A method for removing micro or trace amounts of bromate in water using polymer fibers as carrier-loaded nano-iron

Abstract

The invention discloses method for removing micro or trace bromate from water by using loaded nanometer iron taking high-molecular fiber as a carrier. The method comprises the following steps: adding a polypropylene fiber loaded nanometer zero-valent iron material into a reaction bottle which contains a bromate solution subjected to nitrogen deoxidization treatment, wherein the amount of the loaded zero-valent iron is 6.5mg / g to 33.3mg / g, and the initial concentration of the bromate is 0.5mg / L to 1.5mg / L; sealing the reaction bottle and oscillating the reaction bottle in a constant-temperature water-bath oscillator at a rotating speed of 170rpm at the temperature of 25 DEG C within a pH range of 2.8 to 12.0 for 1-2 hours. The nanometer zero-valent iron loaded on the surfaces of the fibers is high in reducibility and capable of rapidly reducing trace bromate in the water into bromide ions so as to fulfill the aim of removing the bromate from the water. The method has the advantages of low material usage, high removal rate and the like.

Description

technical field [0001] The invention relates to a method for removing micro or trace amounts of bromate in water, which belongs to the water purification treatment process. Background technique [0002] Bromate, a disinfection by-product, is produced after ozone disinfection. Bromate is considered to be a potential carcinogen with genotoxicity. The World Health Organization (WHO), the U.S. Environmental Protection Agency (USEPA) and my country's current "Drinking Water Hygienic Standards" (GB5749-2006) all stipulate that bromine in drinking water The content of bromate should be lower than 10μg / L, and the existing water treatment process cannot meet the national standard of bromate, so it is urgent to treat bromate in drinking water. [0003] At present, the methods of reducing bromate in drinking water are mainly divided into two categories. The first method is to control the formation process of bromate: reduce the pH value, add ammonia, add hydrogen peroxide and other mea...

AI Technical Summary

Problems solved by technology

However, these methods for removing bromate all have deficiencies. After activated carbon is used for a period of time, biofilm will be formed on the surface, reducing the treatment effect; the treatment cost of ion exchange membrane bioreactor is high and high-concentration bromate wastewater will be produced. The pollutants have been transferred, and the purpose of removal cannot be achieved; the reaction time of the biodegradation method is long, and a strong post-treatment process is required to remove the organisms and excess ethanol in the water; the inadequacies of layered double hydroxide Because it cannot be regenerated when it is transformed into a-FeOOH and amorphous aluminum hydroxide; Pd / Al 2 o 3 The disadvantage of the catalytic reduction method is that the catalyst is not easy to recover and may cause secondary pollution in water

The disadvantage of the ultraviolet irradiation method is that it requires a higher energy ultraviolet lamp for irradiation, which increases the processing cost

[0005] Zero-valent iron is divided into three types: zero-valent iron powder, nano-sized zero-valent iron particles and loaded zero-valent iron. Among them, (1) zero-valent iron powder is used to reduce and remove bromate, and dissolved oxygen in water reacts with iron Form passivation film and reduce reduction reaction rate

(2) The structure of nano-zero-valent iron particles has a high specific surface area and surface reactivity, which provides favorable conditions for improving the reduction effect. However, due to the lack of surface protection, the nanoparticles are agglomerated or oxidized to reduce the degradation efficiency, and Nanoparticles are difficult to recover from water leading to secondary pollution

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