The optimization of Arsenic (As) phytoremediation by L. octovalvis was conducted in reed bed system. Factors for optimization were As loading (5, 22 and 39 mg/kg), retention time (14, 28 and 42 day) and flow of aeration (0, 1 and 2 L/min). Performance evaluation was based upon six observations; As in L. octovalvis, TF, percentages of translocation, As uptake effectiveness by L. octovalvis, bioavailable As and total extractable As removal in As-spiked sand. Based on the response surface methodology using Box-Behnken design, the optimization condition for As phytoremediation occurred at As concentration of 39 mg/kg on Day 42 with 0.22 L/min flow of aeration. The optimum condition model gives the removal of bioavailable and total extractable As at 94.8 and 72.6 % respectively. The other responses were As in L. octovalvis (1157.87 mg/kg), TF (1.62), percentages of translocation (46 %) and effectiveness of uptake As by L. octovalvis (17.1 %). By comparing the model with a validation run, the optimization condition error for all responses was below 10 %. Factor such as As loading, retention time and flow of aeration could affect the performance of As phytoremediation by L. octovalvis.
Keywords
- Arsenic
- Phytoremediation
- Optimization
- RSM
- Box-behnken