改性纳米MnO2催化剂对发泡混凝土中H2O2作用效率的影响研究

Study on the effect of nano-MnO2 catalyst modification on the efficiency of H2O2 in foamed concrete

采用水热法制备了4种纳米MnO2催化剂,通过测试催化双氧水分解的速率、水泥的发泡高度研究了纳米MnO2催化剂对化学发泡混凝土中H2O2的作用效率,同时研究了发泡剂掺量和纳米MnO2催化剂对发泡混凝土的干密度、抗压强度等性能的影响。结果表明:以硅藻土为负载物,经过改变制备工艺而制得的纳米MnO2催化剂Cu-MnO2@硅藻土对双氧水分解的催化效果最佳,Cu-MnO2@硅藻土组的发泡高度远高于其他载体的纳米MnO2催化剂,且在制备超轻泡沫混凝土时其干密度可降低40 kg/m3;纳米MnO2催化剂的加入能够在达到相同干表观密度时降低发泡剂的用量,同时抗压强度损失较小,甚至还有小幅提升。

Four nanometer MnO2 catalysts were prepared by hydrothermal method.By measuring the rate of catalytic hydrogen peroxide decomposition and the foaming height of cement,the effect of nano MnO2 catalyst on H2O2 in chemical foamed concrete was studied.Meanwhile,the effects of the amount of foaming agent and nano-MnO2 catalyst on the dry density and compressive strength of foamed concrete were also studied.The results show that the nano-MnO2 catalyst Cu-MnO2@D prepared by changing the preparation process with diatomaceous earth as the load has the best catalytic effect on the decomposition of hydrogen peroxide.The foaming height of the Cu-MnO2@D group is much higher than that of the nano-MnO2 catalyst of other supports,and it can reduce the dry density of 40 kg/m3 when preparing ultra-light foam concrete.The addition of nano-MnO2 catalyst can reduce the amount of foaming agent when the same dry apparent density is reached,while the loss of compressive strength is small,and there is even a slight increase.