3,202,478 3. A. 0.1% of sodium carbonate Na2CO3 in aqueous solution aqueous solution. Other compounds of ammonia, such (based on the total quantity of the solution of CuCl2 as (NH4)2CO3, CO(NH2)3. may be used in place of in the reactor 2) is added to the solution in the reactor, ammonium hydroxide NH4OH. The following reaction whereupon the following reaction commences, - will then take place when air is passed into the solution (4CuCl2)--12H2O--6O2--12Cu->4(CuCl2:3Cu(OH)2) as described, (micronised) (2) The air heater 7 is then turned on (if not already running The resulting insoluble tribasic copper chloride is "mi on heat) and delivery of pre-heated air under pressure Cronised' and, after decanting and washing, can be used to the reactor 2 is continued until test samples taken at to carry out the method of manufacture described here intervals of time from the solution within the reactor 10 in above. For all subsequent manufacture in the reactor, show, by comparison with each other, that the reaction no further ammonium hydroxide or other compound of according to Eq. 2 has practically ceased, or has reached ammonia is required. Between 0.05% and 0.1% of its economic limit. When this occurs, sodium carbonate sodium carbonate Na2COs is used instead in the manner in aqueous solution is added to the solution in the reactor already described hereinabove. The ammonium catalyst 2 in order to neutralize the small quantity of residual is employed once only (to start the plant working) and, copper now remaining in solution as CuCl2, since the since micronised tribasic copper chloride for all subse reaction indicated in Eq. 2 will not proceed entirely to quent manufacture is abundantly available, the am completion unless the running time is uneconomically monium catalyst is never used again. The reason for prolonged. The weight of sodium carbonate required this change of catalyst is that the micronised tribasic for this purpose will not usually exceed 5% of the total 20 copper chloride formed when sodium carbonate is used weight of the micronised tribasic copper chloride already as a catalyst possesses an even higher percentage than formed in the reactor 2 by the preceding chemical reac 66% of particles of a size less than three microns, tions. The liquor, containing the micronised tribasic thus giving the product even greater fungicidal activity copper chloride in suspension and approximately 6% than when an ammonium catalyst is used. of sodium chloride in solution, is now discharged from For electro-chemical reasons, the column of bars of the reactor through a delivery pipe 8 and run into suitable metallic copper inside the reactor 2 (all of which, filters for washing, drying and the like in known manner. since they rest upon each other, are in electrical con The air-heater 7 may be of conventional design, includ tact) must, in addition to being immersed in the solution ing an inlet 9 for admitting dust-free atmospheric air of CuCl2 in the reactor, also be exposed to the air above under pressure, a source of supply 10 of heat-energy 30 this solution, i.e., above the level 6, in order that the (e.g., steam, hot water, hot waste gases) and an outlet reaction may proceed efficiently. It has been found for waste 11. The heater 7 may of course be heated that for every 1'0' depth of bars of metallic copper im in any desired manner, such as electrically. mersed in the solution, 1'8' to 2'0' of the bars should The quantity of micronised tribasic copper chloride be exposed to the air inside the reactor above the solu manufactured by the novel method of the invention is tion. The ratio is of the height of the immersed bars approximately four times the quantity of micronised to the height of the exposed bars therefore, approximately tribasic copper chloride added to the reactor at the 1:1.8. New bars of metallic copper are added to the top commencement of operations. Clearly, if X units of of the column as the bars already in the reactor become micronised tribasic copper chloride are added to the 40 used up. - - reactor to commence operations, the yield of micronised - - - Example tribasic copper chloride at the conclusion will be 4X units. Since, however, from this 4X units, X units must 200 lb. of micronised tribasic copper chloride were put always be returned to the reactor in order to repeat the into the reactor. To this, 340 lb. of commercial hy process, the net yield, or quantity manufactured, is 3X drochloric acid containing 30% of HCl were added to units each time the reactor is discharged on completion 45 the reactor, water being added to bring the level of the of the process described above. This is clearly indicated solution up to 30', thus producing a strong aqueous in Eqs. 1 and 2 from which it will be seen that, theoreti solution of micronised CuCl2 in the -reactor. The pre cally, for each equimolar quantity of micronised tribasic heated air delivery to the reactor was started and, after copper chloride added to the reactor (see Eq. i., four one hour's running time and with the pre-heated air equimolar quantities are yielded (see Eq. 2). 50 still being delivered to the reactor, 1 lb. of sodium car In order to start the process in the first instance, and bonate in aqueous solution was added as a catalyst to the thereafter to repeat it, an initial quantity of micronised solution of micronised CuCl2 in the reactor, when the tribasic copper chloride must be made. This can be done reaction indicated in Eq. 2 commenced. The pre-heated by taking a given molar quantity of ordinary tribasic air delivery was continued for a further three hours (mak copper chloride (i.e., as manufactured by the known 55 ing a total of four hours running time) when test samples method of chemical precipitation) and adding thereto the taken from the solution in the reactor showed that the molar quantity of hydrochloric acid required to bring reaction had proceeded as far as was practicable. With the pre-heated air still being delivered to the reactor, 15 it into solution. lb. of sodium carbonate in aqueous solution were then CuCl3Cu(OH)--6HC1->4CuCl2-4-6H2O (3) 60 added to the (now very weak) aqueous solution of CuCl2 If one attempts to oxidise the resulting solution of CuCl2 in the reactor, when the following reactions took place, to tribasic copper chloride by passing therethrough either cold or heated atmospheric air under pressure and bubbling such air from the bottom upwards through the +4NaCl--CO, (5) solution in which are immersed bars of metallic copper, 65 2CuCl2-1-3 (Cu(OH)3. CuCOs)--3HO only an extremely slow reaction takes place and the ->2(CuCl2:3Cu(OH)2)--3CO (6) solution therefore changes only very slowly, while the thus precipitating a very small quantity (approximately product thus obtained is of a relatively coarse nature, 20 lb.) of ordinary (i.e., not micronised). tribasic copper since it is not micronised. If, however, a small quantity chloride. The reactor was then discharged, the mi of a suitable soluble catalyst is added to the Solution, 70 cronised tribasic copper chloride washed, dried and the reaction will take place to form micronised tribasic weighed, and found to be 710 lb. Therefore, the actual, copper chloride when air is passed into the solution in or net, yield was 710-200-510 lb. After drying, and the manner described. A suitable catalyst is ammonium . when analysed, the copper content of this batch of hydroxide NH4OH, containing approximately 0.1% by micronised tribasic copper chloride was found to be weight of NH3 based on the weight of CuCl2 in the 75 58.9% and the chlorine content was found to be 16.53%, 3,202,478 S 6 the hydrochloric acid and sodium carbonate consump It is much easier to prepare and apply than Bordeaux tion being respectively 0.68 lb. and 0.033 lb. per lb. of mixture, since it is a free flowing powder and it is ready micronised tribasic copper chloride manufactured. for immediate use by stirring into water and will not set It will be evident that to carry out this process, the acid tle out during spraying. It is also much less corrosive to proof reactor can be of any size provided the fundamental Spray nozzles, and will not cause blockage. conditions are fulfilled. The acid-proof reactor as de 5 The following are some of the crop diseases which can scribed hereinabove is 8’6” tali and 3’6” in diameter, with be controlled by Microcop. The concentrations of Micro an open top, can manufacture 2,040 lb. of micronised tri cop given, in Ibs. per 100 gals. water, are for use with basic copper chloride containing 58.9% of copper per day high voluime sprayers, at a rate of 100 gals. spray per acre, of twenty working hours (five hours per batch). (A total liness otherwise stated. If low volume equipment is em of one hour is required for charging and discharging the 0. ployed, the concentration should be adjusted to suit the reactor.) This reactor forms part of a small pilot plant sprayer by reducing the amount of water. from which the foregoing data has been obtained. It will also be evident that long acid-proof channels, filled with - Lbs. per Renarks bars of metallic copper and fitted for preheated air de Crop Disease 100 Gals. gals. per livery, and of any desired depth, width and length, can be water ?CT6 used to carry out this process, the strong solution of Bariana.------Leaf spot (Cercospora 3 150-200 micronised CuCl2 entering at one end of such channels, m/?8de). the micronised tribasic copper chloride thus manufactured Betelevine- -- Wilt disease (Phyto phthora sp.). in its passage through the channels leaving at the other end 20 Cutilin------Blight------of the channels, in suspension in the weak micronised Cotton------Angular leaf spot.------. Citrus------Black spot (Diplodia. CuCl2, for further treatment. 2tatensis). The volume of pre-heated air required to carry out this Brown rot (Botrytis |}|| ------process is many hundreds of times greater than-or in cierea). Melanose (Phomopsis ? ------excess of-the theoretical requirement of the oxygen con 25 citri). tent indicated in Eq. 2. Naildosporium head rust herbarum). (Gla- 2 ? ? ------Analysis of our technical grade of micronised tribasic Scab (Sporoirichun citri)-- 8------Coffee------Ileafrust or leaf disease 2% ?ö0—?00 copper chloride shows a copper content (Cu) of 59.09%. (Hermeleia vastatriæ). This percentage of copper content, a close approximation Black rot (Corticium 2???? ------to the theoretical, has never before been achieved, even for 30 ???ero???). the laboratory reagent quality of this compound. The Antisprayag. leaf-fall or tonic 7 2. ordinary commercial quality shows a maximum copper Onion.------Downyospor-sciteederi). Mniidew (Pere- 2 ------content of 57.5%. Size analysis of our product shows Peach------Leafcurl (Taphrina ------that 66% of the particles thereof are below three microns. deformania??s). These two results were obtained from micronised tri Brownfructigena), rot (Sclerotinia 8------basic copper chloride manufactured in the reactor using an Shotporii bole în carpophilum).(Clasieros ? ------annonium catalyst (Eq. 4). Using Sodium carbonate as ???????S------Early blight (Alternatics 3 - || ------soºa?). a catalyst (Eq. 2), we have evidence that the percentage Late blight (Phytophthora 45 ------of particles of a size below three microns is much greater. iimfestams). Rubber------Phytophthora leaf-fall.--- ? ------It has already been recognised, when proposing the use 40 Tea------Blister blight (Eacobasi- 6 10-15 of copper oxychloride as a fungicide in agriculture, that digg??2 ?6?aînS) . the smaller the particle size of this compound of copper Blackinyisan). rot (Corticitm 4. 50-350 the greater would be its fungicidal activity in addition to Redparasilicºs). rist (Cephaerºs 2???? ------its greater covering power. Constant research finally Tobacco------Downy mildey or bule 6 ------showed that this theoretical desiderata was possible in prac moid (Perenospora tabacina). tice and the copper oxychloride manufactured according Frog-eye (Cercospora 4 to our invention, specifically for use as an agricultural filicotianae). Wildfire (Pseudomonas 4. fungicide, admirably fulfills all the desired requirements tabaci}. of extremely small particle size, maximum covering power Aligular leaf spot (Pseu- 4. and high fungicidal activity. doinonas angulata.). Brownlongipes). spot (Alternaria 45 ------Laboratory tests clearly indicate that the product of this Tomatoes------Early blight (4 tierraria 3------invention is of extreme fineness and, in addition to its 8olat??i). greater and more uniform covering power, it has not been Late blight (Phytophthora 3-4------infesiams) found to cause blockage of nozzles during spraying. In Vines------Downy mildew (Plasmo- ??-? ------our carefully prepared formulations we use adhesives to 5 5 para viticola). give adequate sticking power. In addition to this, further Alla fingoEthrachose loghagiàn). (Cleosporium 28 ------adhesion is also secured in Microcop itself, since its mi Bacterial blight (Erwinia ------Cronised fineness renders it very resistant to the heaviest ????????). rainfall when applied to foliage. it will be evident from Ounces water. the foregoing that less Microcop need be applied than the 60 normal recommended dose. The powder is harmless to handle and it is completely The world's most effective fungicide non-toxic to personnel employed on spraying or to foliage. Microcop is a wettable powder containing not less than place.it will retain its effectiveness indefinitely if stored in a dry 50% of metallic copper in the form of our Microcop cop 65 Fungicide of this invention can be mixed with lead per oxychloride, CuCl2.3Cu(OH)2, Microcop is a con arhenate, calcium arsenate, rotenone, pyrethrum, DDT, centrated fungicide which man be mixed with dusts and BHC, chlordane, Toxaphene, parathion, Malathion, al which, on the mere addition of water, results in a ready drin, dieldrin, sulphur, lime and winter oils. for-use spray effective against a variety of plant diseases it is also compatible with summer oils and nicotine but affecting tea, coffee, rubber, grapevine, tomatoes, potatoes, 70 care must be taken in the formulation of any such mix tobacco, etc. Its extremely fine micronised particle size treS. and the incorporation of suitable spreading and adhesive It is not compatible with tar oils, lime-sulphur, or fluo agents, ensure uniform coverage, high fungicidal activity silicates. and marked resistance to rainfall, even under the most Having now particularly described and ascertained the severe conditions. 5 invention in the foregoing specification what we claim is: 8,202,478 1. Process of preparing micronised tribasic copper metallic copper containing copper chloride solution, ra chloride comprising treating tribasic copper chloride with pidly bubbling an excess of hot air at about 80° C. there hydrochloric acid in accordance with the following reac through, whereby tribasic copper chloride is formed in tion: Suspension in the solution according to the following re CuCl23Cu(OH)2-6HCl->4CuCl2-6H2O action: to form copper chloride, adding water to the copper chlo ride so formed to obtain a solution thereof, bringing the at least 66% of said tribasic copper chloride having an said solution of copper chloride in contact with metallic average particle size below 3 microns and when the re copper and bubbling air through the solution having me action according to the last stated equation has practically tallic copper in contact therewith, and while the air is being ceased, sodium carbonate solution is added in excess to bubbled adding 0.05 to 0.1% based on the total quantity immediately precipitate the remainder of copper chloride of copper chloride present in the liquor to be treated, of as tribasic copper chloride. a basic catalyst selected from the group consisting of so 4. Process of preparing micronised tribasic copper dium carbonate, sodium hydroxide, ammonia, ammonium chloride comprising treating tribasic copper chloride with carbonate and urea, to the metallic copper containing copper chloride solution, rapidly bubbling a large excess hydrochloric acid in accordance with the following re of hot air at about 80° C. therethrough, whereby mi action: ?- cronised tribasic copper chloride is formed in suspension CuCl2:3Cu(OH)--6HCl- > 4CuCl2--6H2O in the solution according to the following reaction: to form copper chloride, adding water to the copper chlo 20 ride so formed to obtain a solution thereof, bringing the said solution of copper chloride in contact with metallic at least 66% of said tribasic copper chloride having an copper and bubbling air through the solution having me average particle size below 3 microns. tallic copper in contact therewith and while the air is 2. Process of preparing micronised tribasic copper being bubbled adding a basic catalyst selected from the chloride comprising treating tribasic copper chloride with 25 group consisting of ammonia, ammonium hydroxide, am hydrochloric acid in accordance with the following reac monium carbonate and urea to the metallic copper con tion: taining copper chloride solution, rapidly bubbling a large excess of hot air at about 80° C. therethrough, whereby micronised tribasic copper chloride is formed in suspen to form copper chloride, adding water to the copper chlo 30 sion in the solution according to the following reaction: ride, so formed to obtain a solution thereof, stacking the ratio of the height of stacked metallic copper within the 4CuCl2 +12H2O+6O2+12Cu->4(CuCl2:3Cu(OH)al liquor to its height above the liquor being about 1:1.8 to at least 66% of said tribasic copper chloride having an about 1:2, air through the liquor having metallic copper average particle size below 3 microns. in contact therewith for some time and while it is still being bubbled, adding a basic catalyst selected from the References Cited by the Examiner group consisting of sodium carbonate, sodium hydroxide, - UNITED STATES PATENTS ammonia, ammonium carbonate and urea, to the metallic copper containing copper chloride solution, rapidly bub 1,100,675 - 6/14 Hackl ------23-97???? X 40 937?046?2 7/36 Curtin ------23-97 X bling an excess of hot air at about 80 C. therethrough, 2,104,754 1/38 Marsh et al. ------23---97-?? X whereby tribasic copper chloride is formed in suspension 2,162,091 6/39 Kuss –––------23-85 in the solution according to the following reaction: 928?201?2 5/40 SOuviron ------: 23-85 3 ? 55 4319 5/51 . Ayers ??? ?? - ? ------23-85 at least 66% of said tribasic copper chloride having an 2,777,791 1/57 Visor ------167-16 average particle size below 3 microns. 2,923,655 2/60 Vesterman ------167-16 3. Process of preparing micronised tribasic copper chloride comprising treating tribasic copper chloride with FOREIGN PATENTS hydrochloric acid in accordance with the following reac 881,578 1/43 - France... - - 50 323,115 12/29 Great Britain. tion: 480,697. 2/38 Great Britain. to form copper choride, adding water to the copper chlo OTHER REFERENCES ride so formed to obtain a solution thereof, bringing the Hanna's Handbook of Agricultural Chemicals, pages 11, said strong solution of copper chloride in contact with 5 5 12, 14, 18, 168 (2nd Ed. 1958), published by L. W. metallic copper and bubbling air through the solution hav Hanna, Forest Grove, Oreg. ing metallic copper in contact therewith, and while the air is being bubbled, adding a basic catalyst selected from MAURICEA. BRINDISI, Primary Examiner. the group consisting of sodium carbonate, sodium hy MORRIS O. WOLK, GEORGE D. MITCHELL, droxide, ammonia, ammonium carbonate and urea, to the 60 Examiners.