Natural-zeolite purification by a sacrificial scavenger porous layer

Modification of natural zeolites and their applications for heavy metal removal from polluted environments: Challenges, recent advances, and perspectives

“…However, like other natural materials, they can incorporate several compensating ions that can bargain their properties and limit their use. The natural zeolites contain impurities such as Fe 2+ , SO 4 2− , quartz, other zeolites, clay minerals, feldspars and amorphous glass, which diminishes the content of valuable components in mineral materials and restrict their commercial applications where purity and uniformity are critical [ 99 , 100 ]. Therefore, single or combined thermal, chemical, modification with surfactant and other modification treatments of natural zeolites ( Fig.…”

“…In this regard, Kukobat et al [ 122 ] reported that water evaporation from natural zeolite up to 200 °C leads to a growth in the specific surface areas, while extra growth in temperature leads to lower porosity. Medfai et al [ 99 ] presented a methodology for purifying natural zeolites by combining heat treatment at 350 °C and acid treatment.…”