Separation of toxic heavy metal ions from waste waters, adsorbs them onto porous concrete adsorbents produced by calcining under given conditions

摘要

The heavy metal ions are adsorbed onto porous concrete adsorbents made using a calcining process. The porous concrete materials are untreated, or are alternatively manufactured by calcining. They are activated by calcining, to make the adsorbents. The calcining temperature is 30-1200[deg]C, preferably 50-700[deg]C. Heating duration ranges from 10 minutes to 7 days, but is preferably 1-24 hours. The adsorbent contains mainly tobermorite, especially synthetic 1.13 nm-tobermorite, and quartz. Grain sizes are 1mu m -10 mm, and especially 45mu m - 800 mu m. An independent claim is included for the method of making the adsorbent.