A load-type defluorination agent for removing hydrogen fluoride in hydrogen chloride gas and its preparation method

Abstract

The invention discloses a load-type fluorine remover used for removing hydrogen fluoride in hydrogen chloride gas, which is composed of a porous carrier and a fluorine removal active ingredient loaded on the porous carrier, the fluorine removal active ingredient can be existed on inner part and external surface of the tunnel of the porous carrier in a thin layer mode with particles of 0.1nm-5mum, and the mass ratio of the fluorine removal active ingredient to the porous carrier is 0.0005-3: 1. The invention also provides a preparation method of the load-type fluorine remover. The preparation method thereof has the advantage of simple process, and the prepared load-type fluorine remover has the advantages of high utilization rate, good fluorine removal effect and green environmental protection.

Description

technical field [0001] The invention relates to a method for purifying and recovering hydrogen chloride, in particular to a loaded defluorinating agent for removing hydrogen fluoride in hydrogen chloride gas and a preparation method thereof. Background technique [0002] With the rapid development of the fluorine chemical industry, the comprehensive utilization of a large amount of by-product hydrogen chloride gas has become an urgent problem. Due to the presence of hydrogen fluoride in the by-product hydrogen chloride gas, its utilization is greatly restricted. At present, in addition to partial recycling in the production of chlorosulfonic acid, monochloromethane, calcium chloride, barium chloride, etc., most of them are absorbed into fluorine-containing hydrochloric acid for sale. The method is relatively simple, not only the economic benefit is not high, but also the Containing fluorine can pose a potential environmental hazard. Removing hydrogen fluoride from by-produ...

AI Technical Summary

Problems solved by technology

The disadvantage is that the process is cumbersome and can only be applied to the defluorination of HCl gas with low HF content

The disadvantage is that the anhydrous alkaline earth metal chloride particles can be quickly wrapped by the alkaline earth metal fluoride, which is the reaction product of defluorination, resulting in a decrease in utilization rate and defluorination efficiency, and the gas needs to be cooled and adsorbed in multiple stages, which requires a large investment in equipment and energy. high consumption

Similar to US4317805, the disadvantage of this method is that the anhydrous calcium chloride particles can quickly be the reaction product of defluorination, i.e. CaF 2 Wrapped, resulting in a decline in utilization and fluoride removal efficiency

The disadvantage is that it is only suitable for the defluorination of HCl gas with low HF content, and the solution after the reaction is prone to secondary pollution

The disadvantage is that the utilization rate of the adsorbent is low, the fluoride removal efficiency drops rapidly, and the processing capacity is relatively small

The disadvantage of this method is that it cannot directly process HCl gas, but can only process liquefied HCl with low HF content.

[0012] In the above invention patents, in addition to adsorbing and removing fluorine through porous materials such as activated alumina, activated carbon or molecular sieves, non-supported CaCl is mostly used 2 , AlCl 3 , CaO, Ca(OH) 2 Etc. active component particles adsorb and remove fluorine, the active component particle size is large, the porosity is low, and the effective specific surface area is small, so the utilization rate is low

The common defect is that the defluorination efficiency is limited to ppm level, the defluorination capacity is low, and it is mostly suitable for the defluorination of HCl gas with low HF content, or the defluorination process is complicated, which is easy to cause secondary pollution

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