THE UV/HYDROGEN PEROXIDE PROCESS

Introduction. The application of ultraviolet (UV) light in combination with (as a catalyst for oxidation by) hydrogen peroxide (H2O2) has been successful for the removal of fairly dilute organic solvents from groundwater and less successful for the removal of concentrated and possibly more variegated, complex wastes from the tomato-processing and distillery industries. The chemical reasons for the mixed results will be explored here, and the economic feasibility of the process will be reviewed.

The Process Train. FMC/Southland Environmental claims that FMC is the "largest producer of hydrogen peroxide in North America" (6:2). It makes its product available, in part, through a skid-mounted waste treatment unit that is self-contained and so ready to operate upon arrival that: "The last thing you need is to manage another time consuming construction or pilot project" (6:1). So, the process itself is not revealed.

The U. S. Navy evaluated the process for use against groundwater contamination by organics and was far more revealing about the (simple) process train (8:1). The treatment system can be in one or more "oxidation chambers;" each chamber will contain a single "high-intensity" UV lamp mounted in a quartz tube (8:1). The wastewater flows in the space between the outer chamber wall and the inner quartz tube holding the UV lamp (8:1).

FMC's version of a peroxide treatment system, which may or may not

. . .
le the findings of this study (2) are directly refuted [later herein] by those of Weir and Sundstrom (12), they are confirmed in large part by the most comprehensive mechanism studies by Stefan and Bolton (10), also described below. The mechanisms at issue are direct photolysis (degradation of organics by light) by the UV lamp, oxidation of the organics by H2O2 (alone), and oxidation of organics by highly reactive hydroxyl radicals (OH-, primarily), formed through UV-catalyzed disassociation of H2O2 into two OH- radicals. The investigators reviewed here are all over the lot on these matters, but Beltr?n, Gonz?lez, and Gonz?lez decided that, at least for tomato waste, there was some independent, direct photolysis (18%) (2:2407), which was enhanced--though not feasibly enough--by addition of H2O2 (2:2408). Their ultimate conclusion is that UV light is primarily a catalyst for the "breakdown" of H2O2 to produce hydroxyl radicals, and those radicals cause the brunt of the oxidation (2:1601). At the outset they had said that UV and H2O2 are "both oxidants" (2:1597). Benitez and co-workers decided, at the end of their work, two mechanisms ("contributions") are at work in the degradation of protocatechuic acid: direct "photooxidatio
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Some common words found in the essay are:
Weir Sundstrom, Stefan Bolton, Gonzlez Gonzlez, North America, Sandall Rinker, Stefan Bolton's, UV H2O2, Tuhkanen Beltrn, Command NFESC, BOD COD, uv light, hydrogen peroxide, stefan bolton, hydroxyl radicals, weir sundstrom, uv radiation, direct photolysis, beltrn gonzlez gonzlez, gonzlez gonzlez, tuhkanen beltrn, uv/h2o2 process, keller sandall rinker, wastewater advanced oxidation, industrial wastewater advanced, rate constant =,
Approximate Word count = 2718
Approximate Pages = 11 (250 words per page)