Diclofenac(DCF)is one of the most frequently detected pharmaceuticals in groundwater,posing a great threat to the environment and human health due to its toxicity.To mitigate the DCF contamination,experiments on DCF d...Diclofenac(DCF)is one of the most frequently detected pharmaceuticals in groundwater,posing a great threat to the environment and human health due to its toxicity.To mitigate the DCF contamination,experiments on DCF degradation by the combined process of zero-valent iron nanoparticles(nZVI)and nano calcium peroxide(nCaO_(2))were performed.A batch experiment was conducted to examine the influence of the adding dosages of both nZVI and nCaO_(2)nanoparticles and pH value on the DCF removal.In the meantime,the continuous-flow experiment was done to explore the sustainability of the DCF degradation by jointly adding nZVI/nCaO_(2)nanoparticles in the reaction system.The results show that the nZVI/nCaO_(2)can effectively remove the DCF in the batch test with only 0.05 g/L nZVI and 0.2 g/L nCaO_(2)added,resulting in a removal rate of greater than 90%in a 2-hour reaction with an initial pH of 5.The degradation rate of DCF was positively correlated with the dosage of nCaO_(2),and negatively correlated with both nZVI dosage and the initial pH value.The order of significance of the three factors is identified as pH value>nZVI dosage>nCaO_(2)dosage.In the continuous-flow reaction system,the DCF removal rates remained above 75%within 150 minutes at the pH of 5,with the applied dosages of 0.5 g/L for nZVI and 1.0 g/L for nCaO_(2).These results provide a theoretical basis for the nZVI/nCaO_(2)application to remove DCF in groundwater.展开更多
The simultaneous CO_(2) capture and heat storage performances of the modified carbide slag with byproduct of biodiesel were investigated in the process coupled calcium looping and CaO/Ca(OH)2 thermochemical heat stora...The simultaneous CO_(2) capture and heat storage performances of the modified carbide slag with byproduct of biodiesel were investigated in the process coupled calcium looping and CaO/Ca(OH)2 thermochemical heat storage using air as the heat transfer fluid.The modified carbide slag with by-product of biodiesel exhibits superior CO_(2) capture and heat storage capacities in the coupled calcium looping and heat storage cycles.The hydration conversion and heat storage density of the modified carbide slag after 30 heat storage cycles are 0.65 mol·mol^(-1) and 1.14 GJ·t^(-1),respectively,which are 1.6 times as high as those of calcined carbide slag.The negative effect of CO_(2) in air as the heat storage fluid on the heat storage capacity of the modified carbide slag is overcome by introducing CO_(2) capture cycles.In addition,the CO_(2) capture reactivity of the modified carbide slag after the multiple calcium looping cycles is enhanced by the introduction of heat storage cycles.By introducing 10 heat storage cycles after the 10th and 15th CO_(2) capture cycles,the CO_(2) capture capacities of the modified carbide slag are subsequently improved by 32%and 43%,respectively.The porous and loose structure of modified carbide slag reduces the diffusion resistances of CO_(2) and steam in the material in the coupled process.The formed CaCO_(3)in the modified carbide slag as a result of air as the heat transfer fluid in heat storage cycles decomposes to regenerate CaO in calcium looping cycles,which improves heat storage capacity.Therefore,the modified carbide slag with by-product of biodiesel seems promising in the coupled calcium looping and CaO/Ca(OH)_(2) heat storage cycles.展开更多
为改善高钙粉煤灰在混凝土中的体积安定性和水化活性,本文对高钙粉煤灰进行了CO_(2)矿化改性,研究了不同CO_(2)矿化反应时长下高钙粉煤灰的固碳量和游离氧化钙含量,及CO_(2)矿化改性高钙粉煤灰对水泥砂浆水化热、力学性能和孔隙结构的...为改善高钙粉煤灰在混凝土中的体积安定性和水化活性,本文对高钙粉煤灰进行了CO_(2)矿化改性,研究了不同CO_(2)矿化反应时长下高钙粉煤灰的固碳量和游离氧化钙含量,及CO_(2)矿化改性高钙粉煤灰对水泥砂浆水化热、力学性能和孔隙结构的影响。结果表明,经12 h CO_(2)矿化改性处理,高钙粉煤灰固碳量可超过10%(质量分数),高钙粉煤灰中的游离氧化钙含量明显降低。随着矿化反应时间的延长,掺高钙粉煤灰的水泥浆体水化诱导期缩短,早期水化放热量明显降低。CO_(2)矿化改性处理还能减轻高钙粉煤灰对水泥砂浆强度的负面影响,改善水泥砂浆孔隙结构,降低孔隙率和大孔含量,促进水泥的早期水化和水化硅酸钙的成核结晶。展开更多
基金the National Natural Science Foundation of China(42077176,41601514)Shanghai“Science and Technology Innovation Action Plan”Project(19230742400,19ZR1459300)+1 种基金Shanghai Peak Discipline Project(0200121005/053,2019010202)State Key Laboratory of Petroleum Pollution Control(PPC2016019)。
文摘Diclofenac(DCF)is one of the most frequently detected pharmaceuticals in groundwater,posing a great threat to the environment and human health due to its toxicity.To mitigate the DCF contamination,experiments on DCF degradation by the combined process of zero-valent iron nanoparticles(nZVI)and nano calcium peroxide(nCaO_(2))were performed.A batch experiment was conducted to examine the influence of the adding dosages of both nZVI and nCaO_(2)nanoparticles and pH value on the DCF removal.In the meantime,the continuous-flow experiment was done to explore the sustainability of the DCF degradation by jointly adding nZVI/nCaO_(2)nanoparticles in the reaction system.The results show that the nZVI/nCaO_(2)can effectively remove the DCF in the batch test with only 0.05 g/L nZVI and 0.2 g/L nCaO_(2)added,resulting in a removal rate of greater than 90%in a 2-hour reaction with an initial pH of 5.The degradation rate of DCF was positively correlated with the dosage of nCaO_(2),and negatively correlated with both nZVI dosage and the initial pH value.The order of significance of the three factors is identified as pH value>nZVI dosage>nCaO_(2)dosage.In the continuous-flow reaction system,the DCF removal rates remained above 75%within 150 minutes at the pH of 5,with the applied dosages of 0.5 g/L for nZVI and 1.0 g/L for nCaO_(2).These results provide a theoretical basis for the nZVI/nCaO_(2)application to remove DCF in groundwater.
基金supported by the National Natural Science Foun-dation of China(51876105)the Fundamental Research Funds of Shandong University(2018JC039).
文摘The simultaneous CO_(2) capture and heat storage performances of the modified carbide slag with byproduct of biodiesel were investigated in the process coupled calcium looping and CaO/Ca(OH)2 thermochemical heat storage using air as the heat transfer fluid.The modified carbide slag with by-product of biodiesel exhibits superior CO_(2) capture and heat storage capacities in the coupled calcium looping and heat storage cycles.The hydration conversion and heat storage density of the modified carbide slag after 30 heat storage cycles are 0.65 mol·mol^(-1) and 1.14 GJ·t^(-1),respectively,which are 1.6 times as high as those of calcined carbide slag.The negative effect of CO_(2) in air as the heat storage fluid on the heat storage capacity of the modified carbide slag is overcome by introducing CO_(2) capture cycles.In addition,the CO_(2) capture reactivity of the modified carbide slag after the multiple calcium looping cycles is enhanced by the introduction of heat storage cycles.By introducing 10 heat storage cycles after the 10th and 15th CO_(2) capture cycles,the CO_(2) capture capacities of the modified carbide slag are subsequently improved by 32%and 43%,respectively.The porous and loose structure of modified carbide slag reduces the diffusion resistances of CO_(2) and steam in the material in the coupled process.The formed CaCO_(3)in the modified carbide slag as a result of air as the heat transfer fluid in heat storage cycles decomposes to regenerate CaO in calcium looping cycles,which improves heat storage capacity.Therefore,the modified carbide slag with by-product of biodiesel seems promising in the coupled calcium looping and CaO/Ca(OH)_(2) heat storage cycles.
文摘为改善高钙粉煤灰在混凝土中的体积安定性和水化活性,本文对高钙粉煤灰进行了CO_(2)矿化改性,研究了不同CO_(2)矿化反应时长下高钙粉煤灰的固碳量和游离氧化钙含量,及CO_(2)矿化改性高钙粉煤灰对水泥砂浆水化热、力学性能和孔隙结构的影响。结果表明,经12 h CO_(2)矿化改性处理,高钙粉煤灰固碳量可超过10%(质量分数),高钙粉煤灰中的游离氧化钙含量明显降低。随着矿化反应时间的延长,掺高钙粉煤灰的水泥浆体水化诱导期缩短,早期水化放热量明显降低。CO_(2)矿化改性处理还能减轻高钙粉煤灰对水泥砂浆强度的负面影响,改善水泥砂浆孔隙结构,降低孔隙率和大孔含量,促进水泥的早期水化和水化硅酸钙的成核结晶。
