Along with the more and more use activated alumina in some application. the very important work is to do the activated alumina regeneration by the users. Now we simply say the activated alumina regeneration.
When activated alumina is used for a certain period of time, the adsorption equilibrium is reached. If it is not processed in time, it cannot be used again. From an economic or resource perspective, the regeneration of activated alumina is the best method.
In general, all solid substances have the ability to adsorb, but only porous substances or very finely ground substances can be used as adsorbents because of their large surface area. The adsorbent must also meet the following requirements: strong adsorption capacity; good adsorption selectivity; low adsorption equilibrium concentration; easy regeneration and reuse; good mechanical strength; stable chemical properties; It is difficult for the general adsorbent to meet the requirements of these seven aspects at the same time. Therefore, it should be selected according to different occasions.
ctivated alumina is a hard, aqueous alumina particle. After dehydrated and activated, the hydrous alumina is activated to form a porous structure of solid particles or powder, which can be used as drying of air or gas, concentration and desulfurization of organic hydrocarbons or petroleum gas, refining of coke oven gas or refinery gas, and the like。
The heating regeneration method is the best method for regenerating the activated alumina with saturated activated organic saturated, and is widely used. By externally heating the activated activated alumina, the adsorption equilibrium relationship is changed to achieve the purpose of desorption or decomposition of the absorbed organic material. Activated alumina, commonly used for the adsorption of volatile components, can be desorption and regeneration at lower temperatures. Heat regeneration methods include high temperature heating regeneration method and low temperature heating regeneration method. The high-temperature heating method regenerates the activated activated alumina through drying and activation in a regeneration furnace. Into the regenerative furnace, it is dehydrated and heated to a temperature above 150°C to evaporate the water in the pores of the activated alumina and part of the low-boiling sorbate. The activated alumina particles are gradually dried, and then the active alumina is oxidized under lean conditions. The temperature is raised to about 350 degrees, and desorption and desorption of the adsorbate in the pores of activated alumina are achieved
For activated alumina for water treatment application, how to do actitivated alumina regeneration?
Activated alumina used in modern water purification is a white spherical porous particle. It has uniform particle size, smooth surface, large mechanical strength, strong hygroscopicity, and strong absorption of fluorine. It is mainly used for drinking water in areas with high fluoride. Fluoride removal. However, any product has a service life or service life. Activated alumina is no exception. After long-term use, the activated alumina surface appears yellow-brown, and the effect of defluoridation is reduced. It cannot be reused when it is saturated.
Therefore, the saturation regeneration of activated alumina is very necessary. There are two kinds of regeneration methods for activated alumina. One is to put the activated alumina after saturation into aluminum sulfate solution for 30 hours, and then discard the solution and then use clean water. Wash 3 to 5 times. If there is too much impurity in the solution, it can be treated with 3% hydrochloric acid once and then regenerated by the above method.
Another method is to use dilute nitric acid impregnation and calcination method to regenerate. After it is washed and dried waste activated alumina, the activated alumina is placed in the pool and soaked in 8%-20% dilute nitric acid solution. After 5-25 minutes, the impregnated activated alumina is washed with water and dried. The dried material is placed in a kiln and naturally cooled to room temperature after calcination. The active alumina treated by the method has low processing cost and good product activity has important environmental protection and economic benefits.