OPTICAL SENSOR DEVELOPMENT FOR CR(VI) METAL ION DETERMINATION

• Main Author: Hapsari Soebiyanto, Lucky
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/34760
• Institution: Institut Teknologi Bandung

Heavy metals ions have long been known as one of common water pollutant components. The relatively low limit of human body’s tolerance makes heavy metals ions become a main parameter in determining the quality of water for everyday use. Therefore, various studies have been done to discover easy and inexpensive methods to examine the level of aforementioned ions compounds. Optical sensor is one of the most practical developing methods. In this study, an optical Cr(VI) sensing material has been prepared from Tetraethylorthosilicate (TEOS) compound by using sol-gel technique. 1,5 dyphenilcarbazide (1,5-DPC) was chosen as a ligand. A reaction in acidic condition results a change of colour of the sensor film into a typical violet with maximum absorbance 541 nm. The results show that the ligand could be successfully entrapped inside the sol-gel film and still maintain its reactivity as in solution. Application of the method in water sample analysis provides percent recovery of 98,077% with sensitivity of 0,065 ppm and 1,374 ppm Cr(VI) content. Reusability is found after Cr(VI) leaching process from the entrapped ligand with nitric acid solution.