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What kind of phosphate is present in fertilizers?, some say that the

  1. Aug 9, 2011 #1
    What kind of phosphate is present in fertilizers?, some say that the orthophosphate is the one mostly used in fertilizers however some state otherwise, hoping you guys have the answer :)
  2. jcsd
  3. Aug 12, 2011 #2


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    Re: fertilizers

    They used to put "superphosphate" in fertilizer, which is a mixture of gypsum and monocalcium phosphate but nowadays they just treat insoluble calcium phosphate (Ca3(PO4)2) with phosphoric acid instead of sulfuric acid and make something identical without the gypsum and call it "triple superphosphate". Both products are chemically Ca(H2PO4)2. I've seen ammonium phosphate used as well. There is no single type of phosphate used (ortho or poly) but most is ortho I believe.


    My buddy Malcolm Beck has been watching the phosphate market for some time and he noticed that when the industry switched over to triple superphosphate the lawn problems began in San Antonio. He attributes it to the type of phosphate used but I'm unconvinced. I guess you could just add gypsum to regular fertilizer and make your own "super".
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