CA1120425A - Dehalogenation of halogenated compounds - Google Patents

Abstract

ABSTRACT

Process for degrading halogenated organic compound having C-halogen groups to remove halogen atoms from said compound by treating it with ultra-violet (UV) radiation and hydrogen. Process for degrading such compound by treating it in aqueous alkaline solution with UV radiation.

Description

BACYGROUND

Many halogenate(l coml)ounds are employed for a varie-ty of practical uses, e.~., as pesticides, soil fumigants, solvents, etc.. Many escape into the environlnent, as -For examl)le in manufacturing or application wastes and spills.
Some, such dS pes-ticides, are applied in such a manner as to becorne part of the enviromllerlt. It has been found tha-t a number of such compounds9 particularly though not necessarily polyha'logenated compoun(ls, are toxic to plant and animal iife. Although some o~ the compounds are bio~ and/or photo-degradable so that they soon disappear from the environment9 a subs~ankial number are resis~an~ to environmental degra~ation and re~ain in poisonous Form for periods as long as many months or years. As a result, a good deal of research has been done to find reliable and economiGal treatment methods to degrade such compounds into environmental'ly safe products.
Some ~ork has b'een done wi~h treatment of certain halogenated"compounds variously with UV radiation or with UV'radiation and oxygen~ air or ozone? To , inventor's knowledge, there'have been no prior teachings of the use of a chemical reduction treatmen~ employing UV and hydrogen free From any addecl oxidizer9 '' ' such as air or oxygPn per se, or the use of UV alone in which the compound is in aqueous alkaline solutions. ~.S. patent'399779952 teaches the required use of oxygen (or air) plus UV, preferably in'the presence of HCl catalyst. In column 1, -the patent mentions the use of carbon dioxide, water vapor9 air or .
hydrogen as carrier gases for gas phase reactionO The reference to hydrogen appears to be inadvertent since no one skilled in the art would use hydrogen within the context of an oxygen oxidation process. The hydrogen ~tould oxidize to ~tater and present a serious hazard of explosion.

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DRAI~II NGS

Figure l is a schematic drawing Qf apparatus used in the process.
Figure 2 shows comparative percent d'egradation of kepone in methanol solution'with $rea~ment by UV plus H~ and in alkaline methanol solution with ~.

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trea .,ent by U~/ alone~ UV i~lus 03 an(l UV plus H~. .
Figllre 3 sho~Js the comparative percent (legraclation of kepone in aqueous alkalirle so'lution by UV alone, UV plus 03 and UV plus t~2 Fi~ure 4 shows the compara~ive percen~ o~ max;mum chloride ions released froln kepone in aqueous alkaline solution by treatment with the three methods.
Figure 5 shows the comparative total percent degradation of Aroclor 125 in basic methanol by UV alone, UV plus 03, and UV plus H2.
Figures 6, 7 and 8 show the percent ~legradation of tlle individual com--ponents of Aroclor 1254 by treatment wi~h UV alone9 UV plus 03 and UV plus H2 respectively..
Figure 9 shows the-percent degradation of TBPA in basic me~hano'l by treatmen-t with UV alone~ UV plus 03', and UV plus H2.
Figure 10 shows the percent of maximum bromide ions relea.sed from TBPA
: using the three trea~ment`methodologies.

.' SUMMARY
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The treatment of a halogenated organic compound having at least one C~halogen group wi-th UV radiation and hydrogen in the absence of any substantial amount of oxidizing agent reduces the compound by breaking the carbon~halogen linkage and p~oducing halogen ions', thereby at.least partially dehalogenating the compound ~in the cas.e of a polyhalogenated compound). The treatment may also result in further.degradation of the at least partially dehalogenated compound. The process may be employed with monohalogenated comp.ounds~ ~u-t will more generally be used .~o treat'polyhalogenated compounds because of their yenerally'greater toxicity and resistance to environmental degradation.
. The process can be used general.ly as a means for dehalogenation and is .particularly.useful ih the treatment of contaminated efflllent wastes from manu' facturing processes or from contaminated water, soil9 sludges or other wastes already present in the environment.

; -3 2 V ~ 5 ,' T~le dehalogenatloll m2chanisms ~hich occur in the process are generic ~ nature. -rhey at-e operatîYe regardless of ~he structure of the compound or '' the preserlce of other substituents or molecu'lar conlponents7 such as oxygen, sul-Fur, -nitrogen, metals or the like. The effect of these variable manifesta-tions is primarily in the enercgy of the C-halocJen bond and can be compensated for by employing higher or lower energy UV radiation wlthin the stated range.
The halogen substi-tuents can include chlorine, bromine9 fluorine, and iodine.
The different C-halogen groups generally differ in bond energy. C-F ~roups, for example, generally have particularly high bond energies as compared with the other ~-halogen grouljs ànd require more energetic UV wavelengths in the dehalogenation process.
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Examples of compounds which are particularly suitable for treatment by the'UV plu's H2 process of the inven~ion because of their demonstrated or poten tial toxicity include but are no~ limited ~o kepone (and its gemdiol) decach'loropentacyclo(5.3 0 02'6 o3~9 o4,8 )decan-5-onei halogenated biphenyls;
halo~enated cyclodienes, such as aldrin, dieldrin, ancl hexach'lorocyclopenta-'dienes; dibromochloropropane; halogenated phthatlic anhydridesg such as poly~
bromophthalic anhydride; tetrachloroethyleneg polychlorodioxins such as tetra- -chlorodlben~odioxin; halogenated organic phosphatesg such as 2,2-dichlorovinyl~
~0 dimethyl phosphate (Dichlorvos).
The process can be employed in gaseous phase where the halogenated organic compound is gaseous or in the form of a finely divided liquid or solidt ' In such case, the hydrogen acts as diluent9 carrier, and reactant. ~Ihere the compound is in liquid or solid formg it is generally deslrable to dissolve it in a suitable solvent which preferably is substan~ially transparent -to the particular UV wavelengths. Use of a solvent is particularly advantageous where the compound is d contaminant which must be separated from other materials, such as sludye or mud.
The particular solvent used is determined by the solubility character-3D istics of the particular-h~logenated ompound. It can be, for exanple, water, .

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met lol, cthanol, 1- and 2-propanol, hexane, cyclohex2ne, acetonitrile, and preferably their alkaline solutions.
An a~,ueous alkaline solu~ion, where alkalinity is preferably produced by the presellce o-f alkali metal ions and preferably by means of an alkali metal oxide or llydroxide ~to minilnize potentially obstruc-tive anions), such as sodium or potassium oxides and hydroxides, is particu~arly useful in the case of ilalogenatetl organic compounds which have substituents'that react to produce soluble- alkali metal salts. Examples include but are not limited to kepone (which normally hydrolyzes to the gem-diol in the presence oF ~ater or atmos-pheric moisture); ary', compounds having aryl-0~ substituents~ e.g.? phénol-typecompollnds; diol-type compounds; carboxy'lic acids; anhydrides~ such as phthalicanhydride-type compounds, sulfonic ac'ids; anc', the like.
' Compounds ~Ihich are not soluble in aqueous alkaline solutlons can generally be adequately solubilized by means of a sui~able organic solvent.
Preferably, thoùgh not essentially, the organic so'lvent is renc,ered alkaline, e.~g.~ by add;tion of an alkali metal oxide or hydroxide~ ~ince it has been found tha~ an alkaline pH can result in more rapid and greater degradation. --Methanol is a preferrec, solvent because of its good solubilizing capability9 its good UV transmlssion properties, and its rela-tively low cost which is oF
particlllar importance in the case of large scale application.
The UV radiation~ as aforementioned 9 should be in the range of about - 1800 to 4000 A. Pre-ferably, it is'in the shorter wavelength portion of this O O O
range, ramely up to about 2537 A. ~lavelengths of about 2537A and 1850A are particular'ly prtferred because of the generally high absorptivity of halogen-ated organic compounds at these wavelengths. ' The hydrogen input., quantitatively, should be sufficient~ during thetime of the treating procedure, to be in stoichiometric equivalency to the number of halogen atoms to be removed, or in excess theretoO In the case of llquid phase solvent treatment~ the effective limiting value is the saturation concentration of the hydrogen in solution. Continued input of hydrogen to 'maintain saturation provides the optimum amount.

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~ ~ 2~2~i The process can be carried out at ambient temperature in relatively simple apparatus. T~e halogenated organic compound should receive maximum exposure to the UV radiation. This can be accolnl)lished by such state-of-the-art expedients as minimiziny the distance that the radiation needs to travel to or through the ~reatment volume; recirculation of the treatment mediumi turbulence-creating means such as baffles or ro~ors and the like. The process can be designed for batch or continuous treatment.
ft has also been found that substantial de~radation can be obtained by treatn!ent of the halogenated compound in a~ueous alkaline solution by treat-ment with UV radia~ion within ~lie stated broad and preferred ranges of wave-length. Such treatment is limited to compounds~ as aforedescribedg which are soluble in aqueous alkallne solution without requiring additional use of an organic solvent. In all other respec~s the aforediscussion of various aspects oF the process ancl generio applica~ion regardless of compoLInd structure and substituents are appl1cable to such process using UV radiation alone.

. DETAILED DESCRIPTION . - -Figure 1 shows a schematic drawing of a reactor as employed ln experi mental evaluation. U shaped UV ~ube 2 is positioned longitudinally in reactor chamber 3~ and is held in air-tight position by Teflo ~plug 49 and is connected-by wires 5 to a transFormer (not shown). Hydroyen gas is pumped in via inlet tube 6. Reac~ion solu~ion is pulnped in via inlet tube 7 and is continuously recirculated by a pump (not shown) via outlet ~ube 8. Vent 9 provides for the exit of volatiles.
As used in the experiments below the reactor diameter ~as 4 inches.
Capacity was 1.5 1. The lamp size was 15-1/4 tnches in overall length with an arc length of 24-1/2 inches and tube diameter of 11/16 inch Lamp input was 30~l and output intensity was 10.4~l. UV wavelength was 2537A.

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, :' . - . , Exa~ )le 1 ,,``',`

~epone Treatnlent: . .
Kepone wllicll has been used as an insecticide has posec~ Formidable ':
problems because of i-ts great toxicity and resistance to bio- and photo~
de~radatiorl in the environl1lent. It is hiyhly toxic -to normal'ly^occurrin.g de~rading microorganisms. Alt~lougll it can undergo some photodeconlposition when . ' exposed to sunlight to the di~lydro compound ('leaving a compound having 8 Cl substituents) this degradation produc~. does not signiFicant'ly reduce toxicity.
Kepone was made up into ~hree dif~erent stock solutions:
a. 212ppm in methanol; solution pH6.
b. 237ppm in.methanol alkalized to pH10 with NaOH.
' c. 23Qppm in water containing 5~ NaOHO
1.5 1 quantities of the kepone stock solutions ~"ere variously treated ' in the apparatus aforedescribed (UV ~ = 2537A~ wi th UV alonea UV pius 03 at an ozone Flow rate o-f 0.~1- l/min. and UV plus Hz at a hydrogen flow rate of 0.75 l/min. '' ' Samples were prepared For quantitative gas chromatographic analysis in the following manner.
1. Measured volumes of the samples were neutralized with.ULTRE)~
20 (Cl-free~ ni tric acid9 if basic. ' -' 2. The samples were evaporated to dryness.

3. . The dried sample was diluted to 100 ml with 6~ nlethanol in benzene.
The resulting solutions ~"ere analyzed on a Hewlett-Packar~Z'5750 with electron capture detector. The Following conditions were used:
- injection port temperature - 3û0C .
- .'detector temperature 300C
- oYen temperature - 250C
- gas flow - 50 ml/min Ar/CH4 r(~
column - 10% [~C 200 on Chromoso HP 'IOO/200 The aqueous NaOII solutions wcre analyzcd on a llewlett-Pack~rd 3880 using the following oonditions:
- injection port temperature - 200C
- oven temperature - 180C
- gas flo~ - 45ml/min AE?/C~
- column -- 5~ OV-210 on 100/120 GC~
Chloride ion concentration was also determined on all of the samples. An Orion~solid state chloride ion electrode was u_ed for this purpose. Salllples in methanol were prepared by neutralizincf 5 ml of the sample with ULT~X nitric acid 10 Following evaporation to d~yness, the samples were dissolve~d in 8 ml of distilled water. In the case of the aqueous sodium hydroxide solutions, 10 Tnl samples were neutralized with ULTE~nitric acid before the analyses. Chloride ion concentrations were determined by ccmparison to standard curves generated frcm sodium chloride standards containing equal am.ounts of sodium nitra-te as the samples.
During the course of -the experimental runs, samples were taken at 15, 30, 60, 90 and 120 min. (+180 min for aqueous NaOH solution treated with W plus H2) to determine rate of degradation with -time.
Table 1 gives the results ob-tained in tenns of the remaining c~ncentration of kepone at the end of the indicated time period and the percent degradation.

Initial Sample Treatment ConditionsFinal % Degra-Conc. ppm Conditions Gas Time Conc. dation 212 Methanol 2537A120 min. 177 ppm 16.5P6 pl~l 5 Hydrogen 237 Methanol 2537A120 m~.155 ppm 34.69 pH 10 237 Methanol 2537A110 min. 190 ppm 19.8%
pH 10 OzonOe 237 Methanol Z537A120 min. 115 ppm 51.5~6 pH 10 Hydrogen 230 5~ Aq.NaOII Sol.2537A120 min. 140 ppm 39.1 pH ~ 14 230 5% Aq.NaOH Sol.2537A120 min. 181 ppm 21.3 pH > 14 Ozone 230 5% ~.NaOH Sol.2537A120 min37 ppm 83.9%
pH > 14 Hydrogen 230 5% ~q.NaOH Sol.2537A180 nun. 12 ppm 94.8 pH > 14 Hydrogen . ~

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~.` ' Table 1 and I;igure 2 shaw the substantially higher ~ de~Jradation at two hours by the basic n~thanol treabment with W plus ~12 as ccmpar.ecl with the othe~r treatn~nt methodologies. They also indicate that, althouqh the W
plus H2 treatment with non-alkalized methanol(pll 6) yives appreciable reduction, the alkaline m~tnanol gives very considerab.ly improved results.
Figure 2 also shows the considerably higher rate of reduction by the W
plus H2 treattnent.
Table 1 and Figure 3 shaw the very substantially higher rate and percent degradation produced by the W plus ~l2 treatment in ac~ueous NaOI-I
as canpared with the UV alone and W plus 03 treatments. At the end of 3 hours, the W p3us H2 treatment almost completely removes the kepone. These degradation results are substantially verified by Figure 4 which shcws the percent of free Cl ions released as a function of time for the W
alone, W plus 03, and UV plus ~l2 treatments. After 3 hours only about 26.5%
of the chlorine appears to rernain in C-Cl group ccmhination in chlorine-degraded products. At 120 minutes about 50.5% of the chlorine has been transformed into free ions by W plus H2, about 23% (less than one-half) by W, and only about 16.5% by W plus 03. These results indicate that as many as 6 to 8 chlorine atoms are removed frorn the kepone molecules by the W plus H2 treatment.
It should be noted that although the results obtained with W alone in aq~leous aLkaline solution are not as good as those produced by the W plus H2 treatment, substantial degradation is obtained, so that this treatrnent can be useful in the case of halogenated organic compounds which are subs-tantially soluble in aqueous alkaline solution as aforedescribed~
Exar~ple 2 Treatment of Polychlorinated biphenyl (PCB):
Aroclor 1254 is a mixture of the higher chlorinated biphenyls contain-ing 54% chlorine by weight (an average of 4.96 chlorine atcms per r~lecule).
A typical analysis of Aroclor 1254 is presented in Table II (Versar Inc., 1976).

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q`~BIE II

EmpiricalMolf~eular ~o. of Chlorine No. of FormulaWelghtper BiphenylWt ~ChlorineIs~merW~ht C12H10 154 0 0 1 <0.1 C121l9C1 188 1 18.6 3 <0.1 Cl2H8Cl2 222 2 31.5 12 <0.5 C12~17C13256 3 41.0 24 C12H6C14 290 I 48.3 42 21 C12H5C15 324 5 54.0 46 48 C12~l4C16358 6 58.7 42 23 C12H3C17 392 7 62.5 24 6 C12H2C18 426 8 65.7 12~:0.01 Aroclor 1254 is slightly soluble in water, having an overall solubility of 1.2X10 2mg/1. Solubility of the various components varies form U.0088 mg/l for the hexachlorobiphenyls to 5.9 mg/l for the monochlorobiphenyls. rhe vapor pressure for the 1254 mixture is 7.71X10 5mm Hg. q~heoretical half-life from a l-meter water oolumn has been calculated as 1.2 minutes. qhus ~roclor 1254, like many other slightly soluble chlorinated compounds, is readily vaporized frc~n the surface of water. Sueh vaporized c~ound could, therefore, escape degrad-ation treatment.
Aroclor 1254 was dissolved in methanol allcalized to pH 11 with NaOH to make a 10.92 ppm sto k solution. 1.5 1 portions of this stock solution were treated with W alone, W plus ozone at an ozone flcw rate of 0.41 l/mm., W plus hydrogen at a hydrogen flcw rate of 0.75 l/min. for 120 nunutes each in the reactor aforedeseribed. Samples of ~, 8 ml each were talcen every 15 minutes.
Analyses were perfonred on the 15-, 30-, 60-, 90-, and 120-minute samples.
Quantitative analyses for the PCBs were performed on a Hewle-tt-Packard 3880 gasehrcmotograph with an EC-Ni63 electron capture detector. G.C. conditions were asfollc~ws:
- injection port temperature - 200C
r 30 - detector temperature - 300C
- oven temperature - 220C
.. ~ ,~
- gas flcw - 50 ml/min Ar/CH4 wc/

- Column - 15% OV-17, 1.95~ QF-l on 100/120 GCQ
~he samples were prepared for analysis by neutraliæing a kncwn volume with UL5`REX nitric acid, follcwed by evaporation of the solutlon to dryness at roc~l temperature. trhe samples were brought up to 10 ml with pesticide grade he~ane.
- Stock solutions were treated in -the same manner to ensure that there was no loss frcm evaporation.
Areas under the individual peaks were measured with an electronic in-te-grator and ccmpared to standard curves to de-termine the concentration. Peaks 1-9 in the chromatogram were nonitored individually as well as the total area ; 10 under peaks 1-9. No attempt was made to identify the individual cc~ponents.
The results of the G.C. analysis of -the Aroclor 1254 degradation samples are presented in Figures 5-8. ~igure 5 shc~s the total concentration of chlor-inated biphenyls remaining as a Eunction of time for the -three treatment methodologies. As indicated in -this figure, the W plus H2 treat~ent is more effective than either W alone or W plus O . The initial rate for the W

plus H2 treatment is significantly faster than the other treatmen-t me-thodologies even though the final amount degraded for the W alone and the UV plus H2 af-ter 2 hours is apprcIximately -the same.
Figures 6-8 show the concentration of the individual chlorinated biphenyl cc~nponents as a f~mction of time for each treatment methodology.
Reten-tion time increases with the percentage of compound chlorine. Inspection of these figures shcws the rapid degradation of the high chlorinated biphenyls (peaks 5-9) with all treatment methodolcgies. m e lcwer chlorinated biphenyls disappear at a slower rate and even increase in concentration in the W alone and W plus O3 treatments. These curves are consistent with kncwn mechanisms for photodegradation of PCBs.

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Table III silows the total final concentrations of all of the PCB com-ponents and their total % dc~radation at the end of t~lo hours. ~:.

TABLE III
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ppm Final %
Treatment Concentration Degradation UV 0.93 ~1.5 UV-~H2 0.5 95 ~- UV-~03 3.49 68 , - ' ' ' ' ' Tests of the stock solution treated with hydrogen gas only, showed tha-t .
substantially none Or the PCB was los~ by vo1atilization. The degradation test results, in ~act, show an increase in the more volatile components (low chlor inated species) which is indicative of photochem;cal react;on.
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Example III
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' Treatment of tetrabromophthalic anhydride (TBP~):
TBPA ;s a high melting white crystalline material wh;ch is ;nsoluble ;n .
- water and sparingly soluhle in methanol. In basic methano1~ e.g., methanol rendered alkaline with NaOH, the anhydride functional group is reactive, form-ing the sodium salts and the methyl esters.
A weighed amount of TBPA WdS dissolved in methanol alkalized.to pHll to make a 100 ppm stock solution. 1;5 1 portions were treated with W alone, UV and o~one at an ozone flo~ rate of 0.41 l/min., and UV and hydrogen at a hydrogen flow rate o-F 0.75 l/min. in the reaotor aforedescribed. Sanlples of each treatrnent methodology were taken at 15, 30a 60, 90 and 120 ~inutes for analysis.
u~` The analyses were made using a ~ater ~high pressure liquid chromato-graph with-a 2537A detector. The carrier solvent was methanol and the flow - . .

~ 2 ~ ' rat as 1 m~ in. Salllples were inj~cle~l into the LC ~lithout any pretreatment.
The TBP~ concentration o~ the treated samples was obtained by co~parison to a stan~drd curve.
Brolllide ion concel7trations were measLIred with an Orior(~ romide elec-trode. Samp'les were prepared by neutralizing 5 ml o~ each solution with Ultrex `~
nitric aci~'. The resulting methanolic solution was evaporated to dryness and -then diluted to ~ ml wit~ clistilled water. Bromide ion concentrations were calculated by comparison'with a standard curve constructed from NaBr standarcls ' of known compositionO
'~ The results obtained from the l.C analysis o~ the.TBPA concentration of the samples are presented in Figure 9. The UV alone and UV plus 03 da~a appear to be very erra-t1c. This erratic appearance is due to ~he forma~ion of decom-position produc-t~ probably the tri- or di-brominated product which is not separated from the original TBPA peal~. Figure 10 shows tlle comparative forma tion af Br ion as a functioll of time for ~lle three methodoloyies and îs a moreaccurate indication of debromination than in Figure 9.
The brolnide analysis correlates well wi~h the LC analysis.of TBPA when ,; .
. treated wi~h UV p'lus H~. Upon treatment wit~l UV plus H2~ the TBPA is decomposed extremely rapidly during the first 15 minutesa after which T~PA degradation and ~0 bron~ide fornlation slo~ down. The lowest TBPA concentration (~ 16~ of the original) coupled ~ith the highest bromide concentration obtained (~ 50 ppm) in~icate that the molecules were completely debrominated. An equilibr'ium is then established between the TBPA and the resultant phthalic anhydride. 'To debrominate the remaining TBPA, this equilibrium mus~ be shifted.
Both the UU.alone and the UV plus 03 approach the three bromine removal level but a~ much slower rates. Wi~h these treatment methodologies~ several other compounds also appear in significant quantities on the LC chromatogramsO
These subs-tances did not appear in substantia'l quantities when the TBPA was treated with UV plus H2.

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2~
Thus, the UV plus li2 t1eatment in basic methanol not only results in significant'1y 1nore rapid degrddatio1) oF TBPA than UV alone or UV plus 03 but in different ~ecomposit;on pro~iucts.
It is clearly apparent from all of khe foregoin~ data that degradation of haloyena'ted organic compounds by treatment with UV plus i12~ preferably in alkaline solution, provides an effectiYe and economical means For removing such co!npol1nds' from mAnufacturi1lg effluent and/or the environ1llent~ It has'also been `shown that the treatmen~ of such compouncls with UV alone in aqueous alkaline solutions also providès significant degradation. By "UV alone"9 as used ;n ti!e speci.fica-tion ancl claims, is meant treatment with u'1traviolet radiation~ithou-t additional chemicai treatment other than the use o~ a solvent for the halogenated compound. The term "aqueous alkaline'solukion" means a solvent free from additional or.~anic solvent.
' Although t'his invention has beendescribed w;th reFerence to illustra-tive embod1ments thereo~, it will be apparent to those skilled in the ar.t that ' the princ;ples o~ ~h;s invention can be embodied in other forms but wlthin the scope o~ t'he claims.

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Claims (8)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Process for degrading a halogenated organic compound having at least one carbon-halogen group in such manner as to remove halogen from said compound, said compound being of the type which forms alkali metal salts when treated with an aqueous alkaline solution containing sodium or potassium ions, comprising, dissolving said compound in a solvent comprisiing an aqueous alkaline solution containing sodium and/or potassium ions, said solution being substantially free from organic solvent, with ultraviolent radiation in the range of about 1800 to 4000.ANG. substantially in the absence of any other compound treating agent.

2. Process of Claim 1 in which the compound has a plurality of carbon-halogen groups.

3. Process of Claim 1 in which the solvent is a solution of sodium and/or potassium oxide and/or hydroxide.

4. Process of Claim 1 in which the ultraviolet wavelength range is about 1800-2540.ANG..

5. Process of Claim 2 in which the ultraviolet wavelength range is about 1800-2540.ANG..

6. Process of Claim 3 in which the ultraviolet wavelength range is about 1800-2540.ANG..

7. Process of Claim 1, 2 or 3 in which the compound is kepone.

8. Process of Claim 4, 5 or 6 in which the compound is kepone.