Project Name: Mercury Absorbing Papers
Theme : Industry
Idea behind why we selected this Project: We decided to do this project to find a way to prevent the release of mercury into the environment from CFLs, industries and other man-made sources of mercury.
The Problem we Face: The present world has become conscious of the impact we are having on the environment. We have stated using CFLs, and other instruments which are said to be more environmentally friendly than the old incandescent bulb. But the CFLs have mercury in them which makes them extremely hazardous to handle. The coal industry is the biggest producer of waste mercury, and with the increasing demand of electricity this problem will just keep worsening. To prevent the widespread damage caused by mercury on the environment we have prepared an innovative solution.
Aim: To safely absorb mercury from its various sources and complex to form Cu2HgI4 (Copper Tetraiodomercurate).
Chemicals Required:Copper sulphate, Potassium iodide Apparatus Required: Bunsen burner, Filter paper, Beaker, Glass rod, Air-tight reaction unit.
The principle related to this experiment is to prepare coordinate compounds. The mercury first reacts to form HgI2. Then it further reacts forming HgI42- ions. These ions react with the free Cu+ions in the solution to form Cu2HgI4.
Take 1:2 ratio of copper sulphate and potassium iodide respectively.
Put the copper sulphate in a beaker with water and heat it on a Bunsen burner till it boils.
Then add the potassium iodide to the boiling solution. Keep stirring till all the iodine vapours (violet gas) is completely removed.
Then filter the solution present in the beaker.
The filtrate obtained is copper iodide, and it is applied on any available paper. These papers are known as copper iodide papers.
Then react this copper iodide paper with mercury vapours.
We find that the copper iodide reacts to form brick red coordination complex compound called Copper Tetraiodomercurat(Cu2HgI4)
We must wear gloves, face-shields, respirator cartridge.
Utility of the Project:
Copper iodide paper can be used in factories for effective treatment and disposal of cfc bulbs.
We can paste the copper iodide paper inside a heavy bottomed vessel which is air tight and when we keep a fused cfc bulb in it and it is crushed with the help of a crusher and heated, we find that mercury starts leaking and it is absorbed by the paper. Compared to the usual absorption with sulphur, this method is much faster.
Name of the School: Chinmaya Vidyalaya, Chennai.