Aaron R. Hutchison

Mercury Pollution and Remediation: The Chemist's Response to a Global Crisis

Environmental mercury pollution is a growing global problem. Due to its unique properties, mercury has in the past been widely used by a variety of industries. This has led to the deposition of large amounts of mercury into the environment, where it is naturally redistributed but not naturally removed. In its methylated form, this mercury tends to accumulate in marine life, eventually reaching levels that can be toxic to humans. Fortunately a variety of remediation methods, including phytoremediation, filtration, and chemical precipitation, are currently in development. One precipitation leagent called MetX appears extremely promising. It binds mercury and other soft heavy metals irreversibly and produces precipitates that do not leach. This technology and many others holds the promise of a future victory over mercury pollution.

The removal of mercury from water by open chain ligands containing multiple sulfurs

Mercury pollution is a serious challenge faced by environmental chemists over the world. For several years now, our group has been developing new compounds to precipitate and thereby remove mercury from water. In this paper, we present a new family of alkyl thiol mercury chelates to add to the aromatic ligands we have previously reported. These new compounds are effective at precipitating mercury from water and with an excess of the best compound, removal is quantitative. Furthermore, the precipitates are stable and released little to no mercury back into solution during leaching studies.

Monomeric Group 13 compounds with bidentate (N,O) ligands

Abstract The bidentate ligand, Sal(tBu)H, is prepared by the condensation of one equivalent of a bulky amine with 3,-5-di-tert-butylsalicylaldehyde. When one equivalent of Sal(tBu)H is added to MR3 or AlMe2Cl, compounds are btained which have the general form: [Sal(tBu)MR2] (with M/R combinations, Al/Me (1), Al/Et (3), Ga/Et (4) and In/Et (5)) and Sal(tBu)AlMeCl (2). The compounds are characterized by melting point, elemental analyses, IR, 1H-NMR, and in the case of 2 and 3 by single-crystal X-ray analysis.

The four coordinate geometric parameter: A new quantification of geometry for four coordinate aluminum and gallium

The chemistry of aluminum and gallium compounds has long been a major area of research. Much of this interest stems from the compounds use as Lewis acid catalysts. Efforts to create better aluminum and gallium catalysts have often focused on the addition of new ligands to increase the Lewis acidity of the metals. However, a four coordinate Lewis acid catalyst generally must add a fifth substituent during its catalytic cycle, so the degree to which its geometry encourages this addition will also affect its activity. To help determine the degree to which a four coordinate compound is geometrically optimized to take on a fifth substituent, we have created the four coordinate geometric parameter (FGCP). The FGCP of a compound can be calculated by a simple formula utilizing the ligand-metal-ligand angles of the structure. A high FGCP value indicates a compound with an open space for a fifth substituent, while a lower FGCP value indicates a compound with a more tetrahedral geometry. A negative FGCP suggests a ...

Compounds Containing Five-Coordinate Group 13 Elements

The synthesis, characterization, and applications of five-coordinate group 13 compounds are examined and surveyed. The range of compounds covered in this study includes those with five separate ligands (called “Class A”), a single bidentate ligand (Class B), two bidentate ligands (Class C), tridentate ligand coordination (Class D), and tetradentate ligand coordination (Class E). Each class of five-coordinate compounds is further sub- divided into the possible “Types” of structures that may be envisioned to occur. Following an extensive (although not exhaustive) search of the literature it was found that the majority of the compounds fell into a very few Types in each Class. Thus, future reviews may focus more specifically on the details within these well-populated Types. Many of the possible Types of compounds had no members whatsoever, and thus provide clear targets for future research endeavors. As a striking example, no compound involving a single five-coordinate ligand (Class F) was found.