Step one

Mix the alginate powder with hot water above 90°C and stir well, let it stand for 24 hours and keep moisture to reduce lumping, so that it forms a uniform gel-like substance.

Step two

Mix the oyster shell powder with sodium alginate gel well.

Step three

Knead the mixture into a dough to form a dough-like texture.

Step four

Pour the mixture into the mold and squeeze the mold to expel as much air as possible from the mold.

Step five

Unmold them carefully after 24 hours.

Step six

Place the demolded samples into a blast drying oven and dry below 35°C for more than 24 hours, paying attention to turning during this time to ensure that the moisture is thoroughly dried.

Step seven

Prepare 2% calcium chloride solution: mix anhydrous calcium chloride and pure water in a beaker according to the ratio, stir well

Step eight

Put the moisture completely dried oyster shell-sodium alginate composite clay sheet into the solution and submerge it completely for about 1 hour

Step nine

Put the moisture completely dried oyster shell-sodium alginate composite clay sample into the solution and submerge it completely for about 1 hour

Step ten

Take the sample out of the solution and put it into a blast drying oven and dry it below 35°C for more than 24 hours until the moisture is completely dry