Production method of red mud modified by Fred's salt as heavy metal flocculation-adsorbent

Abstract

The invention discloses a production method of Friedel's salt modified red mud used as a heavy metal flocculant-adsorbent, and the mass ratio between the solid state red mud which is grinded into fine powder and a Frieders salt emulsion which contains Calcium and Aluminum whose mol ratio is 4:1 is 1:(0.2-0.9), and the red mud and theFriedel's salt emulsion are placed in a reactor and are mixed with water,and are subjected to intense stirring and mixing for reaction in a condition with normal temperature, normal pressure, apH value higher than 10 and a watersolid ratio which is 1-4:1, a mixture is obtained after continuous stirring lasting for 0.5-1.5 hours.The mixture ispermitted to stand for curing for more than or equal to 20 hours, solidsand a clarified liquid are separated, the sodium-freeFriedel's salt modified red mud with micro-nanoneedle-like and layer-like structures wrapped each other is obtained, and the modified red mud can be used as the heavy metal flocculation-adsorbent. The invention has the advantages of energy conservation and consumption reduction, low equipment corrosion, simple process, low cost and 'zero three waste (waste gas, waste water and industrial residue)'discharge, etc. The product provided by the invention is used for restoration of soil which is polluted by heavy metal, and effective deep purification of electroplating waste water and metal recovery waste water.

Description

technical field [0001] The invention relates to a production method of using Fred's salt modified red mud as a heavy metal flocculation-adsorbent, and belongs to the technical field of red mud utilization and production of water purifiers and heavy metal polluted soil remediation agents. Background technique [0002] Red mud is solid waste slag discharged during the alumina production process. It is highly alkaline and polluting waste slag. It is called red mud because it contains a large amount of iron oxide and turns red. As the world's fourth largest producer of alumina, China discharges millions of tons of red mud every year. Due to the difference in ore grade, production method and technical level, about 0.3-2.5t of red mud is discharged for every ton of alumina produced. As the grade of bauxite decreases year by year, the discharge of red mud for the production of ton of alumina also increases year by year. . [0003] The chemical composition of red mud is shown in T...

AI Technical Summary

Problems solved by technology

The technical solutions of these patents mainly have major problems such as long process, high energy consumption, and incomplete utilization of resources; while other public red mud modification reports in the prior art only involve changes in its surface properties, which are difficult to meet practical applications. requirements

Therefore, the existing disclosed methods of using red mud as a raw material to modify and produce sewage purifiers or as soil remediation agents are not ideal enough and cannot meet the needs of use.

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