Fe3O4改性水热炭活化过硫酸钠降解罗丹明B

通过微波水热法，以沼渣为原料，合成了Fe₃O₄改性微波水热炭，研究了Fe₃O₄掺杂量对水热反应进程及反应产物的影响。为拓展水热产物的应用范围，以罗丹明B（RhB）为对象，评价改性水热炭对过硫酸钠的活化能力。结果表明，微波加热功率为400W、Fe₃O₄制备量为水热炭质量的20%时，反应体系14min左右即达到设定温度（200℃），较无Fe₃O₄条件下反应时间（27min左右）缩短了48.1%，体系压强增加了27.8%。改性水热炭添加量为0.16g、反应时间140min、溶液初始pH为6.7、过硫酸钠投加量为0.1g时，体积为150mL、浓度为40mg/L的RhB降解率可达94.6%，是水热炭单独作用时的3.3倍，过硫酸钠单独作用时的3.9倍。在反应体系中以硫酸根自由基（?\mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{2}-}）的作用为主，羟基自由基（·OH）和超氧负离子（?{\mathrm{O}}_{\mathrm{2}}^{-}）为辅。改性水热炭具有良好的超顺磁性和稳定性。

Degradation of Rhodamine B by sodium persulfate activated with Fe3O4 modified hydrochar

Fe₃O₄ modified microwave hydrochar was synthesized from biogas residue by microwave hydrothermal method. The effects of Fe₃O₄ doping amount on hydrothermal reaction process and reaction products were studied. In order to expand the application scope of hydrothermal products, RhB was used as an object to evaluate the activation ability of modified hydrothermal charcoal on sodium persulfate. The results showed that when the microwave heating power is 400W and the amount of Fe₃O₄ produced is 20% of the mass of hydrochar, the reaction system reaches the set temperature (200℃) in about 14 minutes, the reaction time was reduced by 48.1% (about 27min) without Fe₃O₄, the system pressure increased by 27.8%. When the dosage of modified hydrochar is 0.16g, reaction time is 140 min, initial pH of solution is 6.7 and sodium persulfate is 0.1g, the degradation rate of RhB with volume of 150mL and concentration of 40mg/L can reach 94.6%, which is 3.3 times of hydrochar alone, 3.9 times of sodium persulfate alone. In the reaction system, sulfate radical (?\mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{2}-}) was the main active species, and hydroxyl radical (·OH) and superoxide anion (?{\mathrm{O}}_{\mathrm{2}}^{-}) were supplemented. Modified hydrochar has good superparamagnetism and stability.