This is the 14479th most frequent Russian word.
очищенные
"Пeeled" or "purified."
The word "очищенные" is used here as an adjective to describe the nuts, indicating they have been peeled or shelled.
Она купила очищенные орехи в магазине.
She bought shelled nuts in the store.
In this sentence, "очищенные" describes the walls, suggesting they have been cleaned or stripped, indicating an action completed to achieve a cleaned state.
После ремонта необходимо убрать очищенные стены.
After the renovation, it is necessary to clean the walls that have been stripped of their old paint.
Here, "очищенные" modifies the sand within the context of having undergone a purification or refinement process.