scholarly journals Porosity Characteristics of Activated Carbons Derived from Olive Oil Wastes Impregnated with H3PO4

2000 ◽  
Vol 18 (4) ◽  
pp. 373-383 ◽  
Author(s):  
Laila B. Khalil ◽  
Badie S. Girgis ◽  
Tarek A.M. Tawfik
Keyword(s):  
Olive Oil ◽  
Activated Carbons ◽  
Bond Cleavage ◽  
Low Cost ◽  
Chemical Activation ◽  
High Capacity ◽  
Acid Catalyst ◽  
Nitrogen Adsorption ◽  
Raw Material ◽  
Nitrogen Adsorption Isotherms

Locally discarded olive oil waste was tested as a potential raw material for the preparation of activated carbons. Chemical activation by impregnation with H3PO4 was employed using acid solutions of varying concentration in the range 30–70% followed by thermal treatment at 500–700°C. The development of porosity was followed from an analysis of the nitrogen adsorption isotherms obtained at 77 K by applying standard BET and t-plot methods. Carbons with low to moderate surface areas (273–827 m2/g) and total pore volumes (0.27–0.69 ml/g), containing essentially micropores with diameters of 8.2 Å up to 12.4 Å were obtained. Increasing the concentration of impregnant led to the development of porosity with the optimum being attained at 60% H3PO4. Phosphoric acid is visualized as acting both as an acid catalyst promoting bond-cleavage reactions and the formation of new crosslinks and also as a reactant which combines with organic species to form phosphate and polyphosphate bridges which connect and crosslink biopolymer fragments. The present study suggests many applications for environmental pollution control, firstly by utilizing accumulating low-cost agricultural by-products and secondly by producing a multi-purpose high-capacity adsorbent useful in the remediation of micropollutants in various water courses.

scholarly journals Comparison of Surface and Structural Properties of Carbonaceous Materials Prepared by Chemical Activation of Tomato Paste Waste: The Effects of Activator Type and Impregnation Ratio

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Nurgul Ozbay ◽  
Adife Seyda Yargic
Keyword(s):  
Activated Carbon ◽  
Activated Carbons ◽  
Low Cost ◽  
Chemical Activation ◽  
Nitrogen Adsorption ◽  
Xrd Analysis ◽  
Point Of Zero Charge ◽  
Activation Process ◽  
X Ray ◽  
Tomato Paste

Activated carbons were prepared by carbonization of tomato paste processing industry waste at 500°C followed by chemical activation with KOH, K2CO3, and HCl in N2 atmosphere at low temperature (500°C). The effects of different activating agents and impregnation ratios (25, 50, and 100 wt.%) on the materials’ characteristics were examined. Precursor, carbonized tomato waste (CTW), and activated carbons were characterized by using ultimate and proximate analysis, thermogravimetric analysis (TG/DTG), Fourier transform-infrared (FT-IR) spectroscopy, X-ray fluorescence (XRF) spectroscopy, point of zero charge measurements (pHPZC), particle size analyzer, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, nitrogen adsorption/desorption isotherms, and X-ray diffraction (XRD) analysis. Activation process improved pore formation and changed activated carbons’ surface characteristics. Activated carbon with the highest surface area (283 m3/g) was prepared by using 50 wt.% KOH as an activator. According to the experimental results, tomato paste waste could be used as an alternative precursor to produce low-cost activated carbon.

scholarly journals Natural and Chemically Modified Post-Mining Clays—Structural and Surface Properties and Preliminary Tests on Copper Sorption

Minerals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 704
Author(s):  
Beata Jabłońska ◽  
Mark Busch ◽  
Andriy V. Kityk ◽  
Patrick Huber
Keyword(s):  
Structural Properties ◽  
Surface Properties ◽  
Structural Changes ◽  
Low Cost ◽  
Fractal Dimensions ◽  
Nitrogen Adsorption ◽  
Raw Material ◽  
Water Pretreatment ◽  
Maximum Sorption ◽  
Nitrogen Adsorption Isotherms

The structural and surface properties of natural and modified Pliocene clays from lignite mining are investigated in the paper. Chemical modifications are made using hydrofluoric acid (HF), sulfuric acid (H2SO4), hydrochloric acid (HCl), nitric acid (HNO3), sodium hydroxide (NaOH), and hydrogen peroxide (H2O2), at a concentration of 1 mol/dm3. Scanning electron microscopy is used to detect the morphology of the samples. Nitrogen adsorption isotherms were recorded to determine the specific surface area (SSA), mesoporosity, microporosity, and fractal dimensions. The raw clay has an SSA of 66 m2/g. The most promising changes in the structural properties are caused by modifications with HF or H2SO4 (e.g., the SSA increased by about 60%). In addition, the raw and modified clays are used in preliminary tests with Cu(II) sorption, which were performed in batch static method at initial Cu(II) concentrations of 25, 50, 80, 100, 200, 300, and 500 mg/dm3 in 1% aqueous suspensions of the clayey material. The maximum sorption of Cu(II) on the raw material was 15 mg/g. The structural changes after the modifications roughly reflect the capabilities of the adsorbents for Cu(II) adsorption. The modifications with HF and H2SO4 bring a similar improvement in Cu(II) adsorption, which is around 20–25% greater than for the raw material. The structural properties of investigated clays and their adsorptive capabilities indicate they could be used as low-cost adsorbents (e.g., for industrial water pretreatment).

scholarly journals Preparation of Activated Carbon from the Biodegradable film for Co2 Capture Applications

2018 ◽  
Vol 20 (3) ◽  
pp. 75-80
Author(s):  
J. Serafin ◽  
A.K. Antosik ◽  
K. Wilpiszewska ◽  
Z. Czech
Keyword(s):  
Activated Carbon ◽  
Activated Carbons ◽  
Low Cost ◽  
Chemical Activation ◽  
Total Pore Volume ◽  
Nitrogen Adsorption ◽  
Waste Utilization ◽  
Co2 Production ◽  
Biodegradable Film ◽  
Adsorption Desorption

Abstract In this work for the fi rst time, activated carbons were prepared from carboxymethyl fi lm (low-cost carboxymethyl fi lm waste), using chemical activation with potassium hydroxide. The samples were characterized by nitrogen adsorption-desorption at 77 K, XRD, SEM methods. The high values of the specifi c surface area and total pore volume were achieved and were equal to 2064 m2/g and 1.188 cm3/g, respectively. Waste from the fi lm can be immediately utilized without CO2 production. This is the environmentally friendly way of waste utilization. Through this process, we can protect our environment. This study showed that the activated carbon obtained from carboxymethyl fi lm waste can be used as a good adsorbent for CO2 adsorption.

scholarly journals Fitting Biochars and Activated Carbons from Residues of the Olive Oil Industry as Supports of Fe- Catalysts for the Heterogeneous Fenton-Like Treatment of Simulated Olive Mill Wastewater

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 876 ◽  
Author(s):  
Bruno M. Esteves ◽  
Sergio Morales-Torres ◽  
Francisco J. Maldonado-Hódar ◽  
Luis M. Madeira
Keyword(s):  
Olive Oil ◽  
Catalyst Deactivation ◽  
Activated Carbons ◽  
Low Cost ◽  
Chemical Activation ◽  
Textural Properties ◽  
Oil Industry ◽  
Olive Mill Wastewater ◽  
Heterogeneous Fenton ◽  
Olive Mill

A series of biochars and activated carbons (ACs) was prepared combining carbonization and physical or chemical activation of cheap and abundant residues of the olive oil industry. These materials were used as Fe-support to develop low-cost catalysts for the heterogeneous Fenton-like oxidation of simulated olive mill wastewater (OMW), the highly pollutant effluent generated by this agroindustry. Commercial ACs were also used as reference. All catalysts prepared were extensively characterized and results related with their performances in the catalytic wet peroxide oxidation (CWPO). Results showed a linear relationship of the textural properties of the catalysts with the adsorptive and catalytic performance, as well as the preferential adsorption and degradation of some phenolic compounds (caffeic and gallic acids) by specific interactions with the catalysts’ surface. Despite the best performance of catalysts developed using commercial supports, those prepared from agro-industrial residues present some advantages, including a smaller catalyst deactivation by iron leaching. CWPO results show that catalysts from physically activated olive stones are the most promising materials, reaching total organic carbon and toxicity reductions of 35% and 60%, respectively, as well an efficient use of H2O2, comparable with those obtained using commercial supports. This approach showed that the optimized treatment of this type of residues will allow their integration in the circular economic process of the olive oil production.

Characteristics of Activated Carbon Produced from Rubber Seed Shell by Using Different Methods of Chemical Activation with KOH

2015 ◽  
Vol 781 ◽  
pp. 659-662 ◽  
Author(s):  
Thanchanok Pagketanang ◽  
Prasong Wongwicha ◽  
Mallika Thabuot
Keyword(s):  
Activated Carbon ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Volume Ratio ◽  
Nitrogen Adsorption ◽  
Activation Method ◽  
Bet Surface Area ◽  
Average Pore ◽  
Rubber Seed ◽  
Nitrogen Adsorption Isotherms

Rubber-seed shell was selected as the precursor for the preparation of activated carbon by chemical activation with KOH as an activating agent. Impregnation-Activation Method and Carbonization-Impregnation-Activation Method were investigated with different concentration of KOH solution. Rubber-seed shell activated carbons were characterized by using scanning electron microscope, fourier transform infared spectroscopy and nitrogen adsorption isotherms. The results present that the first method which impregnation of precursor in 2%wt. KOH solution with the ratio of 300 g/l for 24 hrs before thermal activation at 700°C for 2 hrs under 2 cm3/min of nitrogen flow, was satisfied to prepare the Rubber-seed shell activated carbon. Products with maximum BET surface area, average pore diameter and volume ratio of micropores to mesopores were equal to 429 m2/g, 2.09 nm and 4.19, respectively.

Preparation and Characterization of Activated Carbon from Reedy Grass Leaves by Chemical Activation with KOH

2014 ◽  
Vol 881-883 ◽  
pp. 579-583 ◽  
Author(s):  
Ling Zhi Chen ◽  
Dong Xu Miao ◽  
Xiao Jie Feng ◽  
Jian Zhong Xu
Keyword(s):  
Iodine Number ◽  
Surface Area ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Weight Ratio ◽  
Raw Material ◽  
Bet Surface Area ◽  
Activation Temperature ◽  
Impregnation Ratio ◽  
Dta Analysis

Activated carbons (AC) were produced by chemical activation with potassium hydroxide (KOH) at 800°C from chars that were carbonized from reedy grass leaves at 450°C in N2atmosphere. The effects of the weight ratio of KOH/char ( impregnation ratio), activation temperature and duration time were examined. Adsorption capacity was demonstrated with iodine number. BET surface area, pore volume and pore size of activated carbons were characterized by N2adsorption isotherms. The maximum surface area and iodine number of the AC was 1100 m2/g and 1080 mg/g produced at 800°C for2h and impregnation ratio is 4:1.The characteristics of activated carbons were determined by Infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). Thermal gravimetry (TG/DTA) analysis of raw material was carried out.

scholarly journals Synthesis and characterization of graphene layers from rice husks

2018 ◽  
pp. 12-18
Author(s):  
Makpal Seitzhanova ◽  
Dmitry Chenchik ◽  
Mukhtar Yeleuov ◽  
Zulkhair Mansurov ◽  
Roberto Di Capua ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Rice Husk ◽  
Renewable Resources ◽  
Large Scale ◽  
Low Cost ◽  
Chemical Activation ◽  
Raw Material ◽  
Graphene Layers ◽  
Naoh Solution

In this work, a method of obtaining graphene layers from natural source specifically from rice husk was developed. A rice husk (RH) was used as a raw material, and potassium hydroxide was used as activation agent. The graphene layers were obtained after four successive stages: pre-carbonization, desilication in 1M NaOH solution, chemical activation and exfoliation of the carbonized rice husk (CRH). The obtained samples were studied using Raman spectroscopy, TEM and SEM; the Raman peaks evidenced the presence of graphene multilayers in the sample. A detailed observation of Raman spectroscopy showed that the obtained samples with ratio of 1/4 and 1/5 (RH/KOH) consisted of graphene layers with a high content of amorphous component. The yield of the product was ~ 3% by weight. This study can provide a new way to the large-scale synthesis of low-cost single and multi-layered graphene using rice husk or other renewable resources.

scholarly journals Evaluation of adsorptive desulfurization performance and economic applicability comparison of activated carbons prepared from various carbon sources

RSC Advances ◽  
2020 ◽  
Vol 10 (66) ◽  
pp. 40329-40340
Author(s):  
Kun Chen ◽  
Weining Li ◽  
Bernard Wiafe Biney ◽  
Zhuo Li ◽  
Jiahua Shen ◽  
...  
Keyword(s):  
Preparation Method ◽  
Activated Carbons ◽  
Low Cost ◽  
Carbon Sources ◽  
Environmentally Friendly ◽  
Raw Material ◽  
Adsorptive Desulfurization

Selection and preparation method of a low-cost, environmentally-friendly desulfurization adsorbent raw material.

scholarly journals Highly Porous Carbons Synthesized from Tannic Acid via a Combined Mechanochemical Salt-Templating and Mild Activation Strategy

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1826
Author(s):  
Sylwia Głowniak ◽  
Barbara Szczęśniak ◽  
Jerzy Choma ◽  
Mietek Jaroniec
Keyword(s):  
Specific Surface ◽  
Tannic Acid ◽  
Activated Carbons ◽  
Low Cost ◽  
Chemical Activation ◽  
Total Pore Volume ◽  
Co2 Uptake ◽  
Potassium Oxalate ◽  
Templating Method ◽  
Highly Porous

Highly porous activated carbons were synthesized via the mechanochemical salt-templating method using both sustainable precursors and sustainable chemical activators. Tannic acid is a polyphenolic compound derived from biomass, which, together with urea, can serve as a low-cost, environmentally friendly precursor for the preparation of efficient N-doped carbons. The use of various organic and inorganic salts as activating agents afforded carbons with diverse structural and physicochemical characteristics, e.g., their specific surface areas ranged from 1190 m2·g−1 to 3060 m2·g−1. Coupling the salt-templating method and chemical activation with potassium oxalate appeared to be an efficient strategy for the synthesis of a highly porous carbon with a specific surface area of 3060 m2·g−1, a large total pore volume of 3.07 cm3·g−1 and high H2 and CO2 adsorption capacities of 13.2 mmol·g−1 at −196 °C and 4.7 mmol·g−1 at 0 °C, respectively. The most microporous carbon from the series exhibited a CO2 uptake capacity as high as 6.4 mmol·g−1 at 1 bar and 0 °C. Moreover, these samples showed exceptionally high thermal stability. Such activated carbons obtained from readily available sustainable precursors and activators are attractive for several applications in adsorption and catalysis.

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