A review on the preparation of the activated carbon from agricultural waste material is presented. The physical properties such as proximate and ultimate analysis of agricultural waste material were reviewed. The chemical compositions such as cellulose, hemicelluloses and lignin contents were also discussed. The effects of various parameters on the preparation such as carbonization and activation temperature, time, types of activating agents and impregnation ratio were reviewed. Various physical and chemical processes for the activation of the agricultural residues and their effects on the textural properties such as surface area and pore volume were discussed. The low cost, renewable and relatively less expensive of the agricultural waste were found to be efficiently being converted into wealth. The uses of activated carbon derived from agricultural residues in many fields were evidently proven in the review. The reaction kinetic modeling on the pyrolysis and activation of agricultural wastes were also reviewed.

Agricultural bio-waste materials as potential sustainable precursors used for activated carbon production: A review

http://www.css.cornell.edu/faculty/lehmann/pictures/publ/BioresTechnol%20114,%20644-653,%202012%20Enders.pdf

Characterization of biochars to evaluate recalcitrance and agronomic performance.

Activated carbon is a porous material that has been in many important ages of the human history. Lignocellulosic precursors and biomass sources have become important materials to produce it because their use produces many benefits, mainly environmental. Nowadays, it is possible to find numerous research papers devoted to the synthesis characterization and applications of novel precursors to produce activated carbon. Hence, special attention must be given to the relationship among the selected precursor characteristics, the final microstructure and properties of carbon. The present work provides a summary of research works outlining the use of lignocellulosic–based precursors to obtain activated carbons. A brief description of the characterization techniques for both, the precursors and activated carbons, comprising: physicochemical, micro/nanostructural, surface chemistry, textural and adsorption capacity features is presented. Finally, the application of these materials in adsorption of heavy metals, dyes, volatile organic compounds, gas storage and electrochemical capacitors is also included.

Activated carbon from lignocellulosics precursors: a review of the synthesis methods, characterization techniques and applications.

Activated carbon refers to a wide range of carbonised materials of high degree of porosity and high surface area. Activated carbon has many applications in the environment and industry for the removal, retrieval, separation and modification of various compounds in liquid and gas phases. Selection of the chemical activator agent is a major step controlling the performance and applicability of activated carbon. Here, we review chemical activators used to produce activated carbon. We compare the impregnation method with the physical mixing method used in activating with alkali hydroxides. We selected 81 articles from Google Scholar, PubMed, Scopus, Science Direct, Embase and Medlin databases. Eighteen articles report the activation with potassium hydroxide, 17 with phosphoric acid, 15 with zinc chloride, 11 with potassium carbonate, nine with sodium hydroxide, and 11 with new activating agents. Activation with phosphoric acid is commonly used for lignocellulosic material and at lower temperatures. Zinc chloride generates more surface area than phosphoric acid but is used less due to environmental concerns. Potassium carbonate, in comparison with potassium hydroxide, produces higher yields and a higher surface area for the adsorption of large pollutant molecules such as dyes. Activating with potassium hydroxide in terms of surface area and efficiency shows better results than sodium hydroxide for various applications. Also, the comparison of the physical mixing method and the impregnation method in activation with alkali metals indicates that the activated carbon obtained through physical mixing had a higher porosity than the activated carbon produced by the impregnation method.

Methods for preparation and activation of activated carbon: a review

Biochar production and use are part of the modern agenda to recycle wastes, and to retain nutrients, pollutants, and heavy metals in the soil and to offset some greenhouse gas emissions. Biochars from wood (eucalyptus sawdust, pine bark), sugarcane bagasse, and substances rich in nutrients (coffee husk, chicken manure) produced at 350, 450 and 750°C were characterized to identify agronomic and environmental benefits, which may enhance soil quality. Biochars derived from wood and sugarcane have greater potential for improving C storage in tropical soils due to a higher aromatic character, high C concentration, low H/C ratio, and FTIR spectra features as compared to nutrient-rich biochars. The high ash content associated with alkaline chemical species such as KHCO3 and CaCO3, verified by XRD analysis, made chicken manure and coffee husk biochars potential liming agents for remediating acidic soils. High Ca and K contents in chicken manure and coffee husk biomass can significantly replace conventional sources of K (mostly imported in Brazil) and Ca, suggesting a high agronomic value for these biochars. High-ash biochars, such as chicken manure and coffee husk, produced at low-temperatures (350 and 450°C) exhibited high CEC values, which can be considered as a potential applicable material to increase nutrient retention in soil. Therefore, the agronomic value of the biochars in this study is predominantly regulated by the nutrient richness of the biomass, but an increase in pyrolysis temperature to 750°C can strongly decrease the adsorptive capacities of chicken manure and coffee husk biochars. A diagram of the agronomic potential and environmental benefits is presented, along with some guidelines to relate biochar properties with potential agronomic and environmental uses. Based on biochar properties, research needs are identified and directions for future trials are delineated.

/pdf/properties-of-biochar-derived-from-wood-and-high-nutrient-31ehc3fw8v.pdf

Properties of biochar derived from wood and high-nutrient biomasses with the aim of agronomic and environmental benefits

Preparation and characterization of activated carbon from palm shell by chemical activation with K2CO3.

http://eportfolio.lib.ksu.edu.tw/~4970N007/repository/fetch/Ads.%20CO2%20polyethyleneimine%20AC%20Excellent.pdf

Adsorption capacities of carbon dioxide, oxygen, nitrogen and methane on carbon molecular basket derived from polyethyleneimine impregnation on microporous palm shell activated carbon

Production of carbon molecular sieves from palm shell based activated carbon by pore sizes modification with benzene for methane selective separation

The carbon modified silica adsorbents were prepared by synthesizing and modifying zeolite Y type with activated carbon. This paper reports on effects of activated carbon loadings on the methane and nitrogen adsorption, structure and properties of carbon modified zeolite Y. With the increase in activated carbon loadings, the surface area, pore size and pore volume of the activated carbon loaded zeolite Y adsorbent decreased. The intensity of the diffraction patterns of zeolite Y decreased after the activated carbon was loaded. With increasing activated carbon loadings, the intensity of diffraction peaks decreased. Adsorption capacity of nitrogen (N2) was smaller than adsorption capacity of methane (CH4) by using activated carbon modified silica. When activated carbon loadings 30% wt.%, adsorption capacity of methane and nitrogen was 12.9317 wt.% and 12.6115 wt.%, these were caused by difference in molecular weight. The molecular weight of nitrogen is bigger than molecular weight of methane.

Carbon Modified Silica based Adsorbent for Potential Application

The main objective in this work is study the influence of activation times in the preparation of activated carbon by the method of potassium carbonate (K2CO3)chemical activation. The characteristics and pore development of the prepared activated carbon were investigated. The experiments were carried out with activation time varied from 0.5 to 4.0 h. The results show that in all cases, increasing the activation time the yield decreases, while the adsorption of CO2 will increase, progressively. It was found that the specific surface area of activated was at a maximum value (about 1170 m 2 /g) at a activation time of 2.0 h with carbonization temperature of 800 0 C and at an impregnation ratio of 1.0.

Donni Adinata

Papers

Preparation and characterization of activated carbon from palm shell by chemical activation with K2CO3.

Adsorption capacities of carbon dioxide, oxygen, nitrogen and methane on carbon molecular basket derived from polyethyleneimine impregnation on microporous palm shell activated carbon

Production of carbon molecular sieves from palm shell based activated carbon by pore sizes modification with benzene for methane selective separation

Carbon Modified Silica based Adsorbent for Potential Application

Activated carbon from palm shell, an agricultural waste, using k2co3: influence of activation time on pore development