Activated carbon production from olive stone

Activated carbon is the last product obtained from the activation of carbon-containing materials and contains 72-90% carbon. Activated carbons are useful products that are harmless to human health and have a very high porosity and internal surface area. Active carbon is used as adsorbent and catalyst or catalyst support material in purification or separation of liquids and gases. Additionally, there have been studies done to reduce the effect of global warming by using the active carbon produced from lignocellulosic biomass in place of fossil fuels like coal. Activated carbon is defined by its properties as well as by its source, and it can be produced from almost any organic substance with high carbon content. The physical properties and the chemical composition of the precursor, as well as the methods and process conditions employed for activation, determine the final pore size distribution and the adsorption properties of the activated carbon. In general inexpensive carbonaceous materials are prefered as starting materials for the production of activated carbon Olive is the most produced fruit in the worldwide and it is very common in Mediterranean countries. Maximum production is in the Middle East and Mediterranean countries. 99% of total olive production is occurring in this region. Turkey takes 2nd place after Spain in the production of table olives, and takes 1st place in consumption. In Turkey, olive stone is produced more than 350 thousand tons per year, but olive stone is used as a fuel for much cheaper prices. The transformation of olive stone to activated carbon and using it in the elimination of dyes from waste water instead of using olive as fuel will help IX both to protect environment and to provide a very consumed adsorbent from domestic sources. This also will make a significant contribution to the country's economy. Olive stone is a lignocellulosic material that is composed of hemicellulos, cellos and lignin and it is suitable to produce active carbon. The fact that the high adsorption capacity and durability of the obtained activated carbon provide advantageous in terms of its usage for environmental protection in the future. The olive stone which remains as waste after processing olive which is a very important industrial product in our country is a valuable biomass source. In the presented study, the aim is to produce active carbon from olive stone obtained from fresh olives prepared for breakfast. ZnCl2 and K2CO3 were used as chemical agents in the study. The activation process was carried out in a horizontal fixed bed system and in a nitrogen atmosphere. The effect of the production method on the structural properties of the activated carbon was investigated. Active carbon was characterized by elemental analysis, proximate analysis, heat value, BET, SEM, FTIR and TGA techniques. In addition, a methylene blue adsorption capacity of prepared activated carbons was investigated. The effect of different parameters such as temperature, pH and adsorbed dose on adsorption efficiency was determined. It was determined that the carbon content and the higher heat values of the samples increased after the activation process. It was observed that there was a significant difference in the surface topography of the raw sample and active activated carbons. Porous structure was found in active carbon produced by different methods It was determined that the activation method affected the product yield and properties. BET surface area (747.35 m2/g) and activation efficiency (31.25%) of olive stone activated by ZnCl2 was determined to be high. It was found that the BET surface area of the K2CO3-activated sample increased while the product yield decreased. It was also found that the activated carbon produced by ZnCl2 impregnating has a more porous structure. The highest adsorption efficiency was obtained on the activated sample by ZnCl2. The adsorption capacity of methylene blue of active carbon prepared with ZnCl2 was determined as 98%. As a result, it has been found that using ZnCl2 under suitable conditions, it is possible to produce activated carbon with high quality and efficiency from olive stone. Key words: Activated carbon, olive stone, ZnCl2, K2CO3, adsorption.