The Research On The Adsorption Capacity Of Activated Carbon To Acetyl Salicylic Acid And Acetyl Amino Phenol In Water

Water pollution triggers more and more attention from people with continuous growing of word economic level. Pharmaceutical and personal care products(PPCPs) would show characteristics of environmental hormone poisonousness, endocrine disruption, microbial toxicity and biological accumulation to some extents and could not be removed effectively by tradition water treatment technology, which made PPCPs a hot research issue and should be taken seriously. Antipyretic, analgesic and anti-inflammatory drugs as one large class of PPCPs are widely used and take the largest proportion of medicine among people’s common life. Obviously, these drugs stay at a serve residual situation in water environment. In order to decrease the residual amount of these drugs in water environment, activated carbon was used in this article because of its characteristics of stable chemical property, large superficial area, large amount of pores, controllability of pore diameters, renewability, high absorption capacity, low cost and operation simplicity etc. And absorption experiments to aspirin(ASP) and paracetamol(PCTM) in aqueous solution were conducted using dynamic absorption methods with the objective of determining the most appropriate absorption condition and absorption model.Two kinds of activated carbon- maize straw activated carbon and coconut shell activated carbon- were chosen and modified in the experiment. The structural characteristic was represented via Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM) and the relationship between pore structure and functional groups and adsorption capacity were investigated.Maize straw activated carbon and commercial activated carbon were modified by hydrochloric acid and sodium hydroxide,and were used in the absorption experiment to PCTM. It is demonstrated from the experiment results that the balance point was basically reached after 30 minutes absorption process which is in conformity with first order kinetic model and better described using Langmuir equation. It is also found that the process is an endothermic reaction and the absorption effect was more significant using HCL modified activated carbon. Furthermore, the absorption rate of HCL modified maize straw activated carbon was at most 20%, compared with 80% of HCL modified coconut shell activated carbon. The corn maize straw was characterized showing that the specific surface area and pore structure changes a little. And it is only showed through infrared spectra that the oxygen containing functional groups increased, which indicated that the corn straw activated carbon was not suitable for the adsorption of these substances.Coconut shell activated carbon were modified by nitric acid and sodium hydroxide,and were used in the absorption experiment to ASP. It is demonstrated from the experiment results that the absorption process is in conformity with second order kinetic model and better described using Langmuir equation. It is also found that the process is an exothermic reaction and cooling is beneficial to adsorption. Both activated carbons modified by two kinds of materials show good adsorption effect to ASP. Representation shows an increase of oxygen-containing functional groups in modified activated carbon. It is also indicated significant changes happened on SEM, specific surface area, pore size and pore capacity of modified activated carbon.