removal of nitrate from aqueous solution using rice chaff

Background: nitrate is largely dissolved in the surface and ground water, due to its high solubility. continual uptake of nitrite through drinking water can lead to problems and diseases (such as blue baby) for humans, especially children.objectives: the aim of this study was to develop a new and inexpensive method for the removal of nitrate from water. in this regard, the possibility of using chaff for removal of nitrate from aqueous solutions was studied and the optimum operating conditions of nitrate removal was determined.materials and methods: this is a cross-sectional study conducted in laboratory scale. the uv spectrophotometer at a wavelength of maximum absorbance (220 nm) was used to determine the nitrate concentration. the effect of ph, amount of chaff, temperature, and contact time were investigated.results: the result of this study revealed that chaff as an absorbent could remove nitrate from solutions, and the efficiency of adsorption increased as contact time increased from 5 to 30 minutes, amount of chaff increased from 1 to 3 g, temperature increased in a range of 300 - 400°c and the amount of ph decreased from 10 to 3. the maximum adsorption rate was around ph 3 (53.14%).conclusions: it was shown that the removal efficiency of nitrate was directly proportional to the amount of chaff, temperature, and contact time but inversely to the ph. this study showed that nitrate removal by chaff is a promising technique.