ADSORPTION KINETICS, ISOTHERMS, THERMODYNAMICS STUDIES ON THE REMOVAL OF CONGO RED DYE USING ANNONA SQUAMOSA (CUSTARD APPLE) PEEL

The present study evaluates the feasibility of an adsorbent prepared from Annona squamosa (custard apple) peel, in removing Congo red dye from its aqueous solution. Batch experiments were carried out to study the effect of various parameters like pH (2-8), adsorbent dose (0.005-0.5 g/100mL), contact time (5-120 min), initial dye concentration (25-200 mg/L) and temperature (298-308 K) to determine its effectiveness as an adsorbent. Maximum dye removal attained at pH 2, adsorbent dose 0.1 g/100mL in equilibrium time of 45 min at 308K. Adsorption kinetics using pseudo-first order and pseudo-second order models, and adsorption isotherm using Langmuir and Freundlich models were studied. The adsorption process was found to follow pseudo-second order kinetic model and more favourably described the Langmuir isotherm model. The Gibbs free energy was found to be negative, signifying the spontaneous nature of the adsorption process. Removal of Congo red dye from its aqueous solution by custard apple peel was found to be an endothermic process. The results of the present study suggest that custard apple can be effectively used as an adsorbent to remove Congo red dye from aqueous solution.

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Adsorptive Removal of Congo red dye from wastewater using Fenugreek Powder

10.20944/preprints202004.0173.v1 ◽

2020 ◽

Author(s):

Neha bhadauria ◽

Arjun Suresh

Keyword(s):

Aqueous Solution ◽

Congo Red ◽

Contact Time ◽

Adsorption Process ◽

Dye Adsorption ◽

Textile Dye ◽

Adsorptive Removal ◽

Congo Red Dye ◽

Red Dye ◽

Maximum Removal

The present study analyzed the efficiency of a naturally derived fenugreek powder for removal of Congo red dye from the aqueous solution. The flocculation Studies on Congo Red (CR) a hazardous, textile dye onto Fenugreek Powder and its adsorption was analyzed. Fenugreek Powder is Eco-friendly, biodegradable and locally available in the market. The dye adsorption process was performed in different batches at varying pH, dye concentration, adsorbent concentration and contact time to get the best results. The result showed that the maximum removal of dye was 42.4% with 10mg/l of Fenugreek powder at pH 4.

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Adsorption of congo red dye from aqueous solution onto amino-functionalized silica gel

Engenharia Sanitaria e Ambiental ◽

10.1590/s1413-41522018172982 ◽

2018 ◽

Vol 23 (6) ◽

pp. 1053-1060 ◽

Cited By ~ 9

Author(s):

Raquel Studart de Farias ◽

Hugo Leonardo de Brito Buarque ◽

Mabel Ribeiro da Cruz ◽

Luana Meg Freitas Cardoso ◽

Tamyris de Aquino Gondim ◽

...

Keyword(s):

Aqueous Solution ◽

Silica Gel ◽

Congo Red ◽

Second Order ◽

Functionalized Silica ◽

Congo Red Dye ◽

Major Mode ◽

Effects Of Ph ◽

Pseudo Second Order ◽

Red Dye

ABSTRACT This study investigates the potential use of amino-functionalized silica gel as an adsorbent for the recovering of congo red dye from aqueous solution. The effects of pH, contact time, and temperature were determined and evaluated. Equilibrium isotherms were also studied. The adsorption kinetics was modeled by pseudo-first order and pseudo-second order. Furthermore, desorption of congo red was preliminarily studied. The pH range from 4.5 to 7.0 was favorable for the adsorption of congo red onto amine modified silica at 25ºC. Higher adsorption capacity was obtained at 50ºC. Langmuir and Freundlich models were fitted to the adsorption equilibrium data. The best fittings were obtained with the pseudo-second order and Langmuir model for kinetics and equilibrium, respectively. Desorption studies suggest that ion exchange might be the major mode of adsorption. KOH solution was the best desorbing agent for recovering the adsorbed dye.

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Facile Synthesis of Cu-Zn Binary Oxide Coupled Cadmium Tungstate (Cu-ZnBO-Cp-CT) with Enhanced Performance of Dye Adsorption

Water ◽

10.3390/w13223287 ◽

2021 ◽

Vol 13 (22) ◽

pp. 3287

Author(s):

Bushra Fatima ◽

Basem Al Alwan ◽

Sharf Ilahi Siddiqui ◽

Rabia Ahmad ◽

Mohammed Almesfer ◽

...

Keyword(s):

Aqueous Solution ◽

Partition Coefficient ◽

Congo Red ◽

Adsorption Process ◽

Adsorption Equilibrium ◽

Binary Oxide ◽

Cadmium Tungstate ◽

Congo Red Dye ◽

Prepared Composite ◽

Red Dye

This study reports the synthesis of copper–zinc binary oxide coupled cadmium tungstate through a simple bio-precipitation method followed by calcination at 600 °C and its adsorption application. The characterization analysis reveals that the prepared composite has low particles size (nano-range), high porosity, and functional groups on the surface. The calcination of sample at 600 °C causes some essential function groups to disappear on the surface. Prepared composite was found to be effective adsorptive material to treat Congo red dye in aqueous solution. 2.5 g L−1 dose of adsorbent could remove more than 99% Congo red dye from 10 mg L−1 solution and more than 80% Congo red dye from 60 mg L−1 aqueous solution. The maximum adsorption capacity of present adsorbent was calculated to be 19.6 mg Congo red per gram of adsorbent. Isotherms analysis suggested a physio-chemical adsorption process. Thermodynamic analysis revealed a exothermic and feasible adsorption process. Adsorption rate was well explained by pseudo second order kinetics. The rate determining step was intra-particle diffusion evaluated from the Weber-Morris plot. To assess the adsorption performance of present adsorbent for Congo red dye the partition coefficient and adsorption equilibrium capacity were compared with other adsorbents. The partition coefficient and adsorption equilibrium values for 10 mg L−1 aqueous solution were found to be approximately 83.3 mg g−1 µM−1 and 4.0 mg g−1 at 30 °C and 7.0 pH using 2.5 g L−1 adsorbent. The value of partition coefficient was found to be higher than previous reported zinc oxide coupled cadmium tungstate having partition coefficient = as 21.4 mg g−1 µM−1 at 30 °C and 7.0 pH using 2.0 g L−1 adsorbent (Fatima, B.; Siddiqui, S.I.; Nirala, R.K. et al., Environ. Poll. 2021, 271, 116401). These results suggested that present adsorption technology is efficient for wastewater treatment.

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