PROCESS FOR PRODUCING 4A ZEOLITE BY TREATING BAYER PROCESS RED MUD WITH ANDRADITE ONE-STEP ALKALI HEAT METHOD

摘要

Provided is a process for producing 4A zeolite by treating Bayer process red mud with an andradite one-step alkali heat method, the process for producing 4A zeolite comprising the following steps, S1: mixing red mud, an iron-rich material, active lime and a circulating mother liquor to prepare a raw material ore slurry; S2: subjecting the raw material ore slurry to an alkali thermal dissolution reaction to obtain a dissolved ore slurry; S3: diluting the dissolved ore slurry to obtain a diluent, and subjecting the diluent to liquid-solid separation to obtain a dissolved slag and a dissolved solution, wherein the dissolved solution is a sodium aluminate solution; S4: mixing the sodium aluminate solution with a sodium silicate solution and then adding a crystal form directing agent for a crystallization reaction and solid-liquid separation to obtain 4A zeolite and a sodium aluminate solution with a high molecular ratio; and S5: formulating the sodium aluminate solution with a high molecular ratio to prepare the circulating mother liquor used in step S1. The process recovers alumina and sodium oxide in red mud, reduces the alkali content in the dissolved slag to less than 0.5%, and prepares a 4A zeolite product, the market demand for which is large and which has a high added value, thereby realizing the high value-added utilization of solid waste, and achieving the effect of the green utilization of resources.