Document wBOxzqbjBZkGyGbE56GK3ZGB

Th e SfiERWfjt'WiLiiAMs Co. In t e r -Of f ic e Le t t e r FOR Cleveland Mr . F. W. Porter ANIWCAINO LETTER OF il Pk o m i Coffeyville OFFICE OFFICE F*'Vi. ? oci* DAT* October 9, 1935 SUBJECT Booklet Information DICTATED BY ^*4 ant. * The following .are /ihe manufacturing procedures for leaded zinc, zinc sulfide, and zinc sulfate, which you have requested. . t " ' Leaded Zinc * 111 y* "P 1 ,l111 11 OaloJLeaded zinc pigments are manufactured from the highest grade lead and zinc ores available. As these oresvcome from the mines, they first undergo a crushing operation. They are then concentrated either-by oil flotation, in jigs,-on shaking tables or by. electrostatic aepar^ibn.* s - ^ ^^ , The cleaja concentrates, upon arrival at the plant are sampled -for chemicalanalysisani^ in storage' bins according to their The zinc sulfide ores from this districtjf-calied^ilib-blende, assay about 60J6 of zinc and 2 pfrleadf4whJle|;^ '' iores, known as galena, iassa^lbnliffiga^^ lead land 1% of zinc. The remaining:portibh^f|the8e.rores consists w' 'S'.. mainly of the sulfur with whichttheSmetalst^ -- *. -. * r . * .^.Theiiie^ste^s^oiRjF^jli^^^^lM10-2^ ores, a sort of refining"process ,t*hayi3^^'as''^it,s'|gurpose# the removal of the sulfur content! ' This^sulfur fis driven off at a red heat in huge, automaticallyI operated roasters leavingrthe zinc in the form;of the oxide U > - ` 'V The lead sulfide (galena) ores are not given, this roasting. The sulfur content of- these is ultimately oxidized to the basic sulfate in the furnace-operations . described below. It is in this furnace processingjthat the finished pigment, is made.'--,*-- In preparing the furnace charge or mix ths proper blending of the lead ores with the roasted zinc ores and these in turn with the other ingredients of the charge, such as chatty, coal, and flux, is of very great importance. Upon it depends the ratio of zinc oxide to basic lead sulfate in the finished pigment. Likewise the color and other important qualities of the final product are largely determined at this point. , '' 0007-svip-ooooo7i2i 1 't Ai f ' -- iv * v. * 2- - From the mixers the charge is fed to the furnaces and ignited. The intense heat from the burning of the coal causes various chemical reactions to take place and as a result lead.and zinc vapors are formed which rise from the charge to enter what is known as the combustion chamber. Here the vapors, burned by the admittance of air, form rolling white clouds of the very finely divided basic lead sulfate and zinc oxide particles which together constitute Ozlo Leaded Zinc. The lead and zinc components fumed together, as they are, become bonded in a form highly desirable, especially from a standpoint of durability. As the pigment passes from the combustion chamber it is conducted, in a steady .stream of floating particles, through^long cooling lines, to the collecting system. Here it is caused to enter cotton bags standing upright over hoppers. The pigment particles are retained on the inner,,walls of the bags while the furnace gases pass out through the meshes of the cloth. At regular intervals the bagsj*iare ! shaken, causing the pigment to fallto thehoppers sbelow from iridch it is drawn and filled into bags for; snipping. The following table lists the uses and characteristicsIbf^OzlblLeadedl-Zinc Pigments. V ' .Zr.% -`J :.v - Oil Absorption . Gardner-Coleman ^ ^ Ratio Average ' Method (Zinc jQxide to Specific Residue (gms. Oil per 100 Grade Basic Lead Sulfate) Gravity on 325 Mesh gms. Pigment) 412 1526 65/35 60/40 so/ xi 5.92 5.94 0.025/S 0.025? 17.0 - 19.0 16.0 - 18.0 Uses 412 1526 Paints Paints 0007-SWP-000007122 -3 - Zinc ^Sulfide .When the water solution of a zinc salt is mixed . with the water solution of a sulfide a chemical reaction takes place which results in the precipitation of zinc sulfide as a very finely divided white solid. It is by this precipitation process, from highly purified solutions, that zinc sulfide is given its first form in this plant. The "crude" zinc sulfide thus produced is then carefully washed free of the reaction liquor. This is followed by drying preparatory to calcination. The purpose of the calcining operation is one of altering the physical characteristics in such a way as to best develop whiteness of color, high opacity, proper oil absorption and desirhble texture. This is accomplished by careful heating under highly controlled atmospheric conditions-followed by water quenching.. Lumps of pigment formed by these operations are completely broken iUp by wet milling leaving the zinc sulfide -partieles ^very.;3Pi2ielyrdiidae^in.' waters suspension. 4 The next;.stew.:theubulkof the water pigment is :, carefullydried'at l<nr^i^]*at^d<^t^roue$3y disinte- grated and packedJinto bags^Madyjlor /shipment. CrBelowlare given characteristics and uses of our Zinc Sulfide Pigments- ;v Grade - -- '. Gravity on 325 Mesh Oil Absorption Gardner-Coleman Method (gm Oil per 100 gms. Pigment) "A" 4.00 Max. - 0.3! 28.0 - 30.0 Uses Pigment in - Faints, Oil Cloths, Linoleum, Leather. In the manufacture of white and-opaque glass. 0007-SWP-000007123 Zinc Sulfate Zinc Sulfate, also known as white vitriol, is manufactured at Coffeyville from the same, prime quality, * zinc sulfide ores as are;used in making Ozlo Leaded Zinc Pigments. \ As the zinc, invthis instance, is extracted by a leaching process it is highly desirable that the ore be reduced to as small a particle size, as is practical, in keeping with other conditions. This is accomplished by a grinding and screening operation. The ground ore is then roasted in much the same manner and to the same end as is the zinc ore which is taken for use in the manufacture of leaded zinc pigment. This roasted ore is subsequently filled into suitably designed leaching tanks where it is treated with dilute sulfuric acid. The acid reacts chemically with the zinc oxide in the roasted ore resulting in the making of a dilute zinc sulfate solution. Since just enough . sulfuric acid is used with a batch of ore to react with the zinc oxide present\ the leaching process ends at a point where both, acid and oxide are entirely used up. - - This zinc sulfate solution is clarified by settling.andjfiltering. It is-then punmed through a purifjringisystem where any traces of, soluble impurities are carefiilly^empved. . - - .. ' The.purified liquor is then run into evaporating tanks^-idie]^^tM;|ii>xees8 water; is driven off by heating. The|rsulting,y concentrated solution is either run off ihtdicrystallizing pans where that grade of solid zinc sulfate| containing five moles of water and 25i# of zinc, is obtained by;crystallization, or it is subjected to high temperatures in a dehydration process .to produce the one mole salt vhich contains 36/6 of zinc. . Finally, both grades are ground, screened and packed into bags or barrels* ready for the trade. In the table, which follows, the uses and char acteristics, of these two grades of zinc sulfate are given. 0007-SWP -000007124 Grad Zinc Metal Content Fineness One Mole 36/S Thru 7 Mesh Five Mole 25i% Thru 7 Mesh Uses of Zinc Sulfate Manufacture of lithopone. Mordant in printing and dyeing. Agent in removal of sulfur compounds from gasoline.. Preservative and clarifying agent for glue solutions. In the chemical industry as a precipitant of contaminating sulfides in certain processes. Preservative of wood and skins. Agent in the treating of soils. Disinfectant. Differential flotation of minerals. Rayon manufacture. Yours very truly. CEP:RK 0007-SWP-000007125