Fluoride Action Network

Efficiency of Portland Pozzolana Cement as an adsorbent in removing excess fluoride from groundwater

Source: Groundwater for Sustainable Development - Volume 9 | August 3rd, 2019 | By DS Shyamal and PK Ghosh.
Location: India
Industry type: Water Treatment

Highlights

  • Drinking of fluoride contaminated groundwater causes dental and skeletal fluorosis.
  • High concentration of fluoride (>1.5 mg/L) has been reported by Central Groundwater Board of India in Mathura District of Uttar Pradesh.
  • Portland Pozzolana Cement used as an adsorbent, reduces fluoride up to 86% and 54.15% from synthetic water and groundwater respectively.
  • PPC as an adsorbent has been suggested to be used in combination with other defluoridation techniques.

Abstract

In this study, the efficiency of Portland Pozzolana Cement (PPC) as an adsorbent was investigated in removing fluoride from synthetic water by providing a layer of cement paste on the inner side of mud pots. After 27?h 86% reduction in the concentration of fluoride was observed from an initial concentration of 5?mg/L. The adsorption capacity of cement paste was found to be 0.25?mg/g. Adsorbent showed significant removal over a wide range of pH (2–12) and highest defluoridation was obtained at a pH of 2. The kinetic study revealed that adsorption of fluoride follows Pseudo-second order kinetics.

Further, the efficiency of PPC as an adsorbent was investigated in removing fluoride from groundwater. The ground water sample was collected from a village of Uttar Pradesh, India (Karahari, Mathura), having an initial fluoride concentration of 5.06 mg/L. In the case of ground water, the defluoridation efficiency of adsorbent was found to be 54.15%, which is lower than that observed in the case of synthetic fluoride solution prepared in the laboratory.

For a relative understanding of the efficacy of the adsorbent, the Nalgonda technique was also used on the same groundwater and results were compared.