Doped boron nitride capable of removing heavy metal in high-temperature flue gas and preparation method thereof

Abstract

The invention provides a doped boron nitride capable of removing heavy metal in high-temperature flue gas. The doped boron nitride comprises, by molar ratio, 0.1-1 mol of a doping substance, 1-5 mol of melamine and 1-5 mol of boric acid, wherein the raw materials of the melamine and boric acid are required for preparation of boron nitride. A preparation method of the doped boron nitride is also provided. The method includes the step of introducing the doping substance during preparation of a first-step precursor on the basis of preparation of the porous boron nitride based on a two-step approach to prepare a porous boron nitride material having a high specific surface area and high porosity, the adsorption selectivity of the heavy metal in the high-temperature flue gas according to different doping substances is different, and the doped boron nitride has higher adsorption capacity for the heavy metal in the high-temperature flue gas than undoped porous boron nitride.

Description

technical field

[0001] The invention provides a doped boron nitride capable of removing heavy metals in high-temperature flue gas, and a preparation method of the doped boron nitride. Background technique

[0002] With the development of China's urban modernization, my country's sewage treatment volume has increased year by year, and sludge as a by-product of sewage treatment has also increased. According to statistics, in 2018, my country's annual sludge output was about 40 million tons (based on a moisture content of 80%), and the treatment rate was less than 30%. The content of heavy metals in my country's sludge is relatively high, and some relatively prominent heavy metals such as Zn can reach several thousand ppm, and the average value can reach 1450 mg / kg. Incineration, as a technical method of sludge disposal with the best effect of "reduction, harmlessness, and resource utilization", has developed rapidly in the world. The "Guidelines for Best Available Technologi...