Detecting method of free aluminum in aluminium polychlorid

Abstract

The invention discloses a detecting method of free aluminum in aluminium polychlorid. The method comprises the following steps that S1, weighing is conducted, specifically, 8-10g of a liquid aluminiumpolychlorid sample is weighed, attenuation is conducted by water to obtain aluminium polychlorid liquid, aluminium polychlorid liquid with quantitative volume is taken, excessive sodium ethylene diamine tetracetate standard solution is added and is adjusted to a solution with PH being about 4.5-5.5 by ammonium hydroxide solution; S2, heating and cooling are conducted, specifically, the solution with well adjusted PH value in the S1 is positioned at an electric stove to be heated to 80-90DEG C and lasts 5-6min, and then the solution is taken from the stove to be cooled to the indoor temperature; and S3, calculating is conducted, about10ml of a buffer solution with PH being 5.5-6 is added into the cooled solution in the S2, and 2-3 drops of xylenol orange indicator are added. Through detection of the free aluminum, effective reference is provided for production control. The detecting method is simple, and aluminium polychlorid sample can be conveniently recycled and processed after detection, and environment pollution is avoided.

Description

technical field [0001] The invention relates to the technical field of polyaluminum chloride production, in particular to a method for detecting free aluminum in polyaluminum chloride. Background technique [0002] Polyaluminum chloride is a new water purification material, inorganic polymer coagulant, referred to as polyaluminum, English abbreviation is PAC (poly aluminum chloride), it is between AlCI3 and Al(OH)3, a kind of Water-soluble inorganic high molecular polymer, the general chemical formula is [Al2(OH)nCl6-nLm], where m represents the degree of polymerization, n represents the degree of neutrality of PAC products, and n=1-5 is a highly charged polymerization with Keggin structure The ring chain body has a high degree of neutralization and bridging effect on colloids and particles in water, and can strongly remove micro-toxic substances and heavy metal ions. It has stable properties. Due to the bridging effect of hydroxide ions and the polymerization of polyvalent ...

AI Technical Summary

Problems solved by technology

[0002] Polyaluminum chloride is a new water purification material, inorganic polymer coagulant, referred to as polyaluminum, English abbreviation is PAC (poly aluminum chloride), it is between AlCI3 and Al(OH)3, a kind of Water-soluble inorganic high molecular polymer, the general chemical formula is [Al2(OH)nCl6-nLm], where m represents the degree of polymerization, n represents the degree of neutrality of PAC products, and n=1-5 is a highly charged polymerization with Keggin structure The ring chain body has a high degree of neutralization and bridging effect on colloids and particles in water, and can strongly remove micro-toxic substances and heavy metal ions. It has stable properties. Due to the bridging effect of hydroxide ions and the polymerization of polyvalent anions, The produced polyaluminum chloride is an inorganic polymer water treatment agent with relatively large molecular weight and high charge. Polyaluminum chloride has good spray drying stability, wide water area, fast hydrolysis speed, strong adsorption capacity, and the formation of alum Large flowers, dense quality and fast precipitation, low turbidity of effluent, good dehydration performance, etc. In the production process of polyaluminum chloride, the basicity of polyaluminum chloride is a relatively important index in polyaluminum, especially for drinking water level For polyaluminum products, usually only the total aluminum content in the material is detected. The sample is depolymerized by adding nitric acid, and the excess EDTA is back-dropped with zinc chloride standard solution to precipitate the aluminum content. The defect of this method is that the polymerized aluminum and the free aluminum Testing together does not really reflect the degree of polymerization of the product, which leads to the phenomenon that the product has an unstable use effect even though the aluminum content reaches the standard