High-performance removal of methyl mercaptan by nitrogen-rich coconut shell activated carbon

Nitrogen-rich coconut shell activated carbons were prepared with high CH3SH capacity and easy regeneration. The catalytic activity is closely related to the contents of pyridinic nitrogen and quaternary nitrogen.

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Equilibrium and Kinetics of CO2 Adsorption by Coconut Shell Activated Carbon Impregnated with Sodium Hydroxide

Processes ◽

10.3390/pr9020201 ◽

2021 ◽

Vol 9 (2) ◽

pp. 201

Author(s):

Chaiyot Tangsathitkulchai ◽

Suravit Naksusuk ◽

Atichat Wongkoblap ◽

Poomiwat Phadungbut ◽

Prapassorn Borisut

Keyword(s):

Activated Carbon ◽

Sodium Hydroxide ◽

Co2 Adsorption ◽

Activated Carbons ◽

Nitrogen Adsorption ◽

Coconut Shell ◽

Type I ◽

Equilibrium And Kinetics ◽

Coconut Shell Activated Carbon ◽

Kinetics Of

The equilibrium and kinetics of CO2 adsorption at 273 K by coconut-shell activated carbon impregnated with sodium hydroxide (NaOH) was investigated. Based on nitrogen adsorption isotherms, porous properties of the tested activated carbons decreased with the increase of NaOH loading, with the decrease resulting primarily from the reduction of pore space available for nitrogen adsorption. Equilibrium isotherms of CO2 adsorption by activated carbons impregnated with NaOH at 273 K and the pressure up to 100 kPa displayed an initial part of Type I isotherm with most adsorption taking place in micropores in the range of 0.7–0.9 nm by pore-filling mechanisms. The amount of CO2 adsorbed increased with the increase of NaOH loading and passed through a maximum at the optimum NaOH loading of 180 mg/g. The CO2 isotherm data were best fitted with the three-parameter Sips equation, followed by Freundlich and Langmuir equations. The pore diffusion model, characterized by the effective pore diffusivity (De), could well describe the adsorption kinetics of CO2 in activated carbons impregnated with NaOH. The variation of De with the amount of CO2 adsorbed showed three consecutive regions, consisting of a rapid decrease of De for CO2 loading less than 40 mg/g, a relatively constant value of De for the CO2 loading of 40–80 mg/g and a slow decrease of De for the CO2 loading of 80–200 mg/g. The maximum De occurred at the optimum NaOH loading of 180 mg/g, in line with the equilibrium adsorption results. The values of De varied from 1.1 × 10−9 to 5.5 × 10−9 m2/s, which are about four orders of magnitude smaller than the molecular diffusion of CO2 in air. An empirical correlation was developed for predicting the effective pore diffusivity with the amount of CO2 adsorbed and NaOH loading.

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Comparative Analysis of Activated Carbons from African Teak (Iroko) Wood and Coconut Shell in Palm Oil Bleaching

10.21467/preprints.350 ◽

2021 ◽

Author(s):

Davidson C Onwumelu

Keyword(s):

Activated Carbon ◽

Palm Oil ◽

Activated Carbons ◽

Volatile Matter ◽

Proximate Analysis ◽

Coconut Shell ◽

Adsorbent Dosage ◽

Hot Air ◽

Fuller’S Earth ◽

Coconut Shell Activated Carbon

This study compares the effectiveness of activated carbons from the African Teak/Iroko wood (Milicia excelsia) and coconut shell as adsorbents in Crude Palm Oil (CPO) bleaching. This was done in order to source for local agro-waste substitutes for the imported Fuller’s earth. The materials were activated using analytical grade CaCl2 in 25% solution at a temperature of 109OC in a laboratory hot air oven. The obtained activated carbon samples were subjected to proximate analysis to ascertain their percentage ash, moisture, volatile matter and fixed carbon contents. The CPO to be analysed was degummed, neutralized and further bleached using 2g, 4g, 6g, 8g, 10g, 12g and 14g of the adsorbent samples at a temperature of 130OC after which the obtained oils were analysed and results plotted. It was observed that the bleached oil samples generally had reduced specific gravity, opacity, colour, and free fatty acid (FFA) compared to the CPO. It was also observed that the opacity, colour, and FFA reduced as the adsorbent dosage increased. Conversely, the percentage colour reduction and the percentage FFA reduction increased with adsorbent dosage. Overall, the oil samples bleached by activated carbon from the African Teak/Iroko wood exhibited more desirable properties than the ones bleached by the coconut shell activated carbon.

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Sustainable development of coconut shell activated carbon (CSAC) & a magnetic coconut shell activated carbon (MCSAC) for phenol (2-nitrophenol) removal

RSC Advances ◽

10.1039/c6ra19756f ◽

2016 ◽

Vol 6 (88) ◽

pp. 85390-85410 ◽

Cited By ~ 18

Author(s):

Ankur Sarswat ◽

Dinesh Mohan

Keyword(s):

Sustainable Development ◽

Activated Carbon ◽

Activated Carbons ◽

Coconut Shell ◽

Slow Pyrolysis ◽

Coconut Shell Activated Carbon

Slow pyrolysis coconut shell (CSAC) and magnetic coconut shell (MCSAC) activated carbons were prepared, characterized and used for aqueous 2-nitrophenol (2-NP) removal.

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Refining micropore capacity of activated carbon derived from coconut shell via deashing post-treatment

BioResources ◽

10.15376/biores.15.4.7749-7769 ◽

2020 ◽

Vol 15 (4) ◽

pp. 7749-7769

Author(s):

Kit Ling Chin ◽

Chuan Li Lee ◽

Paik San H'ng ◽

Umer Rashid ◽

Md Tahir Paridah ◽

...

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Lignocellulosic Biomass ◽

Activated Carbons ◽

Functional Materials ◽

Ash Content ◽

Post Treatment ◽

Coconut Shell ◽

Novel Approach ◽

Coconut Shell Activated Carbon

The discovery of new methods to control porosity and microarchitecture may lead to the refinement of carbon materials from lignocellulose as advanced functional materials. However, the high ash content on the surface of lignocellulosic biomass reduces the surface area and adsorption properties of the activated carbon. This study presents a novel approach, using a deashing post-treatment as the pore generator, to increase the quality of the activated carbon. The micropore capacity was improved by deashing post-treatment with distilled water, where 80% of the total pore ratio of the activated carbon was occupied with micropores. Ultrasonic treatment was able to penetrate deeper into the structure of coconut shell activated carbon, creating cavities and pores, thus increasing the surface area. Understanding the effects of these new controlling methods on pore refinement can elucidate the microporous fabrication of other activated carbons from high ash-content lignocellulosic biomass.

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Use of activated carbon to remove undesirable residual amylase from refinery streams

Sugar Industry ◽

10.36961/si18170 ◽

2017 ◽

pp. 96-103 ◽

Cited By ~ 1

Author(s):

Gillian Eggleston ◽

Isabel Lima ◽

Emmanuel Sarir ◽

Jack Thompson ◽

John Zatlokovicz ◽

...

Keyword(s):

Activated Carbon ◽

High Temperature ◽

High Performance ◽

Activated Carbons ◽

Amylase Activity ◽

Sugar Industry ◽

End User ◽

Customer Complaints ◽

Carry Over ◽

Very High

In recent years, there has been increased world-wide concern over residual (carry-over) activity of mostly high temperature (HT) and very high temperature (VHT) stable amylases in white, refined sugars from refineries to various food and end-user industries. HT and VHT stable amylases were developed for much larger markets than the sugar industry with harsher processing conditions. There is an urgent need in the sugar industry to be able to remove or inactivate residual, active amylases either in factory or refinery streams or both. A survey of refineries that used amylase and had activated carbon systems for decolorizing, revealed they did not have any customer complaints for residual amylase. The use of high performance activated carbons to remove residual amylase activity was investigated using a Phadebas® method created for the sugar industry to measure residual amylase in syrups. Ability to remove residual amylase protein was dependent on the surface area of the powdered activated carbons as well as mixing (retention) time. The activated carbon also had the additional benefit of removing color and insoluble starch.

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