Adsorption Of Sulfa Antibiotic By Particles In Conventional Drinking Water Treatment Process

The impact of Pharmaceutical and Personal Care Products on the environment,flora and fauna and human health is concerned by people in recent years andgradually develops into a global hot issue. As a big country in producing and usingPPCPs, the pollution of PPCPs to the water environment of our country should not beignored. Once into the water source, PPCPs will give a serious threat to the safety ofdrinking water. Particle size distribution is extremely extensive in natural waterespecially particles of small grain size, they have bigger specific surface area andstronger adsorption capacity of pollutants in water than which of large grain size. Alarge number of PPCPs can probably be absorbed by micron grade particles in water,then enriched, finally pass through the cell membranes by food chain or other variouschannels and constitute a potential hazard to human health.Sulfamethoxazole and sulfadiazine are typical and frequently-used sulfonamideswhich widely exist in the environment. A trace analysis method by solid phaseextraction high performance liquid chromatography (HPLC) can determine the lowcontent of sulfamethoxazole and sulfadiazine in drinking water. The eluate is100%methanol, the25percent of the mobile phase is0.1%formic acid aqueous solutionand the other75percent is acetonitrile. The flow is0.3ml/min, the injection amount is10μl, the sulfamethoxazole parent ion is254, the proportion of characteristic ions is156/108, the crushing voltage is100v, the collision energy is19v, the recurrence rateof sulfamethoxazole and sulfadiazine reaches90.63%and87.48%respectively.Through the analyses of energy spectrum, scanning electron microscopy andnano particle size instrument to the effluent of conventional water treatment process,the ultimate composition, particle size distribution and other laws of the effluent ofdifferent treatments are observed. In this experiment, the particles in the water aremainly composed of clay minerals. The large particles are better removed by treatingprocesses of coagulation-precipitation-filtration-disinfection, but the removal rate ofsmall particles (d＜1μm) is very low. The turbidity has no relationship with theparticle size. Besides, under natural conditions small particles will aggregate intolarge particles spontaneously.Detecting the number of particles in different size range, the content ofsulfamethoxazole and sulfadiazine and its variation with time in solid phase or liquidphase, the findings prove in the content of sulfamethoxazole and sulfadiazine are very low, but conventional water treatment process almost have no ability to removesulfamethoxazole and sulfadiazine.It found that the particles in water have adsorptioneffect on sulfamethoxazole and sulfadiazine, the adsorbance increases over time. Thiswill jeopardize human health.