CAMBRIDGE, Mass. - Phosphorus, a mineral element found in rocks and bone, is a critical ingredient in fertilizers, pesticides, detergents and other industrial and household chemicals. Once phosphorus is mined from rocks, getting it into these products is hazardous and expensive, and chemists have been trying to streamline the process for decades.
MIT chemistry professor Christopher Cummins and one of his graduate students, Daniel Tofan, have developed a new way to attach phosphorus to organic compounds by first splitting the phosphorus with ultraviolet light. Their method, described in the Aug. 26 online edition of Angewandte Chemie, eliminates the need for chlorine, which is usually required for such reactions and poses health risks to workers handling the chemicals.
While the new reaction cannot produce the quantities needed for large-scale production of phosphorus compounds, it opens the door to a new field of research that could lead to such industrial applications, says Bertrand, who was not involved in the research.
Most natural phosphorus deposits come from fossilized animal skeletons, which are especially abundant in dried-up seabeds. Those phosphorus deposits exist as phosphate rock, which usually includes impurities such as calcium and other metals that must be removed.
Purifying the rock produces white phosphorus, a molecule containing four phosphorus atoms. White phosphorous is tetrahedral, meaning it resembles a four-cornered pyramid in which each corner atom is bound to the other three. Known as P4, white phosphorus is the most stable form of molecular phosphorus. (There are also several polymeric forms, the most common of which are black and red phosphorus, which consist of long chains of broken phosphorus tetrahedrons.)
For most industrial uses, phosphorus has to be attached one atom at a time, so single atoms must be detached from the P4 molecule. This is usual
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Massachusetts Institute of Technology