Coffee ground biosorbent for nitrite and nitrate recovery and soil nutrient

Nitrate (NO3-) and nitrite (NO2-) are two forms of nitrogen that contribute to the occurrence of eutrophication if found in excess concentrations. Conversely, nitrogen is one of the major macronutrients required for healthy plant growth. The purpose of this work is to evaluate the recovery of NO3- and NO2- from aquaculture wastewater (AW) by adsorption using coffee grounds (CG) as a biosorbent. The influence of carbonization temperatures (200 – 700 °C) was studied. The result postulates that CG carbonized at 200 °C was the most effective in NO3- and NO2- recovery from AW, having more than 80 and 70 %, respectively. The potential of the spent CG for soil conditioning was also investigated by evaluating the germination index (GI). The findings showed that spent CG from AW resulted in high GI with 105.6 % after 72 h of incubation. CG biosorbent is a potential sorbent to recover nitrate and nitrite from wastewater. The spent or nitrate and nitrite recovered biosorbent can be reutilized as soil nutrient.