Adsorption of Congo Red from Aqueous Solution Using La/MFA Composite as Adsorbent

A novel lanthanum/modified fly ash (La/MFA) composite adsorbent prepared by simple solution reaction was used for the adsorption of Congo Red (CR) dye from aqueous solution. The morphology and particle size distribution of the composite were characterized, and the equilibrium adsorption was researched. The results show that the adsorption of CR onto La/MFA can reach equilibrium in 30 minutes. The entire adsorption process can be well described by pseudo-second-order kinetic equation at different temperatures. The value of apparent adsorption activation energy is 16.2kJ/mol. The isothermal data conform to the Langmuir model with the maximum adsorption capacity of 714 mg/g at 298K. According to the negative values of Gibbs free energy change (ΔG°) and enthalpy change (ΔH°), and reduction of Langmuir adsorption coefficient with the increase of temperature, the adsorption system from 298K to 328K is confirmed to be of spontaneous and exothermic nature. The results of SEM and particle size analysis indicate that the particle sizes and specific surface of La/MFA are smaller and coarser than those of FA. As a low-value composite adsorbent, La/MFA is especially effective for the removal of high concentration CR.

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Preparation of Chitosan/Hyperbranched Polyester/Cobalt Composite For Acid Blue 277 Dye Adsorption

Biointerface Research in Applied Chemistry ◽

10.33263/briac114.1165311665 ◽

2020 ◽

Vol 11 (4) ◽

pp. 11653-11665

Keyword(s):

Particle Size ◽

Dye Adsorption ◽

Particle Size Analysis ◽

Isotherm Models ◽

Size Analysis ◽

Order Kinetic ◽

Hyperbranched Polyester ◽

Acid Dye ◽

Equilibrium Studies ◽

Acid Blue

Acid dye effluents are among the popular threatening sources to the environment and human health due to their photochemical stability, complexity, and poor biodegradability. Therefore, this study aims to prepare chitosan/hyperbranched polyester (HBPE)/cobalt composite with ratio (1:1:0.5 wt %, respectively) using emulsion technique as an adsorbent to deal with the acid dye effluent. Chemical structure, morphology, particle size analysis, and thermal stability of the prepared composite were carried out using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM),) dynamic light scattering technique (DLS) and thermogravimetric analysis (TGA). Adsorption isotherms of acid blue 277 dye (AB277), using the different isotherm models (Langmuir, Freundlich, D-R, and Temkin) under removal conditions at pH 3.0 and contact time of 1 h in 10 mL aqueous medium at 25ᴼC, were investigated. The results illustrated that the chitosan/HBPE/Co composite was successfully prepared with a particle size of around 679±494 nm relative to chitosan/HBPE (139±67.6 nm). Also, the pseudo-second-order kinetic model fitted better than the pseudo-first-order one for adsorption of AB277. Batch equilibrium studies showed that chitosan/HBPE/Co composite could be employed as an efficient adsorbent of AB277 dye with an adsorption capacity of 26.74 mg/g, relative to that of chitosan/HBPE (3.19 mg/g).

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Stabilization of Leachate Effected Laterite Soil using Bio-Enzyme(Terrazyme)

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.e6653.018520 ◽

2020 ◽

Vol 8 (5) ◽

pp. 4195-4203

Keyword(s):

Particle Size ◽

Soil Compaction ◽

Ph Value ◽

Particle Size Analysis ◽

California Bearing Ratio ◽

Size Analysis ◽

High Concentration ◽

Effective Technique ◽

Corrosive Liquid ◽

Properties Of Soil

The present study provides an effective technique of improving properties of leachate effected soil using bio-enzyme named TERRAZYME.Soil pollution is an consequence especially in a country like INDIA unscientific disposal and dumping of solid waste leads to generation of leachate. High concentration of leachate has less pH value (i.e., acidic in nature) which reduces the particle size. Due to reduction in particle size the properties of soil are also effected. A laboratory testing program was carried out on soil to determine the behavior of leachate effected soil and terrazyme. For that we performed particle size analysis, compaction and California bearing ratio tests on 5% 10% and 15% leachate effected soil to vary the degree of contamination.Terrazyme is a natural non-toxic, non-flammable, non-corrosive liquid enzyme formulated fermented from vegetables that improves the engineering qualities of soil, facilitates higher soil compaction densities and increases stability. It can be used as soil stabilizer and also improve CBR value, durability and decreases the omc, plasticity index of soil. Terrazyme on soil is permanent and soil becomes biodegradable in nature.So we used terrazyme as a stabilizing agent to improve the properties of leachate effected soil. By using this enzyme we can improve the strength effectively, mainly California bearing ratio

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Application of PAC and flocculants for improving settling of solid particles in oilfield wastewater with high salinity and Ca2+

Water Science & Technology ◽

10.2166/wst.2017.334 ◽

2017 ◽

Vol 76 (6) ◽

pp. 1399-1408 ◽

Cited By ~ 1

Author(s):

Guoliang Liu ◽

Fusheng Zhang ◽

Yuanzhi Qu ◽

He Liu ◽

Lun Zhao ◽

...

Keyword(s):

Particle Size ◽

Calcium Ion ◽

Suspended Solids ◽

High Salinity ◽

Particle Size Analysis ◽

Solid Particles ◽

Size Analysis ◽

High Concentration ◽

Particle Settling ◽

High Calcium

The suspended solids in wastewater from Rekabak oilfield, Kazakhstan, were characterized and treated with flocculants to enhance settling. The wastewater contained a high concentration of total dissolved solids and calcium ion. Scanning electron microscopy and energy dispersive X-ray analyses showed that suspended solids were mainly composed of corrosion products (iron oxides) and silicon dioxide particles. Also, much salt deposition from wastewater caused a large increase in the suspended solids value. The settling of solid particles in wastewater was investigated by turbidity decrease within 60 min. The particle settling was enhanced by adding polyaluminum chloride (PAC) as coagulant and hydrolyzed polyacryamide (HPAM) or cationic polyacrylamide (CPAM) as flocculant. At optimal dose, the particle settling ability with PAC and CPAM was better than that with PAC and HPAM. Particle size analysis showed that HPAM or CPAM with high molecular weight played an important role for enlarging the particle size. The experiments with simulated wastewater showed that particle settling by using HPAM deteriorated significantly compared to that by CPAM at high calcium ion. This study provides further understanding about the effect of high salinity and Ca2+ on solids formation, flocculant performance and particle settling. Meanwhile, the results are also helpful to develop novel flocculants used for high salinity wastewater.

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Synthesis and Dispersion of PZT Ultra-Fine Powders

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.179 ◽

2006 ◽

Vol 514-516 ◽

pp. 179-183

Author(s):

Ai Ying Wu ◽

Dirk Van Genechten ◽

Paula M. Vilarinho ◽

Marlies K. Van Bael

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Sol Gel ◽

Aqueous Media ◽

Particle Size Analysis ◽

Size Analysis ◽

Particle Charge ◽

Powder Morphology ◽

Fine Powders ◽

Particle Size Analyzer

In the current work two different routes, an alkoxide based sol-gel and an aqueous solution-gel route, were used to synthesize PZT (30/70) powders. The phase purity, morphology and particle size of both were studied by XRD, TEM and particle size analysis. The dispersion behavior of the powders in water was investigated by means of light scattering particle size analyzer and zeta potential measurements. The extent to which powder morphology, synthesis route and particle charge state relate to the resulting dispersion behaviour was established. Alkoxide sol-gel derived powders are better dispersed in aqueous media than aqueous solution-gel derived powders.

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Citrate-Zn/Al Layered Double Hydroxide as Adsorbent of Congo Red from Aqueous Solution

Mediterranean Journal of Chemistry ◽

10.13171/mjc02003131281al ◽

2020 ◽

Vol 10 (3) ◽

pp. 220-232

Author(s):

Nurlisa Hidayati ◽

Neza Rahayu Palapa ◽

Bakri Rio Rahayu ◽

Risfidian Mohadi ◽

Elfita Elfita ◽

...

Keyword(s):

Aqueous Solution ◽

Layered Double Hydroxide ◽

Congo Red ◽

Physical Adsorption ◽

Freundlich Isotherm ◽

Interlayer Distance ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Bet Analysis ◽

Double Hydroxide

Layered double hydroxide (LDH) of Zn/Al and citrate-Zn/Al was prepared and used as an adsorbent of Congo red from aqueous solution. LDH was characterized by X-ray, FTIR, and BET analysis. Adsorption of Congo red was studied through kinetic, isotherm, and thermodynamic analyses. Zn/Al LDH has diffraction at 10.29o (003) with interlayer distance 8.59 Å and citrate-Zn/Al LDHs have anomalous diffraction at 7.57o (003) with interlayer distance 11.68 Å. The surface area of citrate-Zn/Al (40.50 m2 g-1) has higher than pristine LDH (1.97 m2 g-1). Adsorption of Congo red was conducted at pH 6 for Zn/Al LDH and at pH 8 for citrate-Zn/Al LDH. Adsorption of Congo red on both LDHs follows the pseudo-second-order kinetic model. The isotherm parameter follows the Freundlich isotherm model with maximum adsorption capacity 166.67 mg g-1 for Zn/Al and 249.99 mg g-1 for citrate-Zn/Al LDH. Adsorption of Congo red on both LDHs was classified as physical adsorption with energy 4.085-4.148 kJ mol-1.

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