scholarly journals Activated Carbon from Agricultural Wastes for Adsorption of Organic Pollutants

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5105
Author(s):  
Magdalena Blachnio ◽  
Anna Derylo-Marczewska ◽  
Barbara Charmas ◽  
Malgorzata Zienkiewicz-Strzalka ◽  
Viktor Bogatyrov ◽  
...  

Agricultural waste materials (strawberry seeds and pistachio shells) were used for preparation of activated carbons by two various methods. Chemical activation using acetic acid and physical activation with gaseous agents (carbon dioxide and water vapor) were chosen as mild and environmentally friendly methods. The effect of type of raw material, temperature, and activation agent on the porous structure characteristics of the materials was discussed applying various methods of analysis. The best obtained activated carbons were characterized by high values of specific surface area (555–685 m2/g). The Guinier analysis of small-angle X-ray scattering (SAXS) curves showed that a time of activation affects pore size. The samples activated using carbon dioxide were characterized mostly by the spherical morphology of pores. Adsorbents were utilized for removal of the model organic pollutants from the single- and multicomponent systems. The adsorption capacities for the 4-chloro-2-methyphenoxyacetic acid (MCPA) removal were equal to 1.43–1.56 mmol/g; however, for adsorbent from strawberry seeds it was much lower. Slight effect of crystal violet presence on the MCPA adsorption and inversely was noticed as a result of adsorption in different types of pores. For similar herbicides strong competition in capacity and adsorption rate was observed. For analysis of kinetic data various equations were used.

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3136 ◽  
Author(s):  
Deneb Peredo-Mancilla ◽  
Imen Ghouma ◽  
Cecile Hort ◽  
Camelia Matei Ghimbeu ◽  
Mejdi Jeguirim ◽  
...  

The aim of the present work is to study the effect of different activation methods for the production of a biomass-based activated carbon on the CO 2 and CH 4 adsorption. The influence of the activation method on the adsorption uptake was studied using three activated carbons obtained by different activation methods (H 3 PO 4 chemical activation and H 2 O and CO 2 physical activation) of olive stones. Methane and carbon dioxide pure gas adsorption experiments were carried out at two working temperatures (303.15 and 323.15 K). The influence of the activation method on the adsorption uptake was studied in terms of both textural properties and surface chemistry. For the three adsorbents, the CO 2 adsorption was more important than that of CH 4 . The chemically-activated carbon presented a higher specific surface area and micropore volume, which led to a higher adsorption capacity of both CO 2 and CH 4 . For methane adsorption, the presence of mesopores facilitated the diffusion of the gas molecules into the micropores. In the case of carbon dioxide adsorption, the presence of more oxygen groups on the water vapor-activated carbon enhanced its adsorption capacity.


Processes ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 300 ◽  
Author(s):  
Dongdong Liu ◽  
Xiaoman Zhao ◽  
Rui Su ◽  
Zhengkai Hao ◽  
Boyin Jia ◽  
...  

At present, the preparation of highly porous graphitic activated carbons (HPGACs) using the usual physical and chemical activation methods has met a bottleneck. In this study, HPGACs are directly synthesized from lignite at 900 °C. The whole process is completed by a microwave pretreatment, a graphitization conversion of the carbon framework at a low temperature using a small amount of FeCl3 (10–30 wt%), and a subsequent physical activation using CO2. Consequently, the dispersed and mobile iron species, in the absence of oxygen functional groups (removed during the microwave pretreatment), can greatly promote catalytic graphitization during pyrolysis, and, as an activating catalyst, can further facilitate the porosity development during activation. The as-obtained AC-2FeHLH-5-41.4(H) presents a low defect density, high purity, and specific surface area of 1852.43 m2 g−1, which is far greater than the AC-HLH-5-55.6(H) obtained solely by physical activation. AC-2FeHLH-5-41.4(H) as a supercapacitor electrode presents an excellent performance in the further electrochemical measurements. Such a convenient and practical method with low cost proves a scalable method to prepare HPGACs from a wide range of coal/biomass materials for industrial scale-up and applications.


2000 ◽  
Vol 18 (4) ◽  
pp. 373-383 ◽  
Author(s):  
Laila B. Khalil ◽  
Badie S. Girgis ◽  
Tarek A.M. Tawfik

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.


2014 ◽  
Vol 14 (1) ◽  
pp. 82-98
Author(s):  
Andy Mizwar

Limbah rotan dari industri kerajinan dan mebel berpotensi untuk dijadikan sebagai bahan baku pembuatan karbon aktif karena memiliki kandungan holoselulosa dan kadar karbon yang tinggi. Penelitian ini bertujuan untuk menganalisis efektifitas dari aktivasi kimia menggunakan larutan natrium klorida (NaCl) yang dilanjutkan dengan aktivasi fisik dalam pembuatan karbon aktif berbahan dasar  limbah serutan rotan. Pembuatan karbon aktif diawali dengan proses karbonisasi pada suhu 250°C selama 1 jam. Selanjutnya aktivasi kimia menggunakan larutan NaCl dengan variasi konsentrasi 10%, 15% dan 20% serta waktu perendaman selama 10, 15 dan 20 jam. Aktivasi fisik dilakukan dengan pembakaran pada suhu 700°C selama 30 menit. Analisis karakteristik fisik-kimia karbon aktif mengacu pada SNI 06-3730-95, meliputi kadar air, fixed carbon, dan iodine number, sedangkan perhitungan luas permukaan spesifik karbon aktif dilakukan dengan Metode Sears. Hasil penelitian ini menunjukkan bahwa kondisi optimum aktivasi kimia terjadi pada konsentrasi NaCl 10% dan lama perendaman 10 jam dengan hasil analisis kadar air 2.90%, fixed carbon 72.70%, iodine number 994.59 mg/g dan luas permukaan 1587.67 m²/g. Peningkatan fixed carbon, iodine number dan luas permukaan karbon aktif berbanding terbalik dengan peningkatan konsentrasi NaCl dan lama waktu perendaman, sedangkan peningkatan kadar air pada karbon aktif berlaku sebaliknya. Rattan waste from handicraft and furniture industry could potentially be used as raw material of activated carbon due to high content of holoselulosa and carbon. This paper investigates the effectiveness of chemical activation using sodium chloride (NaCl) followed by physical activation in the making of activated carbon-based on rattan shavings waste. Preparation of the activated carbon began with the carbonization process at 250°C for 1 hour. Furthermore chemical activation using a variation of NaCl concentrations 10%, 15% and 20% as well as the time of immersion 10, 15 and 20 hours. Physical activation was done by burning at 700°C for 30 minutes. Analysis of the physical and chemical characteristics of the activated carbon was referred to the SNI 06-3730-95, including of moisture content, fixed carbon and iodine number, while the calculation of the specific surface area was done by the Sears’s method. The results of this study showed that the optimum conditions of chemical activation occurred in impregnation by NaCl 10% for 10 hours. The water content, fixed carbon, iodine number and surface area of activated carbon was 2.90%, 72.70%, 994.59 mg/g and 1587.67 m²/g  respectively. The increase values of fixed carbon, iodine number, and surface area was inversely proportional to the increase of NaCl concentration and the length of impregnation time, while the increase of water content applied vice versa.


2018 ◽  
Vol 142 ◽  
pp. 01005
Author(s):  
Lijuan Gao ◽  
Xiaojun Zheng ◽  
Yaming Zhu ◽  
Xuefei Zhao ◽  
Junxia Cheng

Activated carbons (ACs) were prepared by steam physical activation or KOH chemical activation with the waste external thermal-insulating phenolic foam board as the raw material. The Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) specific area, pore-size distribution and iodine value were used to characterize the properties of ACs. AC-1(with the method of KOH chemical activation) has the iodine value of 2300mg/g, BET specific area of 1293 m2g-1, average pore-size of 2.4 nm, and mainly composed of micropore and relatively small mesopore. AC-2(with the method of steam physical activation) has the iodine value of 1665mg/g. Compared with AC-2, AC-1 had a pore-size distribution with more evenly and relative concentrated, it’s belonging to the high microporosity materials. Actually, chemical activation had more significant influence on destruction of the pore wall than physical activation.


2014 ◽  
Vol 881-883 ◽  
pp. 579-583 ◽  
Author(s):  
Ling Zhi Chen ◽  
Dong Xu Miao ◽  
Xiao Jie Feng ◽  
Jian Zhong Xu

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.


2010 ◽  
Vol 6 (2) ◽  
pp. 1017-1023
Author(s):  
N.R.A. El-Mouhty ◽  
H. M. H. Gad ◽  
A. Y. El-Naggar

This study investigated the applicability of chemically (phosphoric acid) activated bagasse pith and date pits in the adsorption of water pollutants. The textural properties including porous parameters, monolayer equivalent surface area, total pore volumes, average pore radius, Methylene blue number and other physic-chemical characterization were investigated. The activated carbons were analyzed for moisture content, ash content. Ultimate analysis was done by using CHNS analyzer (Cairo University, Micro-analytical Center). To investigate the effect of phosphoric acid on the raw material, thermo gravimetric analysis (TGA) and differential thermo gravimetric (DTG) recordings were determined. The adsorption of heavy metals as pollutants, including Co, Sr, Cu, Cs, Pb, Cd, Ni, Fe, Zn, was studied in a batch experiments. Comparison of date pits activated carbon with commercial activated carbon was done, and the results indicated that using of prepared activated carbon for removal of Co, Sr, Cu, Cs, Pb, Cd, Ni,  Fe, Zn was  more effective than commercial activated carbon.


2021 ◽  
Vol 2049 (1) ◽  
pp. 012067
Author(s):  
Rakhmawati Farma ◽  
Ramadani Putri Anakis ◽  
Irma Apriyani

Abstract Biomass converted into activated carbon (AC) by using physical activation method can form micro-meso pore structure and maintain the interconnected natural pore network of biomass. AC is prepared from the biomass of Parsea Americana seeds (PAS) through a process of pre-carbonization, chemical activation, carbonization and physical activation which is activated at temperatures of 700°C, 800°C, and 900°C. Characterization of physical properties of AC electrodes consisted of X-ray diffraction, Scanning Electron Microscope-Energy Dispersive X-ray and characterization of electrochemical properties of supercapacitor cells using Cyclic Voltametry. The results showed that the microstructure of the AC electrode has a semicrystalline structure characterized by the presence of two sloping peaks at an angle of 2θ around 24° and 44° which corresponded to the hkl (002) and (100) planes, where the lowest Lc value was produced by the PAS-900 sample. The PAS-900 sample had aggregates or lumps with smaller size in small amounts in the presence of micro-mesopores and had the highest carbon content of 94.50% with the highest capacitance value of 203.12 F/g. The temperature of 900°C is the best activation temperature in the process of manufacture AC electrodes from Parsea Americana seeds biomass for supercapacitor cell applications.


Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2047 ◽  
Author(s):  
Katarzyna Januszewicz ◽  
Paweł Kazimierski ◽  
Maciej Klein ◽  
Dariusz Kardaś ◽  
Justyna Łuczak

Pyrolysis of straw pellets and wood strips was performed in a fixed bed reactor. The chars, solid products of thermal degradation, were used as potential materials for activated carbon production. Chemical and physical activation processes were used to compare properties of the products. The chemical activation agent KOH was chosen and the physical activation was conducted with steam and carbon dioxide as oxidising gases. The effect of the activation process on the surface area, pore volume, structure and composition of the biochar was examined. The samples with the highest surface area (1349.6 and 1194.4 m2/g for straw and wood activated carbons, respectively) were obtained when the chemical activation with KOH solution was applied. The sample with the highest surface area was used as an adsorbent for model wastewater contamination removal.


1997 ◽  
Vol 15 (1) ◽  
pp. 59-68 ◽  
Author(s):  
Th. El-Nabarawy ◽  
M.R. Mostafa ◽  
A.M. Youssef

Non-activated carbon ‘A’, physically-activated carbons P1–P4, zinc chloride-activated carbons Z1–Z4 and potassium sulphide-activated carbons K1–K4 were prepared from Maghara coal (Sinai, Egypt). The surface areas of these carbons were determined by investigating the adsorption of carbon dioxide at 298 K and of nitrogen at 77 K. The decolourization powers of the carbons were determined from methylene blue adsorption at 308 K. The adsorption of methanol, benzene, n-hexane, n-octane and α-pinene at 308 K was also determined using equilibrium and flow techniques. The removal of ammonia and phenol from water was investigated on some selected samples. The activated carbons showed high capacities towards the removal of organic pollutants from water and from gas streams via adsorption. Their capacity towards a particular pollutant depends on the method of activation and is related to the textural and/or the chemistry of the carbon surface.


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