Comparison of Nitrate Biosorption in the Aqueous Solutions by Three Algae Species (Hypnea charaoides Lamx, Cheatomorpha antennina Borgessen, and Champia Kotschyana Harvey) and Application of Selected Alga in a Channel

It is very important to identify a low-cost biological biosorbent for nitrate biosorption from reclaimed water. This article peruses removal of nitrate by Hypnea charaoides Lamx, Cheatomorpha antennina Borgessen, and Champia Kotschyana Harvey algae from aqueous solution (the synthetic solution was artificially prepared in the laboratory) under different electrical conductivities (EC) (6, 9, and 12 ds/m), time (15, 67.5, and 120 min), and nitrate concentrations (50, 175, and 300 mg/L). Based on the optimization, the nitrate removal rate by Hypnea c. Lamx alga reached 86.68%, which was higher than Champia Kotschyana Harvey and Cheatomorpha antennina Borgessen algae. The rate of nitrate removal under optimal conditions by Champia K. Harvey and Cheatomorpha a. Borgessen algae was 76.48% and 39.86%, respectively. Therefore, Hypnea c. Lamx alga was used as a filter in a laboratory channel. The number of filters and contact time in nitrate removal in the laboratory channel were investigated. The statistical analysis revealed that the removal of nitrate is straightly proportionate to the number of filters and the time. Removal efficiency with an increase in the number of filters (to three filters) and contact time (of 3 days) increases. Based on the number of filters, the removal efficiency of nitrate reached 85.19%, which was higher than systems consisting of two filters or one filter. A system consisting of three filters is 37.3.1% higher than a system consisting of one filter, effective in removal efficiency. The effect of Hypnea c. Lamx alga on reducing EC was also examined. The results showed that Hypnea c. Lamx alga was effective in decreasing 38.92% of EC. By increasing the number of filters and contact time, the EC removal increased.