Preprocessing method for removing nanoscale iron-bearing substance Kelvin balance disturbance

Abstract

Provided is a preprocessing method for removing nanoscale iron-bearing substance Kelvin balance disturbance. When adsorbent or catalyst with a nanoscale iron-bearing substance adopted carries out measurement on organic content after carrying out adsorbing or catalyzing, due to the fact that iron-bearing colloid of Kelvin equilibrium dissolution enables to-be-measured liquid to present red color, absorption is produced, and measurement on organics by ultraviolet spectrophotometry, gas phrase or liquid phrase color spectrum is disturbed. After a pH value of the to-be-measured liquid is measured, iron-bearing salt is adopted to neutralize electric charge carried by the iron-bearing colloid, a high speed centrifuge of 4000 rpm / min is adopted, after liquid-solid separation is finished, the pH value is modulated back, the solution is sent to be measured, disturbance of the iron-bearing colloid on the measurement is removed, and aluminum saltalum floc does not produce adsorption on the organics and also not change original adsorption of the iron-bearing colloid. The preprocessing method for removing the nanoscale iron-bearing substance Kelvin balance disturbance is easy and convenient to achieve, low in cost, small in error and convenient to operate, and the situations that the measurement on the organics by ultraviolet the spectrophotometry, the gas phrase or the liquid phrase color spectrum is disturbed by the iron-bearing adsorbent or the catalyst Kelvin balance are avoided.

Description

technical field [0001] The invention relates to a pretreatment method for eliminating kevin equilibrium interference of nanoscale iron-containing substances during content determination after adsorption or catalysis of organic substances. Background technique [0002] Nanoscale iron-containing substances (including iron oxides and iron hydroxides) are mostly semiconductors, which have excellent quantum effects, low price, good environmental compatibility, and large adsorption capacity. The band gap is 2.0~2.3eV. It has photocatalytic activity under the action of sunlight, and is widely used as an adsorption material or photocatalytic material, such as: 1. Patent No. CN200910071515, title of invention: method for treating organic wastewater with ferrite as an adsorbent. 2. Patent No.: CN201010237605.4 Invention Name: A preparation method of bismuth ferrite photocatalyst. [0003] During the adsorption and catalysis of organic matter by nano-iron-containing substances, due to...

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Problems solved by technology

[0003] During the adsorption and catalysis of organic matter by nano-iron-containing substances, due to the small particle size of nano-minerals, generally 2-200nm, they have great surface energy. Due to kelvin’s equation in wastewater, the solubility change is ln(S 常规 / S 超细 )=2δ sl M÷(RTργ), at 20°C, when the pH is 7, when the radius of curvature of iron minerals changes in the range of 1-100nm, Fe 3+ The solubility of iron ions increases to 18.67-2.75 times that of non-nano-scale substances. The excessive solubility of iron ions makes the wastewater after adsorption and catalytic treatment show a certain color. The wastewater after adsorption and catalytic unit operation adopts ultraviolet-visible spectroscopy When photometer, gas phase or liquid chromatography are used to analyze the content of organic matter, due to the existence of iron colloids, it will seriously interfere with the measurement results and often lead to false conclusions that the concentration of organic matter in wastewater after adsorption and catalytic unit operation increases instead

Common microfiltration membranes and ultrafiltration pretreatment methods cannot remove dissolved iron colloids. When using solid phase extraction, due to the super adsorption capacity of dissolved iron colloids on the surface of organic matter, it is still impossible to accurately determine the content of organic matter in wastewater.

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