The decline in the number of visitors to the National Museum of Indonesia due to the Covid-19 pandemic has had an impact on the room temperature, which can affect the durability of the historical objects belonging to the Museum, which was built on April 22, 1778.
Dr. Yuni Krisyuningsih Krisnandi, M.Sc., a chemistry expert from the Faculty of Mathematics and Natural Sciences, University of Indonesia, and a resource person in a webinar entitled "Prevention is Good - Collection Preservation Strategy During the Pandemic" held online by the National Museum of Indonesia on Tuesday (25/8/2020) discussed the right chemical substances as desiccants for caring for and preserving collections at the National Museum of Indonesia.
The chemical substance in question is Bentonite and ZeoliteDr. Yuni claims that both substances are resistant to high temperatures, allowing them to maintain dry conditions in their surroundings. Furthermore, both natural ingredients are considered environmentally friendly.
So far, the National Museum of Indonesia has used Silica Gel desiccant or absorbent chemical to preserve his collection of objects.
Dr. Yuni explained that a desiccant is a substance that can absorb water vapor from the air, thus effectively controlling humidity. Silica gel, commonly found in shoe packaging, electronics, medicines, and other products, can prevent excessive moisture buildup due to its large surface area.
"Whenever we buy new shoes or cameras, there's usually silica gel, but it's still wrapped. If we open it, each particle can absorb a lot of water vapor because it has a large surface area," said Dr. Yuni.
After absorbing water, Dr. Yuni continued, silica gel can also change color. For example, blue silica gel or clear silica gel with added cobalt. If the blue silica gel has absorbed a large amount of water vapor on its surface, it will change color to pink.
"These changes are due to a chemical reaction between cobalt and H2O or water vapor that accumulates on the surface of the gel cilia," added Dr. Yuni.
According to Dr. Yuni, each museum collection item has a different humidity sensitivity, which influences the type and quantity of silica gel used. The higher the absorbency, the higher the cost for large-scale use.
The silica gel that is commonly used can be reused (reactivated) with the right procedure, however, it will have a negative effect if the silica gel is thrown away because silica gel contains heavy metals.
That is the background to Dr. Yuni offering innovation. Bentonite and Zeolite as an alternative chemical to preserve museum collections.
Besides being resistant to high temperatures, bentonite is also claimed to be safe to use because this clay mineral is part of the silicate family with a stacked leaf structure and can bind water and is non-toxic.
Meanwhile, zeolite minerals are a family of silicates with a building-like structure because of their three-dimensional shape.
Zeolite is also often referred to as a 'molecular sieve' / 'molecular mesh' because zeolite has molecular-sized pores so it is able to separate / filter molecules of a certain size.
Bentonite and Zeolite can be suitable alternative substances if these two natural materials are modified.
Dr. Yuni stated that bentonite and zeolite are abundant in Indonesia, making them easy to find and produce in large quantities. However, she acknowledged that processing these two substances is not easy.
So he suggested that the Indonesian National Museum could collaborate with Bentonite and Zeolite mining companies.
"Because the treatment itself is quite complicated, the National Museum can collaborate with Zeolite and Bentonite Mining Entrepreneurs to provide the materials according to the Museum's needs," said Dr. Yuni at the end of her presentation.
