IT'S ELEMENTAL!
board" of modules encompassing fewer stages, inherently clean and direct routes, rapid reaction kinetics, high throughputs, high overall yield, lower waste, and substantially improved productivity IAN SHOTT, IAN SHOTT ASSOCIATES LTD. In today's world of process intensificaintermediate, and they successfully pro- tion, supercriticalfluidtechnology nanoSMIUM, USED PRIMARILY I N pen nibs and armor-piercing duce a sample that is purified and analyzed. technology, and "multidisciplinarianism," weapon shells, is the densest This is well received by the customer, who there is considerable scope for innovation. Coming back to osmium, it could conmetal in the periodic table. It then wants larger quantities and detailed can, however, typify an often large-scale pricing. It proves impossible to ceivably be embedded in a microreactor encountered chemical conundrum. On the fit it into existing equipment, and a sub- module where the oxide is retained and recycled while the reactants and one hand, it is very useful as the metal in a stantial investment is required products have low residence highly stereospecific catalyst, which is both for a dedicated, segregated, hightime, with the product "escapnonvolatile and nontoxic. In the develop- ly specified plant. The market is not yet established, cost is an ising" largely contaminant-free to ment world, it has enjoyed widespread use the next isolation and purificain directly synthesizing a range ofvaluable sue, and price sensitivity is crittion modules. In this world, all pharmaceutical intermediates. On the oth- ical. High capital expenditure multipurpose synthesis lines are er hand, its oxide is both highly toxic and and low occupacity mean proa "circuit board" of cheap-tovery volatile, with high physical penetra- duction costs are prohibitive, construct, high-throughput THIS ELEMENT tion of a variety of otherwise inert mate- and the opportunity is consemicroreactor and separator BROUGHT rials. Commercially, the oxide is used as a quently lost. The activation energy to convert an intellectual modules that are rapidly interTavmi BY. stain in microscopy , -RHODIA. curiosity into a commercial rechanged and recycled for prodThus, scale-up in conventional multiuct changeover. purpose plants poses three significant is- ality has not been overcome. This will be possible only if organic and sues: waste containment and treatment; The specialty chemical company Rhophysical chemists, material scientists, enproduct purification, as evenparts-per-bil- dia does have access to intellectual propgineers, and mathematicians interact at a lion concentrations cannot be tolerated; erty in this area and has undertaken some and decontamination of the plant and semitechnical trials and scale-up pilot-plant preindustrial conceptual level to rewrite equipment where the oxide will have pen- activity To my knowledge, only two or the chemistry books and make a breaketrated surfaces, particularly PTFE (poly- three other companies also have limited through in multipurpose plant thinking. operational experience but no fully comOver the past three decades, the electetrafluoroethylene) linings and joints. tronics industry has confronted this chalThis combination can result in the ne- mercial activity The cycle can be broken only if one sincessity to make an otherwise multipurpose plant dedicated, with the consequential gle opportunity is so certain, so large, so negative impact on capacity utilization and cost insensitive it can support the investoverall production economics. A frustrat- ment. Today, this type of opportunity is a ing cycle then occurs, whereby industrious rare animal and more probably in danger process researchersfindan elegant solution of extinction. to synthesize an otherwise difficult-to-make Standing back from this issue, we could be facing a huge generic problem with the combination of today's increasingly comOSMIUM AT A GLANCE plex chemistry and existing state-of-the-art Name: From the Greek osme, smell. multipurpose technology The latter is, in Atomic mass: 190.23. general, based on a simplifiedflowsheet of History: Discovered in 1803 by the Enlarge stirred-tank reactors that has essen- P O I N T E D One of osmium's major glish chemist Smithson Tennant in the tially existed for the past five centuries! uses is in fountain pen tips. residue left when crude platinum is Modernization has brought a plethora of new materials and instrumentation that lenge and made huge advances in moving dissolved by aqua regia. have increased the cost of fundamentally from valve technology to microchips. The Occurrence: Occurs in iridosule and in lowproductivity equipment trains.Thus, no enormous benefits in functionality and platinum-bearing river sands. discernable benefit in terms ofunit cost re- cost have been passed on to the public at Appearance: Lustrous, hard, silvery duction has resulted. large. The chemical enterprise now needs metal with a bluish tinge. Behavior: The pure metal is not toxic, Most organic synthesis routes to com- to seize its challenge and unlock the full but its volatile oxide is. Powdered osplex pharmaceuticals have numerous stages power of the periodic table for the benemium slowly gives off osmium tetroxwith high dilution and slow kinetics offer- fit of humankind and the consumer. ide, which is highly toxic and has a ing miserable overall yields and appalling strong smell. productivity These routes under batch con- Ian Shott has held senior executive positions Uses: The metal is almost entirely ditions are very complex and involve in- in the international pharmaceutical andfine used to produce very hard alloys with herently dirty chemistry with numerous chemicals industryfor thepast 20 years. He has other metals of the platinum group. side reactions. Anew vision for tomorrow spent much time living and workingin the U.K., could involve a type of process "circuit France, Switzerland, and the U.S.
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