Patents

The invention relates to an optical sensor system for detection of sub ppm levels of HCl gas. The invention involves fourteen different free base porphyrin embedded on thin layer silica plate as sub-ppm level of HCl gas detection device through colorimetric analysis. One of the porphyrine meso-5,10,15,20-tetrakis (3,4-dihydroxy phenyl) porphyrin freebase can deduct a flow rate less than 0.01ppm of HCl gas in less than 30sec. Different free base porphyrins act as HCl sensor for different concentration levels. The invention is particularly useful in detecting sub-ppm level of HCl gas in a very short time. Further, an array of different porphyrins can be embedded to detect the level of HCl gas in a quantitative fashion.