scholarly journals Preparation and characterization of a high strength self-repairing galactomannan hydrogel

BioResources ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 9853-9866
Author(s):  
Jiufang Duan ◽  
Yuxue Gao ◽  
Yirong Huang ◽  
Lin Li ◽  
Jianxin Jiang
Keyword(s):  
Methylene Blue ◽  
Water Absorption ◽  
Removal Rate ◽  
High Strength ◽  
Maximum Adsorption Capacity ◽  
Self Healing ◽  
Healing Efficiency ◽  
Maximum Water ◽  
Water Absorption Property

Autonomous self-repairing properties can prolong the service life of materials. In this paper, galactomannan hydrogel with high mechanical strength was prepared by graft copolymerization of galactomannan with acrylamide and octadecyl methacrylate in aqueous solution. The microstructure, water absorption property, self-healing behavior, and mechanical properties of the hydrogels were investigated using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM), etc. The galactomannan hydrogel had the highest tensile strength of 49 KPa and strain of 3000%. The water absorption reached 2340%, and the removal rate of methylene blue was more than 80%. Galactomannan hydrogels demonstrated significant self-healing properties. The cut hydrogel was quite effective in self-repairing in a few minutes, and the self-repairing strength increased with increasing contact time of hydrogel cut surfaces. The healing efficiency of fracture strain could reach 92.7% of the original sample in 10 h. The maximum water absorption of hydrogel reached 2340%. The maximum removal rate of methylene blue by hydrogel reached 80.5%, and the maximum adsorption capacity was 19.3 mg/g. The novelty of the work lies in octadecyl methacrylate being used for galactomannan cross-linking with the ability to self-repair after fracture. The galactomannan self-healing hydrogel has potential in water treatment and sealing technology.

scholarly journals Synthesis and characterization of Cu(OH)2-NWs-PVA-AC Nano-composite and its use as an efficient adsorbent for removal of methylene blue

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sivarama Krishna Lakkaboyana ◽  
Khantong Soontarapa ◽  
Nabel Kalel Asmel ◽  
Vinay Kumar ◽  
Ravi Kumar Marella ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Kinetic Models ◽  
Batch Reactor ◽  
Maximum Adsorption Capacity ◽  
Nano Composite ◽  
Adsorption Processes ◽  
Intra Particle Diffusion ◽  
Short Time ◽  
Efficient Adsorbent

AbstractThe present study focused on the synthesis of copper hydroxide nanowires decorated on activated carbon (Cu(OH)2-NWs-PVA-AC). The obtained Cu(OH)2-NWs-PVA-AC Nano-composite was distinguished by XRD, SEM, EDX, BET, FTIR and XPS respectively. Besides, different variables such as solution pH, and initial dye concentration, contact time, and temperature were performed on the adsorption efficiency of MB in a small batch reactor. Further, the experimental results are analyzed by various kinetic models via PFO, PSO, intra-particle diffusion and Elovich models, and the results revealed that among the kinetic models, PSO shows more suitability. In addition, different adsorption isotherms were applied to the obtained experimental data and found that Langmuir–Freundlich and Langmuir isotherm were best fits with the maximum adsorption capacity of 139.9 and 107.6 mg/g, respectively. The Nano-composite has outstanding MB removal efficiency of 94–98.5% with a span of 10 min. and decent adsorption of about 98.5% at a pH of 10. Thermodynamic constants like Gibbs free energy, entropy, and enthalpy were analyzed from the temperature reliance. The results reveal the adsorption processes are spontaneous and exothermic in nature. The high negative value of ΔG° (− 44.11 to − 48.86 kJ/mol) and a low negative value of ΔH° (− 28.96 kJ/mol) show the feasibility and exothermic nature of the adsorption process. The synthesized dye was found to be an efficient adsorbent for the potential removal of cationic dye (methylene blue) from wastewater within a short time.

Preparation and characterization of double network hydrogel with high-strength and self-healing

2021 ◽  
pp. 102450
Author(s):  
Shubin Li ◽  
Xiao Wang ◽  
Jiang Zhu ◽  
Zhenyu Wang ◽  
Lu Wang
Keyword(s):  
High Strength ◽  
Self Healing ◽  
Double Network

A room-temperature self-healing elastomer with ultra-high strength and toughness fabricated via optimized hierarchical hydrogen-bonding interactions

2022 ◽  
Author(s):  
Liangliang Xia ◽  
Ming Zhou ◽  
Hongjun Tu ◽  
wen Zeng ◽  
xiaoling Yang ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Mechanical Strength ◽  
Room Temperature ◽  
Polymeric Materials ◽  
High Strength ◽  
Self Healing ◽  
High Mechanical Strength ◽  
Hydrogen Bonding Interactions ◽  
Healing Efficiency ◽  
Good Healing

The preparation of room-temperature self-healing polymeric materials with good healing efficiency and high mechanical strength is challenging. Two processes are essential to realise the room-temperature self-healing of materials: (a) a...

scholarly journals Synthesis and characterization of modified activated carbon (MgO/AC) for methylene blue adsorption: optimization, equilibrium isotherm and kinetic studies

2021 ◽  
Author(s):  
Vahab Ghalehkhondabi ◽  
Alireza Fazlali ◽  
Keyhan Ketabi
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Natural Waters ◽  
Sol Gel ◽  
Kinetic Studies ◽  
Maximum Adsorption Capacity ◽  
Human Beings ◽  
Operational Conditions ◽  
Coating Method

Abstract Methylene blue (MB) is the cationic dye that is widely used for coloring cotton, wool, and silk. Since MB is harmful to human beings and toxic to microorganisms, there is the need to find cheap and efficient methods for removal of MB from wastewater prior to disposal into natural waters. In the present study, MB adsorption potential of MgO/AC prepared using a sol–gel-thermal deep-coating method was compared with the activated carbon (AC). The central composite design (CCD) as a method of the response surface methodology (RSM) was applied to minimize the number of runs and process optimization. The characterization of the microporous MgO/AC composite showed that the magnesium oxide nanoparticles were successfully coated on the AC and the BET specific surface area of AC and MgO/AC were 1,540 and 1,246 m2/g, respectively. The MB removal efficiency and the maximum adsorption capacity of AC and MgO/AC were 89.6, 97.5% and 571.7, 642.3 mg/g, respectively under optimum operational conditions of initial dye concentration of 100.9 mg/L, the adsorbent dosage of 69.4 mg/100 mL, pH of 10.2 and contact time of 149.1 min. According to an analysis of variance (ANOVA), the initial dye concentration and its interaction with the other effective factors have a large impact on adsorption efficiency. Furthermore, the mechanism of adsorption followed the Langmuir isotherm (R2 = 0.9935, Δqe = 2.9%) and adsorption kinetics fitted by the pseudo-second-order model (R2 = 0.9967, Δqe = 6.6%). Finally, our results suggest that the prepared MgO/AC is an efficient and promising material for dye wastewater treatment.

Characterization of the Corallina Elongata Alga and Study of its Biosorption Properties for Methylene Blue

2019 ◽  
Vol 41 (1) ◽  
pp. 62-62
Author(s):  
Farida Bouremmad Farida Bouremmad ◽  
Abdennour Bouchair Abdennour Bouchair ◽  
Sorour Semsari Parapari Sorour Semsari Parapari ◽  
Shalima Shawuti and Mehmet Ali Gulgun Shalima Shawuti and Mehmet Ali Gulgun
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Adsorption Capacity ◽  
Low Cost ◽  
Mediterranean Coast ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Aquatic Biomass ◽  
Equilibrium Data

Biosorbents can be an alternative to activated carbon. They are derived from agricultural by-products or aquatic biomass. They are low cost and they may have comparable performances to those of activated carbon. The present study focuses on the characterization of the Corallina Elongata (CE) alga and its adsorption performance for Methylene Blue (MB), this alga is found in abundance at the Mediterranean coast of the city of Jijel in eastern Algeria. The dried alga was characterized using various characterization techniques such as DTA, TG, FTIR, XRD, SEM and EDX, which showed that the material consists essentially of a calcite containing magnesium. Batch adsorption studies were carried out and the effect of experimental parameters Such as pH, initial dye concentration, temperature, adsorbent dose and contact time, on the adsorption of MB was studied. The kinetic experimental data were found to conform to the pseudo-second-order model with good correlation and equilibrium data were best fitted to The Langmuir model, with a maximum adsorption capacity of 34.4 mg/g. The adsorption isotherms at various temperatures allowed the determination of certain thermodynamic parameters (ΔG, ΔH and ΔS). Finally, the adsorption results showed a good affinity between CE and MB with a high adsorption capacity.

scholarly journals Preparation and Characterization of Chabazite from Construction Waste and Application as an Adsorbent for Methylene Blue

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Xue Song ◽  
Yingming Zhang ◽  
Xiangke Cui ◽  
Fangfang Liu ◽  
Hailiang Zhao
Keyword(s):  
Methylene Blue ◽  
Removal Rate ◽  
Synthesis Method ◽  
Chemical Properties ◽  
Maximum Adsorption Capacity ◽  
Building Projects ◽  
Construction Waste ◽  
Alkali Fusion ◽  
Adsorption Desorption ◽  
Physical And Chemical

Construction waste, produced from building projects, was utilized to prepare chabazite by alkali fusion hydrothermal synthesis method. The synthesized chabazite was used as an adsorbent for the removal of methylene blue (MB). XRD, FTIR, and N2 adsorption/desorption curves were adopted to describe the physical and chemical properties of the samples. The results show that the synthesized chabazite possesses crystalline structure, typical functional groups, and large specific surface area of 421.34 m2 g-1. Adsorption isotherms and kinetic curves show that the adsorption process follows the Langmuir model and pseudo-second-order kinetics model. The maximum adsorption capacity of MB on the synthesized chabazite reaches up to 129.18 mg g-1 at 298 K, which is about 16 times that of construction waste. The removal rate of MB reaches more than 90%, and the adsorbed amount is about 35 mg g-1 after 1 h at 298 K. Thermodynamic parameters, namely Δ H , Δ S , and Δ G of -12.83 kJ mol-1, -27.37 J mol-1 K-1, and -4.68 kJ mol-1 at 298 K, respectively, indicate that the adsorption of MB on the chabazite is physical, orderliness-tended, and spontaneous process. Moreover, the synthesized chabazite has a good property of regeneration and reuse. The results indicate that using construction waste to prepare chabazite in application as an adsorbent is feasible, which provides a novel and environment-friendly way for recycling construction waste.

scholarly journals Evaluation of Kalalani vermiculite for production of high strength porcelain insulators

2019 ◽  
Vol 51 (2) ◽  
pp. 223-232 ◽  
Author(s):  
Blasius Ngayakamo ◽  
Eugene Park
Keyword(s):  
Water Absorption ◽  
Bulk Density ◽  
Bending Strength ◽  
Raw Materials ◽  
High Strength ◽  
Microstructural Characterization ◽  
Dielectric Strength ◽  
Raw Material ◽  
Porcelain Insulators

The present work has evaluated Kalalani vermiculite as a potential raw material for the production of high strength porcelain insulators. Three porcelain compositions were prepared to contain 0, 20 and 30 wt% of Kalalani vermiculite. Porcelain samples were fabricated using a semi-drying method. The chemical, mineralogical phases and microstructural characterization of the raw materials were carried out using XRF, XRD, and SEM techniques, respectively. Water absorption, bulk density, dielectric and bending strengths were performed on porcelain samples fired up to 1300?C. However, at the sintering temperature of 1250?C, the porcelain sample with 20 wt% of Kalalani vermiculite gave the dielectric strength of 61.3 kV/mm, bending strength of 30.54 MPa, bulk density of 2.21 g/cm3 and low water absorption value of 0.21 % which is the prerequisite properties for high strength porcelain insulators. It was therefore concluded that Kalalani vermiculite has the potential to be used for the production of high strength porcelain insulators

scholarly journals Preparation and characterization of multifunctional sponge-gourd fibers (Luffa cylindrica)/ hydroxyapatite composites for removal of lead and methylene blue

2021 ◽  
Author(s):  
Ahmed A. Oun ◽  
Kholod H. Kamal ◽  
Khaled Farroh ◽  
Esmat F. Ali ◽  
Mohamed A. Hassan
Keyword(s):  
Methylene Blue ◽  
High Efficiency ◽  
Average Length ◽  
Maximum Adsorption Capacity ◽  
Luffa Cylindrica ◽  
Sponge Gourd ◽  
Type Contact ◽  
Pseudo Second Order ◽  
Short Time

Abstract Cellulose, oxidized-fibers, and oxidized-nanocellulose were isolated from sponge-gourd fibers (Luffa cylindrica). Isolated materials showed different morphology (shape and size), chemical, crystalline properties, and removal efficiency against methylene blue (MB) and lead ions (Pb2+). The cellulosic materials showed high efficiency in removing MB more than Pb2+. So, different luffa forms/hydroxyapatite (HAp) composites were prepared and used as adsorbents for removal of both MB and Pb2+ from aqueous solutions. The effect of sorbent type, contact time, and initial MB and Pb2+ concentrations were studied. HAp was successfully synthesized on the surface of luffa with an average length of 40–56 nm and width of 14–19 nm. Kinetic and adsorption studies of MB and Pb2+ ions were well fitted with the pseudo-second-order model and Langmuir model. The maximum adsorption capacity of MB was 25.2 mg/g, 30.8 mg/g, and 36.2 mg/g for oxidized-fibers/HAp, oxidized-fibers, and cellulose, respectively, and for Pb2+ was 625 mg/g, 714 mg/g, and 714.5 mg/g for oxidized-fibers/HAp, oxidized-nanocellulose/HAp, and cellulose/HAp, respectively. Also, more than 85% of MB (25 mg/L) and 95% of lead (500 mg/L) were removed within the first 5 min. Oxidize-fibers/HAp composite showed effective adsorption with both MB and Pb2+ in a very short time.

Characterization of Ceramic Composite Waste of Granite, Marble and Caulim for Production of Coating Plates

2014 ◽  
Vol 798-799 ◽  
pp. 300-305
Author(s):  
Joseanne Lima Sales ◽  
C.R.S. Morais ◽  
L.M.R. Lima ◽  
J.L. Araújo ◽  
J.C.B. Cibalde
Keyword(s):  
Water Absorption ◽  
Mining Industry ◽  
Ceramic Matrix Composites ◽  
High Strength ◽  
Strength Properties ◽  
Matrix Composites ◽  
Polymer Resin ◽  
Dry Grinding ◽  
Testing Technology

The mining industry generates large amounts of waste resulting in a very strong environmental impact. Its reuse in ceramic matrix composites are used as coating for floors that have high strength properties with low porosity due to the addition of a structuring polyester resin . This perspective, this work aims at the use of waste generated in the exploration and kaolin processing industries , and solid waste from the cutting of ornamental marble and granite , studying their properties in anticipation of production of coating plates . The residues were benefited by using the process of dry grinding in mill gauges and passed through sieve 0.074 mm ( No. 200 ABNT ) . Were performed on composites testing technology ( water absorption , apparent porosity , bulk density and flexural strength ) and microstructural ( Scanning Electron Microscopy - SEM) . The results showed that the composites showed water absorption ≤ 0.5 having no direct relationship with the porosity , which showed strength within the required standards ( ABNT 13,816 ) for coating plates . Variations in composition ( resin / residue ) showed that composites with higher strength and increased amount of waste resin showed less porous structure , a fact which can be attributed to a better adherence of these residues to the polymer resin and a process of mixing the components more efficient , showing the viability of its production having demonstrated satisfactory properties.

Sign in / Sign up

Export Citation Format

Share Document