Abstract:
This research studied the toxicity of smoke from joss paper burning to achieve guideline or methods for toxicity reduction. It was found that Kim-Chua which was widely used contained the highest amount of lead at 2.8 ppm. Sulfur which can turn into sulfur dioxide was also found in this type of paper. Lead and sulfur were also found in pulp which was used as a raw material, though at a smaller amount. It was possible that lead and sulfur accumulated in the white water circulation system. Therefore, waste water management is very important in making environmental-friendly joss paper. In this research, montmorillonite was used to remove lead and sulfur in whitewater as it is a good adsorbent for cation (Pb2+) and anion (S2-). In the solution contained 10 mg/l lead and 400 mg/l sulfur at 25ºC, pH 4.6, it was found that an increased amount of montmorillonite resulted in a decrease of adsorption capacity of lead and increased adsorption capacity of sulfur. From the thermodynamic studies, it was found that the adsorption process was endothermic and spontaneous. When the pulp contaminated with lead and sulfur was treated with montmorillonite and formed into paper, the amount of lead in the paper and its ash after burning was reduced.