STUDY OF ASENIC REMOVAL IN GROUNDWATER BY USING ACTIVATED COCONUT FIBER

Abstract

Coconut husk has been discharged a great amount from coconut wholesales and retailers in Vietnam. This
biomaterial is environmental friendly, available and recylable which are consisted of a multicellular fiber structure
with a large surface area with many pores. Therefore, coconut fiber has high ability to absorb pollutants especially
toxic heavy metals in water. In this study, the biosoption of modified coconut fiber was investigated for arsenic
removal in underground water. The affecting factors on arsenic treatment efficiency including mass of NaOH-
activated coconut fibers (NaACC), inlet arsenic concentration in groundwater, treatment time and pH of the
solution media were evaluated. The results showed that the adsorption capacity of arsenic in groundwater was
highest in the following conditions: 40g/l modified coconut fibers, initial arsenic concentration of 500 ppb, time at
72 hours reaching the maximum arsenic treatment efficiency about 15.5% at 72 hours treatment. In addition, pH
adjusted to 12, it was obtanied 78% arsenic depletion. This result revealed that coconut fiber has the ability of
arsenic adsorption, however, in order to improve the efficiency of arsenic treatment towards meeting national
standards for domestic water supply, it is necessary to continue to expand research that can use this material
combined with other materials to meet thê national current standard.