t改性竹蔗渣生物炭对水中阿莫西林的去除性能研究

Unmodified (BBAC) and phosphoric acid-modified biochar (P-BBAC) were prepared at 250°C, 450°C and 650°C using Fujian's characteristic century-old sugarcane waste (bamboo bagasse), respectively, and used to remove Amoxicillin (AMX) in water. Through the preliminary adsorption test, the optimal adsorbent P-BBAC 650 was screened out (preparation conditions were immersion bagasse: phosphoric acid ratio 1:1.16, pyrolysis temperature 650 ℃ and pyrolysis time 60 min). Subsequently, the effects of adsorption time, solution pH, dosage, initial concentration and temperature on the performance of P-BBAC 650 adsorption solution for AMX were systematically explored. Select pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetic models to fit the adsorption process, and use Langmuir and Freundlich equations to fit the isotherm adsorption process, combined with specific surface area test (BET), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and Fourier transform infrared spectroscopy (FTIR) and other characterization methods were used to analyze the structural changes and adsorption characteristics of biochar. The results showed that under the conditions of natural pH and room temperature (25 ℃), using 1.33 g/L P-BBAC 650 to adsorb 50 mg/L AMX, the adsorption equilibrium could be reached within 60 min, and the AMX removal efficiency was as high as 96.0%. The adsorption process of AMX conforms to the pseudo-second-order kinetic model, and the adsorption isotherm conforms to the Langmuir and Freundlich isotherm equations. The theoretical maximum adsorption capacity of Langmuir is as high as 198.8 mg/g at 65 °C. The adsorption thermodynamic results indicated that the adsorption was a spontaneous, endothermic and entropy-increasing adsorption process. The results of characterization analysis and pH effect prove that P-BBAC 650 has more good adsorption sites for AMX, and has successfully adsorbed amoxicillin on its surface. The adsorption mechanism is mainly the interaction of electrostatic and hydrogen bonds. Therefore, P-BBAC 650 can be used as a highly efficient adsorbent for the removal of AMX antibiotics from water. reductionaverage pore size of 4.72 nm and excellent morphological properties for efficient removal of AMX, the main mechanisms of AMX adsorption on P-BBAC650 would be electrostatic attraction and hydrogen bonding. Therefore, biochar P-BBAC650 may be used as a promising adsorbent of antibiotics in contaminated waters.