Microalgae-derived nanoporous biochar for ammonia removal in sustainable wastewater treatment

Ammonia is a critical pollutant in biological wastewater and not easily separated mechanically due to similar physical properties (e.g., molecular weight, polarity, etc.) water. Currently, an agent for ammonia removal from using zeolites must be mined, which environmental-friendly. The development of sustainable absorbent ammonia-containing therefore desirable. Since microalgae can grow rapidly by feeding on waste nutrients up-taking carbon dioxide flue gas, it high interest used as bio-absorbent secondary treatment. problem statement this work explore understand the use source effective absorbent. In work, nanoporous biochar (NP-MBC) proposed synthesized formaldehyde-stabilized hydrothermal KOH-activated high-temperature pyrolysis. novelty that mechanism NP-MBC being uncovered via spectroscopic sorption analysis. Formaldehyde-stabilization maintains morphology particles higher quality pore formation during Pyrolysis temperatures up 700 °C improve structure surface chemistry NP-MBC, leading specific area 1137 m2·g−1 increased activation COO- groups adsorption. Further pyrolysis at 800 damages textual characteristics causing pores agglomeration lower best adsorption performance was obtained prepared with maximum 72 % (within 120 min) capacity over 69 mg·g−1. Nanoporous stabilized treatment are interesting paradigm convert particulate biomass feedstock functional material tunable properties.