Çay atığından adsorbent üretimi ve üretilen adsorbentin adsorpsiyon özelliklerinin incelenmesi
Özet
In this investigation, for the first time, a porous solid with high specific surface area (> 1000 m2/g) was produced from waste tea which is an abundant agricultural by-product in our country. The adsorption capacity of the porous solid prepared and the raw material were determined toward phenol at two different temperatures (15 °C and 30 °C) and also the thermodynamics study of adsorption processes was carried out.The porous solid was prepared primarily with conventional method. K2CO3, which is not a hazardous chemical and not deleterious as it is frequently used for food additives, was used as chemical activation reagent. The milled waste tea which has two different particle size (-500 µm and +500 µm) was used in this study. The effect of production procedures (chemical activation, only carbonisation), concentration of K2CO3 solutions (2.81, 5.63, 8.43, 11.21 M), impregnation ratios (0.5, 1.0, 1.5, 2.0), chemical activation times (0 h, 24 h), carbonisation temperatures (400, 500, 600, 700, 800, 900 °C) and carbonisation times (30, 60, 120 min) on properties of the product (i.e., surface area, pore size distribution, density) were investigated.A novel method was also applied to prepare porous material as well as conventional method. In this new method microwave pretreatment was integrated into conventional method. The effect of water content (9.0, 18.0, 27.0 g), microwave treatment period (120, 150 s) and the use of microwave receptor were investigated on surface area and porosity of the final product.The results showed that chemical activation had an important role to obtain porous material with high surface area and porosity. Impregnation ratio and chemical activation time particularly modified the pore structure. Carbonisation temperature and carbonisation time affected the surface properties and yield of the product. Microwave pretreatment did not have any significant effect on surface properties of the product. On the contrary, by reducing chemical activation time, it saved energy and time of process.The adsorption capacity of the waste tea increased with increasing temperature. The porous material has excellent adsorption capacity for phenol removal, therefore it is suggested that it is effective adsorbent to remove phenol from water.