Progress 10/01/04 to 09/30/09
Outputs
There has been no evidence of progress of this project from Dec 2006 to May 2007. Objectives continue to shift and final product has yet to be synthesized. Therefore goal cannot be met.
Impacts
Without synthesis of final product this project has not impact. Although project is feasible, the economics is still unknown.
Publications
- No publications reported this period
|
Progress 01/01/05 to 12/31/05
Outputs
Re-evaluated the water-soluble phosphine synthesis. Investigated the possibility of using air- and moisture-stable tetraethyl ethylene-diphosphonate and/or 1,2-bis(r)ethane as starting material, reducing it with lithium aluminumhydride, LiAlH4 to generate the highly toxic and pyrophorric phoshorus(III) hydride in-situ, followed by its formylation in a second reaction vessel to give the water-soluble 1,2-bis(bis(hydroxymethyl)phosphino)ethane. This reaction was designed based on syntheses reported in the literature. The product was a water-soluble pale yellow paste. The paste however contains side products resulting from the quenching of LiAlH4 with methanol. Extraction in ethanol and product isolation and characterization using 31P NMR points to the formation of the sought after water-soluble diphosphine. However, there was also some either starting material or oxidation product present. The reaction was repeated using 6M HCl to quench the excess LiAlH4. The final
product, from 31P NMR data contained several phosphorus-containing compounds. This, a result of several side reactions occurring, an observation that has been noted in the literature for some of this class of reactions. 1,2-bis(bis(hydroxymethyl)phosphino)ethane was synthesized. However the synthetic procedure requires improvement. The syntheses were repeated with air- and moisture-stable tetraethyl ethylene-diphosphonate and tetraethyl methylene-diphosphonate as starting materials, reducing them with increased amounts of lithium aluminumhydride, LiAlH4 to ensure all the starting material was reduced. The expected products were the water-soluble 1,2-bis(bis(hydroxymethyl)phosphino)ethane and 1,2-bis(bis(hydroxymethyl)phosphino)methane respectively. To my knowledge 1,2-bis(bis(hydroxymethyl)phosphino)methane has not been previously synthesized. In both syntheses performed, a white precipitate and a pale yellow to clear supernatent were separated. However characterization using 31P NMR
to determine the success or failure of the syntheses has not yet been carried out due to instrument break-down.
Impacts
The coal industry in West Virginia, one of the states largest industries, has supported numerous communities statewide for generations. The current methods of redressing the acid mine drainage problem using metal ion precipitation employing multiple ponds are unachievable for a multitude of smaller mining operations, threatening the continued business. Such mine closures would adversely affect the mining communities' economic well-being and burden the state - and ultimately the tax-payer - with the cost of treating the acid mine drainage from the resulting abandoned mines. Such cost estimated to perhaps run into the tens of millions of dollars per year. The envisioned success of this project is the development of the water-soluble P-, N-, O-donor ligands (attached to silica gels) to complex metal ions out of aqueous solution. These used in tandem with the traditional precipitation methods would negate the need to use multiple ponds to achieve mandated metal ion
concentration levels in the water discharged into the environment by coal mining operations. The result would be the continued survival of a multitude of mining operations, supporting their communities, and the staving off of the possibility of the state incurring costs running into the tens of millions of dollars per year to treat acid mine drainage of the otherwise abandoned or closed mines.
Publications
- No publications reported this period
|
|