequential Oxidation on Wood and Its Application in Pb2+ Removal from Contaminated Water

Polysaccharides ◽

10.3390/polysaccharides2020017 ◽

2021 ◽

Vol 2 (2) ◽

pp. 245-256

Author(s):

Priyanka R. Sharma ◽

Sunil K. Sharma ◽

Marc Nolan ◽

Wenqi Li ◽

Lakshta Kundal ◽

...

Keyword(s):

Adsorption Capacity ◽

Average Length ◽

Sodium Chlorite ◽

Contaminated Water ◽

Maximum Adsorption Capacity ◽

Fiber Morphology ◽

Carboxylate Groups ◽

Carboxylate Content ◽

Wide Range ◽

Length Width

Raw wood was subjected to sequential oxidation to produce 2,3,6-tricarboxycellulose (TCC) nanofibers with a high surficial charge of 1.14 mmol/g in the form of carboxylate groups. Three oxidation steps, including nitro-oxidation, periodate, and sodium chlorite oxidation, were successfully applied to generate TCC nanofibers from raw wood. The morphology of extracted TCC nanofibers measured using TEM and AFM indicated the average length, width, and thickness were in the range of 750 ± 110, 4.5 ± 1.8, and 1.23 nm, respectively. Due to high negative surficial charges on TCC, it was studied for its absorption capabilities against Pb2+ ions. The remediation results indicated that a low concentration of TCC nanofibers (0.02 wt%) was able to remove a wide range of Pb2+ ion impurities from 5–250 ppm with an efficiency between 709–99%, whereby the maximum adsorption capacity (Qm) was 1569 mg/g with R2 0.69531 calculated from Langmuir fitting. It was observed that the high adsorption capacity of TCC nanofibers was due to the collective effect of adsorption and precipitation confirmed by the FTIR and SEM/EDS analysis. The high carboxylate content and fiber morphology of TCC has enabled it as an excellent substrate to remove Pb2+ ions impurities.

Download Full-text

Adsorption of hexavalent chromium by polyacrylonitrile-based porous carbon from aqueous solution

Royal Society Open Science ◽

10.1098/rsos.171662 ◽

2018 ◽

Vol 5 (1) ◽

pp. 171662 ◽

Cited By ~ 14

Author(s):

Bin Feng ◽

Wenzhong Shen ◽

Liyi Shi ◽

Shijie Qu

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Porous Carbon ◽

Photoelectron Spectroscopy ◽

Ph Value ◽

Functional Materials ◽

High Specific Surface Area ◽

Maximum Adsorption Capacity ◽

Elementary Analysis ◽

Initial Adsorption

Owing to the unique microporous structure and high specific surface area, porous carbon could act as a good carrier for functional materials. In this paper, polyacrylonitrile (PAN)-based porous carbon materials (PPC-0.6-600, PPC-0.8-600, PPC-0.6-800 and PPC-0.8-800) were prepared by heating KOH at 600°C and 800 o C for the removal of Cr(VI) from aqueous solution. The adsorbent was characterized by the techniques of Fourier transform infrared spectroscopy (FT-IR), elementary analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and N 2 adsorption techniques. The results showed that the adsorption capacity increased with decreasing pH value of the initial solution. The adsorption capacity of Cr(VI) on PPC-0.8-800 was much greater than that on other materials, and maximum adsorption capacity were calculated to be 374.90 mg g −1 . Moreover, PPC-0.8-800 had superior recyclability for the removal of Cr(VI) from wastewater, about 82% of its initial adsorption capacity was retained even after five cycles. The result of kinetic simulation showed that the adsorption of Cr(VI) on the PAN-based porous carbon could be described by pseudo-second-order kinetics. The adsorption process was the ionic interaction between protonated amine groups of PPC and HCrO 4 - ions.

Download Full-text

Synthesis of Calcium Silicate Hydrate Compounds From Wet Flue Gas Desulfurization (FGD) Waste

Journal of Applied Materials and Technology ◽

10.31258/jamt.1.2.88-95 ◽

2020 ◽

Vol 1 (2) ◽

pp. 88-95

Author(s):

Denise Alves Fungaro ◽

Lucas Caetano Grosche ◽

Juliana de Carvalho Izidoro

Keyword(s):

Adsorption Capacity ◽

Flue Gas ◽

Calcium Silicate ◽

Calcium Silicate Hydrate ◽

Flue Gas Desulfurization ◽

Maximum Adsorption Capacity ◽

Fusion Temperature ◽

Hydrothermal Temperature ◽

X Ray ◽

Wide Range

In this study Calcium silicate hydrate based products (CSHP) were synthesized from wet flue gas desulfurization waste (FGD) by alkali fusion followed by hydrothermal treatment. The effect of various factors on the formation of products, such as mineralizing agent, fusion temperature and time, crystallization time and addition of Ca and Si were studied as well as the conditions optimized. The FGD and synthesized materials were characterized by using X-Ray (XRD), Scanning Electron Microscope (SEM), X-ray fluorescence (XFR), among other methods. A fusion temperature of 600 °C with NaOH, fusion duration of 1 h, and a subsequent hydrothermal temperature of 100 °C for a reaction of 24 h were found to be the optimal conditions. In these synthesis conditions, CSHP containing tobermorite and Al-tobermorite was the major phases. The synthesized CSHP revealed high selective uptake for Cs+ in water. The maximum adsorption capacity of Cs+ onto the synthesized material, as calculated from the Langmuir model, was 1949 µmol g-1. The performance on the Cs+ removal in the presence of high Na+ contents was also evaluated. The adsorbent material showed a high Cs+ adsorption capacity in deionized water and a decrease of 56% and 62% in saturated media with the Na+ ions and seawater, respectively. Therefore, CSHP as a higher value-added product can be obtained from a by-product of a coal-fired power plant, which has wide range applications, including for Cs+ removal from wastewater.

Download Full-text

Furanoate-Based Nanocomposites: A Case Study Using Poly(Butylene 2,5-Furanoate) and Poly(Butylene 2,5-Furanoate)-co-(Butylene Diglycolate) and Bacterial Cellulose

Polymers ◽

10.3390/polym10080810 ◽

2018 ◽

Vol 10 (8) ◽

pp. 810 ◽

Cited By ~ 9

Author(s):

Marina Matos ◽

Andreia F. Sousa ◽

Nuno H. C. S. Silva ◽

Carmen S. R. Freire ◽

Márcia Andrade ◽

...

Keyword(s):

Bacterial Cellulose ◽

High Strength ◽

Barrier Properties ◽

Degree Of Crystallinity ◽

Cellulose Fibres ◽

Nano Composite ◽

Elongation At Break ◽

Wide Range ◽

The Degree Of Crystallinity

Polyesters made from 2,5-furandicarboxylic acid (FDCA) have been in the spotlight due to their renewable origins, together with the promising thermal, mechanical, and/or barrier properties. Following the same trend, (nano)composite materials based on FDCA could also generate similar interest, especially because novel materials with enhanced or refined properties could be obtained. This paper presents a case study on the use of furanoate-based polyesters and bacterial cellulose to prepare nanocomposites, namely acetylated bacterial cellulose/poly(butylene 2,5-furandicarboxylate) and acetylated bacterial cellulose/poly(butylene 2,5-furandicarboxylate)-co-(butylene diglycolate)s. The balance between flexibility, prompted by the furanoate-diglycolate polymeric matrix; and the high strength prompted by the bacterial cellulose fibres, enabled the preparation of a wide range of new nanocomposite materials. The new nanocomposites had a glass transition between −25–46 °C and a melting temperature of 61–174 °C; and they were thermally stable up to 239–324 °C. Furthermore, these materials were highly reinforced materials with an enhanced Young’s modulus (up to 1239 MPa) compared to their neat copolyester counterparts. This was associated with both the reinforcing action of the cellulose fibres and the degree of crystallinity of the nanocomposites. In terms of elongation at break, the nanocomposites prepared from copolyesters with higher amounts of diglycolate moieties displayed higher elongations due to the soft nature of these segments.

Download Full-text

Characterization of Acid-Aged Biochar and Its Ammonium Adsorption in an Aqueous Solution

Materials ◽

10.3390/ma13102270 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2270 ◽

Cited By ~ 3

Author(s):

Zhiwen Wang ◽

Jie Li ◽

Guilong Zhang ◽

Yancai Zhi ◽

Dianlin Yang ◽

...

Keyword(s):

Adsorption Capacity ◽

Functional Groups ◽

Chemical Properties ◽

Physical Property ◽

Sorption Process ◽

Peanut Shell ◽

Characteristic Analysis ◽

Sorption Ability ◽

Wide Range ◽

Aging Conditions

According to its characteristics, biochar originating originating from biomass is accepted as a multifunctional carbon material that supports a wide range of applications. With the successfully used in reducing nitrate and adsorbing ammonium, the mechanism of biochar for nitrogen fixation in long-term brought increasing attention. However, there is a lack of analysis of the NH4+-N adsorption capacity of biochar after aging treatments. In this study, four kinds of acid and oxidation treatments were used to simulate biochar aging conditions to determine the adsorption of NH4+-N by biochar under acidic aging conditions. According to the results, acid-aged biochar demonstrated an enhanced maximum NH4+-N adsorption capacity of peanut shell biochar (PBC) from 24.58 to 123.28 mg·g−1 after a H2O2 modification. After the characteristic analysis, the acid aging treatments, unlike normal chemical modification methods, did not significantly change the chemical properties of the biochar, and the functional groups and chemical bonds on the biochar surface were quite similar before and after the acid aging process. The increased NH4+-N sorption ability was mainly related to physical property changes, such as increasing surface area and porosity. During the NH4+ sorption process, the N-containing functional groups on the biochar surface changed from pyrrolic nitrogen to pyridinic nitrogen, which showed that the adsorption on the surface of the aged biochar was mainly chemical adsorption due to the combination of π-π bonds in the sp2 hybrid orbital and a hydrogen bonding effect. Therefore, this research establishes a theoretical basis for the agricultural use of aged biochar.

Download Full-text

Synthesis of a Novel Ce-bpdc for the Effective Removal of Fluoride from Aqueous Solution

Advances in Condensed Matter Physics ◽

10.1155/2017/8305765 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Changqing Zhao ◽

Yanwei Cui ◽

Fang Fang ◽

Si Ok Ryu ◽

Jiarui Huang

Keyword(s):

Adsorption Capacity ◽

Removal Efficiency ◽

Photoelectron Spectroscopy ◽

Ph Value ◽

Binding Capacity ◽

Fluoride Removal ◽

Maximum Adsorption Capacity ◽

Fluoride Ions ◽

X Ray ◽

Fluoride Adsorption

Ce-1,1′-biphenyl-4,4′-dicarboxylic acid (Ce-bpdc), a novel type of metal organic framework, was synthesized and applied to remove excessive fluoride from water. The structure and morphology of Ce-bpdc were measured by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The effects, such as saturated adsorption capacity, HCO3-, and pH, were investigated. The optimal pH value for fluoride adsorption was the range from 5 to 6. The coexisting bicarbonate anions have a little influence on fluoride removal. The fluoride adsorption over the Ce-bpdc adsorbent could reach its equilibrium in about 20 min. The Ce-bpdc coordination complex exhibited high binding capacity for fluoride ions. The maximum adsorption capacity calculated from Langmuir model was high up to 45.5 mg/g at 298 K (pH = 7.0) and the removal efficiency was greater than 80%. In order to investigate the mechanism of fluoride removal, various adsorption isotherms such as Langmuir and Freundlich were fitted. The experimental data revealed that the Langmuir isotherm gave a more satisfactory fit for fluoride removal. Finally, the tested results of ground water samples from three places, Yuefang, Jiangji, and Sanyi which exhibited high removal efficiency, also demonstrate the potential utility of the Ce-bpdc as an effective adsorbent.

Download Full-text

Analysis of the physicochemical and sorption characteristics of composites based on zeolite and chamotte clay

MATEC Web of Conferences ◽

10.1051/matecconf/202134001027 ◽

2021 ◽

Vol 340 ◽

pp. 01027

Author(s):

Zarina Baranchiyeva ◽

Gulziya Seilkhanova ◽

Akmaral Rakhym

Keyword(s):

Composite Material ◽

Specific Surface ◽

Adsorption Capacity ◽

Structural Characteristics ◽

Quantitative Composition ◽

Maximum Adsorption Capacity ◽

Sorption Activity ◽

Qualitative And Quantitative ◽

Active Centres ◽

Sorption Characteristics

Clays and aluminosilicate materials are known as effective sorbents for purification of wastewater from various types of contaminants. Some properties and sorption activity of materials based on the zeolite of Shankanai deposit and Chamotte clay towards Cd2+ ions were analyzed in the present work. The structural characteristics of the studied objects, their qualitative and quantitative composition were determined by the SEM and EDAX methods. It was found that maximum adsorption capacity (qe) of the initial zeolite for extraction Cd2+ ions is (7.3±0.11) mg/g, while for Chamotte clay this value equals to (5.3±0.12) mg/g. After modification with polyvinylpyrrolidone, qe increased to (10.1±0.08) mg/g for zeolite, and (8.5±0.15) mg/g for Chamotte clay. Developed specific surface of the composite material (sorbent) and complexation with the active centres of thepolymer couldbe a resultof Cd2+ ions binding.

Download Full-text

Adsorption Studies on the Removal of an Herbicide (Atrazine) Using Activated Carbons Prepared from Agricultural Waste Sugarcane Bagasse

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.251.378 ◽

2012 ◽

Vol 251 ◽

pp. 378-382 ◽

Cited By ~ 2

Author(s):

Ken Lin Chang ◽

Yi Hsuan Shih ◽

Chao Heng Tseng ◽

Shui Tein Chen ◽

Chih Cheng Chen

Keyword(s):

Adsorption Capacity ◽

Sugarcane Bagasse ◽

Activated Carbons ◽

Ph Value ◽

Agricultural Waste ◽

High Surface ◽

High Surface Area ◽

Maximum Adsorption Capacity ◽

Atrazine Concentration ◽

Wide Range

A potassium hydroxide activation method is used to derive activated carbon (AC), which has high surface area of 1,324.62 m2/g, from agricultural waste, i.e. sugarcane bagasse. The adsorption capacity of AC for Atrazine, a widely used herbicide, in aqueous solution is evaluated at different initial Atrazine concentration, temperature, and pH. The results show the maximum adsorption capacity of Atrazine is proportional to the initial concentration of Atrazine. The amount of adsorption is inversely proportional to the temperature, although there is not significant decrease of adsorption capacity when temperature rises. Furthermore, the pH value has no influence on the adsorption of Atrazine, which shows the AC made of sugarcane bagasse has great performance in adsorption over a wide range of pH values.

Download Full-text

A parallel optimisation of adsorption and regeneration properties of activated biochars for wastewater treatment

10.5194/egusphere-egu2020-858 ◽

2020 ◽

Author(s):

Christian Wurzer ◽

Pierre Oesterle ◽

Stina Jansson ◽

Ondrej Masek

Keyword(s):

Wastewater Treatment ◽

Activated Carbon ◽

Adsorption Capacity ◽

Wastewater Treatment Plants ◽

Functional Materials ◽

Additional Treatment ◽

Treatment Temperature ◽

Research Centre ◽

Maximum Adsorption Capacity ◽

Hydrothermal Conditions

The emergence of micropollutants, such as pharmaceuticals in wastewater, presents a potential risk for human health as well as the aquatic environment. Current wastewater treatment plants are generally not capable of removing these pollutants without additional treatment steps. Adsorption on activated carbon is an effective way to remove these contaminants, however, the use of non-renewable feedstocks as well as low regeneration efficiencies increase the environmental costs of this method1. Biochar as a renewable carbon platform material can be specifically designed to overcome these drawbacks2.This study is aimed at designing activated mineral biochar composites with enhanced adsorption capacity for pharmaceuticals while simultaneously optimising their regeneration performance. Two standard biochars from the UK Biochar Research Centre produced at 550&#176;C from softwood and wheat straw were activated in CO2 at 800&#176;C. Additionally, activated mineral biochar composites were produced by the addition of ochre &#8211; a Fe-rich mining waste &#8211; prior to pyrolysis and activation.The activated biochars and activated mineral biochar composites were analysed for their maximum adsorption capacity for two micropollutants - caffeine and fluconazole - and compared to a commercial activated carbon as a reference material. While the activated carbon outperformed all biochar samples, the addition of ochre increased the performance of the activated biochar samples. The regeneration performance was tested in a subsequent experiment. The materials were first loaded with a mix of 10 pharmaceuticals covering antibiotics, fungicides and antidepressants. The loaded biochars were then subjected to a novel regeneration method directly utilising wet adsorbents in contrast to common methods requiring prior drying. Similar to a powerful pressure cooker, solvolytic conversion conditions of water at temperatures ranging from 160 to 320&#176;C and elevated pressures of 15 to 120 bar were used to regenerate the biochars. Hydrothermal treatment at 320&#176;C was found to successfully degrade the adsorbed micropollutants across all biochars. The mineral biochar composites showed increased pollutant degradation most likely due to the catalytic effects of Fe in hydrothermal conditions, lowering the necessary treatment temperature to 280&#176;C.The results show that while designing biochar for certain applications, a simultaneous focus on both the application as well as the regeneration of the material can give a more comprehensive picture of the overall requirements for further optimisation of biochar adsorbents.&#160;<ol><li>Thompson, K. A. et al. Environmental Comparison of Biochar and Activated Carbon for Tertiary Wastewater Treatment. Environ. Sci. Technol. (2016). doi:10.1021/acs.est.6b03239</li> <li>Liu, W. J., Jiang, H. & Yu, H. Q. Development of Biochar-Based Functional Materials: Toward a Sustainable Platform Carbon Material. Chem. Rev. 115, 12251&#8211;12285 (2015).</li> </ol>

Download Full-text

Activated Carbon Loaded Ti3+ Self-Doped TiO2 Composite Material Was Prepared By Microwave Method and Degradation of Rhodamine B Under UV-Light

10.21203/rs.3.rs-704961/v1 ◽

2021 ◽

Author(s):

Yingjie Xu ◽

Qi Zhang ◽

Guiyu Jiang ◽

Hongying Xia ◽

Wuchen Cai ◽

...

Keyword(s):

Composite Material ◽

Adsorption Capacity ◽

Uv Light ◽

Removal Rate ◽

Crystal Form ◽

Band Gap Energy ◽

Maximum Adsorption Capacity ◽

Microwave Method ◽

Preparation Methods ◽

Characterization Methods

Abstract In this work, the AC loaded Ti3+ self-doped TiO2 composite material was synthesized by the microwave method. Through XRD, XPS, SEM, RT-IR, UV-vis and other characterization methods to analyze the crystallinity, valence, morphology and other properties of the composite material. There is a synergistic effect between AC and TiO2, C—O—Ti and O—Ti—C bonds are formed between them. And promote the formation of anatase, make TiO2 form a mixed crystal form, and improve the efficiency of electron-hole separation. The doping of Ti3+ produces the Jahn-Teller effect, which reduces the band gap energy of the composite material to 2.2~2.4eV. The adsorption-catalysis experiment showed that the TiO2/Ti3+/AC composite prepared under microwave conditions has a removal rate of more than 96% for Rh-B, and the removal rate of pure TiO2/Ti3+ is only 50.44%. In addition, the effects of different preparation methods on the removal rate of Rh-B were compared. And it was found that the maximum removal rate of composite materials prepared under conventional conditions was 90.58%, which was significantly lower than the efficiency under microwave conditions. At the same time, the change in the adsorption capacity of AC was explored, and it was found that the saturated adsorption capacity of the 283K composite material was 161.67mg/g. When the temperature was 323K, the maximum adsorption capacity was 250.93mg/g, and the pure AC was only 115.47mg/g. Therefore, the composite material prepared by the microwave method can be regarded as an efficient and economical material for wastewater treatment.

Download Full-text