...read the wave

2006 Nano Biz...in depth... im detail


HENCI Technology Revolutionizes Ex-Situ Nanocatalysis

March 24, 2006 --- The New High Efficiency Nano-Catalyst Immobilization ( HENCI ) technology by Cross Technologies is unleashing, for the first time ever, the immense potential of nanocatalysis for large-scale Groundwater Remediation (GWR): to treat recalcitrant carcinogen-contaminated groundwater (often to potable quality) on-demand, at any throughput, in a small, inexpensive, well-head / point-of-distribution / mobile unit, by eliminating carcinogenics altogether (chemically breaking them down into benign species, not simply trapping them in a medium, concentrating them in an effluent or evaporating them to our air). With process-cost efficiencies literally orders of magnitude greater than conventionally available technologies, HENCI facilitates the use of nano-catalysts (NCs) in a completely new way, opening the flood-gates for the application of nanotechnology to environmental and industrial nano-catalytic and -sorbtive processes.

The new genres of nano-sized catalysts are very exciting. When polluted water is exposed to them, rapid and complete catalytic destruction, i.e. chemical breakdown to benign species, of at least 40 recalcitrant carcinogenic groundwater pollutants has been shown to take place. Pollutants include chlorinated alkanes, alkenes and aromatics, THMs, DDT, Lidane, PCBs, Dioxins, TNT, NDMA, Organic Dyes, dichromates, perchlorate, pharmaceutical residuals, and others of immediate concern, many on the EPA-'Hotlist' (section 307, CWA). Hence, the desire to use highly effective NCs for various large-scale ground water remediation (GWR) applications is well established. However, the attribute most important to their high-efficacy - their nano-scale size - is also their Achilles' heel, and has greatly inhibited their commercialization via both in-situ and ex-situ operation. Why? Firstly, no method for in-situ use of NCs has proven truly viable, including sub-surface injection, reactive barriers, or in-situ surface treatment (NCs added to surface-storage tanks to break down pollutants before water is used). This is because most NCs are themselves toxic, so any in-situ use necessitates that, after exposure, all the NCs, in turn, be completely removed from the treated water prior to use . Because these particles are so small (and numerous), high-performance R.O./Nano-filtration is usually required to accomplish such removal, rendering the overall operation much too expensive.

Thus, on-demand ex-situ use of NCs has been proposed as a superior alternative because it eliminates the need for post-reaction removal of the NCs by 'immobilizing' them (usually on or within a support media) - preventing them from entering into solution in the treated water in the first place. As such, ex-situ operation is theoretically conducive to more-efficient 'continuous' processing, e.g. in a flow-through reactor. Until HENCI, however, no immobilization technology was even close to being viable for field application, as all fell short of meeting the seven formidable engineering challenges / criteria necessary for cost-effective immobilization NCs for any practical applications :

  1. Complete Immobilization - no undesired release of nano-particles.
  2. Ultra-high Particle Loading Densities within the reactor to fully exploit their high SA/mass ratios, or over about 25x10 15 particles per cubic inch of reactor volume.
  3. High Mass-transport Efficiency
    1. Micro-homogeneity - particles are immobilized in an evenly spaced, three-dimensional mono-dispersion through which the untreated water flows, exploiting NC's extremely high reactive surface area.
    2. No Particle Surface Coverage -100% of each catalyst particles' surface area is directly exposed to reactant
  4. High Momentum-transport Efficiency - high linear velocities with ultra-small pressure drops.
  5. Complete Scalability to commercial-volume treatment w/ >99.999% conversion efficiency of even ppb-level pollutants.
  6. Low Cap. & Op. costs : no expensive media or polluted effluent disposal issues; ambient operation, no moving parts
  7. Potential for quick regulatory-agency acceptance - safe, easily-controlled operation, no add'l contact materials

HENCI-facilitated nanocatalysis meets all these criteria, and is thus uniquely poised to usher in a new era in GWR marked by our ability to easily process polluted groundwaters to potable quality with a true leap in environmental benevolence, let alone the benefits to be reaped in commercial applications.

Ken Cross


This story has been adapted from a news release -
Diese Meldung basiert auf einer Pressemitteilung -
Deze tekst is gebaseerd op een nieuwsbericht -


who is reading
the wave ?

missed some news ?
click on archive photo


or how about joining us


or contacting us ?


about us


our mission