UNAIR NEWS – Chromium (Cr) is one of the most toxic and carcinogenic inorganic pollutants, especially chromium (VI). Chromium (VI) is produced by industrial activities, such as the leather tanning, photography, electroplating, textiles, and dyes industries.
“In small amount, chromium are needed by humans, as a stamina booster medicine for daily activities,” said the FST UNAIR lecturer, Dr. rer. nat. Ganden Supriyanto, Dipl. EST., M.Sc.
Company workers involved in chromium coating process have high-risk to be affected by chromium pollution. The accumulation of steam that is inhaled during the chromium coating process can cause shortness of breath and lead to lung cancer.
Furthermore, the skin exposed continuously to chromium will cause ulceration, ulceration of the mucous membranes of the nose, vascular effect (damaged blood vessels in the aorta), anemia and lethargic body, poor body immunity, reproductive disorders, and kidney disorders.
Therefore, an easy, inexpensive, and effective method to reduce/eliminate chromium from water is needed. For example, through the ion exchange process, separation process with membranes and adsorption.
The adsorption method is the most often used method to remove chromium from water because it is very efficient and economical. Various types of adsorbents have been used to adsorb chromium. Conventional adsorbents such as activated carbon, chitosan, zeolite, and clay mostly used, but the adsorption capacity of the adsorbents are still less selective for heavy metals.
Among the four adsorbents, zeolite is a material that has a very regular crystalline form with interconnected cavities in all directions and makes the surface area of zeolite very large, so it is very well used as an adsorbent.
“Although synthetic zeolite has been widely produced, natural zeolite has an important role because of its abundant availability in nature, especially in Indonesia,” he stated.
One area that has abundant natural zeolite reserves is in Nagapenda Sub-district, Ende Flores Regency, NTT. According to Final Report of macro Mapping for type C Mining Material (NTT Mining and Energy Agency, 1992-1993), there was about 7.150.000 m3 zeolite reserve in the village of Ondorea, Nagapenda Sub-district, Ende Flores Regency, NTT, especially the mordenite type zeolite.
“But like with other conventional adsorbents, the use of natural zeolite as an adsorbent is not much in demand because it only targets metal selectively and the preparation for needed quantification is difficult,” he said.
To increase the selectivity and sensitivity of natural zeolite so that it can be used as an adsorbent, natural zeolites need to be activated and modified with other materials. One of the materials that can be used to improve the adsorption capacity of Cr (VI) is a material made of polymer material known as ionic imprinted polymer (IIP) material.
“Modification of natural zeolite with IIP is expected to increase the adsorption ability specifically for Cr (VI) with selectivity and sensitivity from various sample matrices. IIP material was chosen to be used in the modification of natural zeolite to function as an adsorbent because IIP has been known as a new adsorbent material with high selectivity,” he concluded.
Author: Fariz Ilham Rosyidi
Editor : Nuri Hermawan
Yantus A.B Neolaka, Ganden Supriyanto, Heri Septya Kusuma, Synthesis and Chracterization of Natural Zeolite with Ordered Ion Imprinted Polymer Structures (IIP@AFINZ) for Selective Cr(VI) Adsorption from Aqueous Solution, Moroccan Journal of Chemistry, volume 7, nomor 1(2019)194-210.
