tile ainount contained in the mixer, added to the oil in the inixer ' and blended there%vith until the mixture is of a creamy consistency and free from lumps-. If the oil is very beavy it ii-iay I)e heated gently, up to S',I@, 100' F., to promote mixing. The mixtiire is iiow allowe(I to stand quietly, o@ ii,ith verv gentle i'otatiod of the agititing I)addles, i iiitil air ceises to come to the siir10 face, %vhicli iiqtiallv i@eqL[ii-es several liours. The oil in the still now being l@ot and the steaiii jets iii , tetioii, the pun-ip S is starte(I a-i(I the tii--fi-ee adsorbetit mixttii-e pumped iiito the still. If the adsorbent 15 ilse@T is free fi-oiti @",ater the mixttire rnav I)e@ pumped in as fast as d6sired . : ,' but if it coiitains mucli -%v,.iter the I)tiinp speed should be so re,(rulated that the evoliition of steaiii taking place -,ihen the -%v@et clay falls into 20 the hot oil ivill iiot ovei@load the v,,ipor vent and throw too nitich back pressiire onto the still. If a,-iy reasonable care is taken in this regard it ivill be fotind verv easy to pump in inixtures coiitainln,- considerable -%vater -without frothing or biimpiilg of the coiite-iits of the still, but c,@ire should be taken not to cool the coiitents of the still toa ftr while pumpiiig in the absorbent mixture, as below 3500 Fabr. frotbin(v is like2,) ly to occur. The oil-a(isorbent mixttire being all pumped in, tgitatioii and stean-iin(r are I continiied Lili'il no f Lirther reduction iri (Tepth of color of oil, ,is determined by filteriljcr n5 m and comparin(r small sainples draivii from the still can n be observed and also uiitil such samples bave no cracked or offensive odor. Ustiallv the maximum color ettect will be attaine' d in abo Lit half -,in hour, and 40 freedoin from odor in an hour or less, after the last of the adsorbelit i-i-iixture is pumped in thougli fhese tiiiies will be coiitrolled to some extent by the sizes of the batch and by the propoi-tion of adsorbent added, large 45 batches and heavy doses of adsorbent requiring longer treatinent than is li,,,ro in(licated. When it is observed tl-iat the rea(,tion is coinplete and the product thorou@hly q-weetr)o eiied, the oil is witlidrawn from the -still through a cooling coil, iii the maianer commolily prai:@ticed in pumring out still bottoms, or in other convenient manner, and tllereafter the suspended solid adsorbent sepli-ated from the treated oil by filter-pressing or centrifuging or other of the weR l,inown nieans for separatin& liquids froiii solids. This process may be applied with particu1,Lr advantage to the purification of -such reduced oils as the so-called steam refined cylinder oils, as these oils while in process of reduction are already at the proper temperaiure for treat,-nent. In this applicaC,5 tion of my invention the oscillating paddles E-E may be fitted into the reducirz stills, or-they may be dispensed with and tl@'e Lisual,. bottom steam used for agitation. The mixture of adsorbent with a portion of the nonreduced oil, or -vvith a portion of reduced oil 70 from a previous batch, is prepared as above described and tli-e air allowed to separate. This iiiixtiire is then pum'ped into the -still - in wliicli tlio oil is being reduced at some suitabli3 stage in the distillation, preferably 75 near the end of the run. and befotp- the still contents ai-e- graded. The redlictionis then finish@@,d in the ii@ual manner,-the con-@ents of the sti-11 tested for viscosity or flash test or what6ver property is fixed.in advance 80 a-, determi ng -the fin of the-run and isb 9 after pum ing out the still conteiits the spent adsor ent is separated from the purified oil by fi tration or other convenient maniier. As reducing runs are always ma;de with S5 steam in the still, all the requisites of this process, that is to say, the exclusion of air, the niaiiitenance of the highest temperature on the oil, a'nd, the steaming @ofF of 'aiiy deprovided without 90 ry proc6ss of reara on ,ind adent mixture and the separation from the oil of the spent adsorbent. 95 H:ivin- tlius described the inventio . n, what is claim@-d as new and desired to be protected I)y Letters Patent, is1. The metliod of purifyiiig and Ra@tIy decoloi-izing oil, which consists i n iilixincy loo with a portion of the oil to be, d-ecolorize-d a powdered porous' adsorbent material, althe niixture to rest until the ,)ir bis 'Owin@'is been placed from the pores of the adsorbent by the oil intermixed therewith, then 1LI5 heat ng the remainder of the oil to a temperature above 350' F. and inter]-nixing tberewitli the above said mixture of oil and adsorbent, to permit the adsorbent to withdraw coloring matter from the oil,. and 110 finalIV s6parating the spent adsorbe-.lt witli its cintained coloriiia m,,itter from the decolorized oil by me@b-anical means. 2. The method of purifyin- and partly consists 115 decolorizing oils --wliieh in mixing -with a portion of the oil to be decolorized a powdered porous adsorbent material, allowing the mixture to rest iintil the -,iir @as beeii displaced from the pores of the adsorbent by the oil intermixed therewith, then heat- 120 iiig the remainder of the oil to a temperature above 350' F. and deliverilag onto the body of the heated oil a relatively small stream. of the above said mixture for inteimixinowith the body of hot oil, the temperature 125 of the oil body being maintaiiied during the period of delivery of stich mixture, and flaally selar"ting the spent adsorberit from the Puri ed oil by mechanical mealis. 3 The methocl of.purifying and partly 130

decolorizing oils, which consists ill mixiiig ivith a portion of the oil to be decolorized a poivdered porous adsorbent mater@@al, allowilithe iiiixture to rest until the --iir has been displaced froiii the pores of the adsorbent by the oil intermixed therewith, th'en lieating the reinainder of the oil to a teinperattire above 350' F., and deliverinu into the body of 'hot oil a relatively siiiall s-treajn of the above said inixttire, vigoi@ously ,gitating tlie, body of liot oil al-id inailitaiiiiii(, its temperature during the period cl' - stich delivery to permit the adsorbent to -vvithdi-aw coloi-in, iiiatter from the 1-iot oil, and finaII37 sepai-@tina the spent adsorbeiit with its contained coloviiig matter 'Lrom i:he decolorized oil by ineebanicil means. 4. The iiiethod of purifyiiig ancl Ra4ty decoloi-iziiio- oils which consists in mixing witli a portion of the oil to be decolorized t poivdered porous adsorbent material, alun lowil-ig the inixture to rest til the air has beeii displaced fron-i the pores of the adsorbeiit by the oil intermixed therewith, then iiiixing the above said oil adsorbeiit illixture 25 witli the i-eniainde.r of th.e oil to be decolorized, heatiiig this iiiixture to ,t temI)el-ature tbove i'@i-)Oo F., ,tjid finally separating the spent I dsorbeiit froin the decolorized 11 oil by iiiecliaiiical meain@. 30 In testimony whereof I have signed my nime to this specification. P-A-UL W. PRUTZMAN.

Patented Nov. 17, 1925. l@561'999 UNITED STATES PATENT OFFICE, PAUL W. PRUTZMAN, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO GENERAL PR-. TROLEUM CORPOP.ATION, OF LOS ANGELES, CALIFORNIA, A CORPORATION OF CALIFORNIA. XETHOD OF TREATIN.G OILS. Application filed September To all whoi@z it 97-bccy co,?Wer-n: Be it Ifnown that I, PAUL W. PRUTZI.[A-N, a citizen of the United States, residing at. Los Angeles, in the coiinty of los Angeles and -State of Califoriaia, have invented certaiii neW and useful Improvements in Metliods of Treating Oils, of which the following is a specification. ' I The present iiivention relates to.a me-thod 10 for purifyin(,@ and decolorizing pefroleum oi-is and petr6leum products of high boiling poiiat, at a lower cost and with greater, facility than has heretofore been possible under the pre.sent methods for the treatment 15 fhereof. In the carrying out of my M'ethod invention the following steps are resorted to, viz:-the oil to be treated is heated to a tein@erature in excess of 3500 F. alid @refer20 ably close to the boiling poiiit of the oil, iii a closed vessel from whicli air is removed and excluded in so fai- as possible; to the oil is added @n sufficieiit quantity in Ldsorbent such as fiiiely ground fuller's eartli, bone25 blael-, or the residue from the acid treatn-ient of mqiitmorillonite as hereinafter described, or other suitable clecolorizing and purifying agent in such a manner as to preveint the admission of oxygen or air to the heated oil; 3o allowin- the de(@olorizing age@t to react under such coiaditions as to minimize und6sirable secondary-@'reactions ' and finally agit-,tting the cooling ii-iass with steam or other nonreactive gas or vapor until all volat-ile 35 secoiidary products areeli'minated. The first two steps of the meth6d may be carried out at the sime time or even reverse in order without serious affecting the final results, although I prel@er to appiy them seriatum 46 and in the order given, both as a matter , of co.-ivenience and b'ecause better results may be- o'btained. The rnaterials which may bo, profitably purified and . p:irtly deco@oiized by the 45 present -method invention include all petk4:)leum products boiling above,,350" ,F. which in commercial terms include hea VY bu.rning oils, lubricating oils, pa-raffin o medicinal oils, solid paraffin wax, petrol 50 and cylinder oils. However, some of the animal and vegetable fats and *axes may be advantageously treated under this method, but it is not suited to the purification of edible oils and similar p'roducts where the 2, 1922. S@tial.N6. 586,030. t aste or flavarl6f the finislied product is a 5 5 c onsiderat on. Iii carrying out my iiivention tecourse is h ad to a-group or class of artificial produ cts prepared by acid treatment Gf certain c lay_like niiiierals, which products when 6 o p roperly prepared have the property of ads orbing'and r6moving very large proportions o f impurities and colo:@ing matters from oils a t moderate.temperatures, and of removing ii lcreasingly larger proportions 'at increas6 5 i ngly elevated temperatures. -IV'hen the mine-ral montmorillonite, locally. k nown as otaylite and found in San Diego County, California; or the, mineral known as Dea-th Valley clay, and found in certain '70 parts of.Califdr'nia and Nevada; or the well known mineral bauxite,; is treated with a considerable ptoportion, up to half its original weigilt, of sulfuric acid, and the acid allowed to completely react with the mineral, '75 and@ the remainder "if anv of the acid and the soltibl ' e products of tfie reaction washed a-way by washidg with Water, a -waterinsoluble residue remains. This treatinent radicary modifies the materials. As a niat- so ter of fact, the acid treatil@elat is directed to the modification of the material for the purpo se of producing from a raw material, wh ich has no appreciable decolorizing value, a finished material which has a high . de- 85 col orizing value. The yield of residue on' this treatment is between 75 and 807'o of th6 net clay taken when such'treatment is appli ed,io materials of the montmo' rillonite cla ss, which includes montinorillonite i:)roper 90 'an d the so-called Death Valley clay.- The fini shed miterial as produced under my.inve ntion has an - extremely higli decolorizing val ue, whereas in its natural state the ma teri al acted upon has little, if alay, decoloriz- 95 ing va-lue. The residues so prepated fro'm either of the se and from similar rainerals are readily re duced to a powder when dry or partially dr y, and in such condition have th6 property 100 of adsorbin- many of the impurities occurrin g in miin.@ral.o;ls, and as these iinpurities are thus fixed iii the'pores of the'miner@l po wder they m4.y b6 removed from the oil by filteriift- or settlin-- out the powder. -This @105 property @f adsorbii;i impurities and coloriiig matteils is greatly enhanced by heating the oil durina the application of 'the mineral

1,561,999 residue, and to such an extent that in a typical case, where the residue froina the mineral montrnorillonit -e -was al)plied to a steam refined cylinder oil at various temperatures, the work done by unit we-ight at diltereint temperatures ivas in the followin(r proportion:-at 2001 Falir. ' 1.00 unit of work- at 3000 Fahr., 3.33 units; at 400' 14'ahr.' ' 4.'i 0 units: at 500' Fi ahr.,'10.50 tinits; 10 and at 600' Fahr., 16.00 units. The savin(y resulting from thus inereasi-ng the efficiene.@ of the adsorbent is very iniportant, as it means not merely the redtic-, tioii in quantity of expensive ad orbent 1.5 used, but al-so proportionall.)r reduces the quantity of oil carried away 4nd lost in removing the adsorbent from the oil, and also the cost 'of the phy.sical operation of removing the adsorbent, as by filtering 20 However, the real value of this saving in cost will not be realized unless pre6autions are taken to avoid or neutralize certain seeondary reactions incident to the use of powdered adsorbents at high temperatures, for 25 if such precautions are omitt@d the deprecia.tion in quality 6f ti-le oi.1 may be so (rreat as to entirely offset the savin- eifecte5, or even to el'itirely de-s,troy tl-io commercial value of the final product. These second'O ary reactions are:-oxidatioii of the oil by oxygen admitted -with or duriiig th -e addition of the adsorbent; and cracking or heat decomposition of the oil incited by a fixed property of this class of adsorbent mate15 rials. It i-s well known that oxidation takes place readily Ni@lien petroleum oils are brought int6 contact with atmosplieric.aii- at terhperatures mitch above 150' F., an& is aecelerat,ed by Iiiglier temperatures and, by 40 the presence of po@vdered adsorbent matei-ials wliieh appear to act as carriers. It is ,tlso stron ly promoted by introdticing -.iir belo-w the surface of the heated oil, and by finely subdividiii- the air bubbles, as by 45 these means the surf-,ice of contact is increased. Oxidation darl-@,ens -the color of oils, gives them a characteristic and -Linpleasant odor, and produees a. blue outertone or fluores50 ce ce which- is disa reeable to the eye, so n 9 that tbis' reaction is in every. way undesirable, and if it goes too far will destroy th-valtie of the oil. In addin- powdered inaterials to oil-s at 55 high tempe@rature in clo@,zed vessels. air inay be introduced in three ways, viz,: ' accidental , as free air accon-ipanyiia- tlle cliar(Te IY zn of powder; as entrained or iliterstitial air. filling the voids betiveen the grains of the 60 compacted po,%@der, and as adsorbed ,iir, fill.ing the pores iii the (-Yraiiis of whicli the po-,vder is coiiiposed. The first iilay be avoided by proper meelianical arraiigeinents, -and the inter.-,titial air will be separated as,the 65 'powder enters the surf;tce of the hot oil liia:ss, so that it acts only on such surface and with a minimum, effect, also its quantity is not irppgrtant. But the quantity of adsorbed air is great, and as it is given off ohly slowly on wettin(r the adsorbent -%iitli oil, it 70 is carried into the liot ma-ss and there disengaged in microscopic bubbles which present an, enormous contact surface, ancl tlierefore a-re.Itiglily reactive. A potiiid of driecl iiiontmorilloi-iite residue liavin- the i-oluiiie, 75 sliaken down, of 0.023 cubic feet contaiiis about 0.172 clibic foo.t air, or 71/2 t'Imes its own voluiiie, this aii- beiii adsorbed and-litcrally compressed into the pores. of the iiiinet-al, dild capable of beiiit(,, disengage(I 50 when the miiieral is brought iilto contact witli -some liq@id ilvliieli it adsorbs iiioi-c strongly than air. In order to Avoid tlyp, detrimeiital oxidizilig effect, by removing all air f roi-n the inin- 85 eral before addin(r the latter to the oil being treated, I pi-efer to mix the adsorbent powder witli enough of the oil to f orm a fltiid or tliiekly fl'uid mass, by which mean-,-, the adsorbent is wetted by the oil, and t6 al- 90 low this fltiid mass to rest iintil' tlia air is tliorou-hly disen(,Yaged' and freed froin the inixture, condnefing this sta-el of the, operation at the lowest temperiture at which the oil is stifficiently fluid to allow the air I)tib- 1)5 bles to pass out, and ilways at a temperatuie low enough to preveiit reaction betweel'i air ajid oil. A tempera-ture of 100' F. is' usiially higli bno-Ligh to @allow the-air to escape, and at this temperature oxidation is 100 almost inappreciable. Wieli free from air the portion of oil codtaining the adsorbent is pumped into the remainder of the oil, whicli ma-y be heated eitlier beforo, or after such addition, and as the piiilip does i-iot dis- 105 charo,,e any free air info@ the oil vessel, it will @e seen that air i-sentii@ely excluded, aiid oxidation may tlius be entirely avoided. - Cracking of the heated oil c,,Lniiot be entirely avoided,, but the action may be mirii- 110 inized and the uiidesirable effect-s may be iaclitralized. When higli boiling petroleiiiii products -,ire heated to near their boiling point they often approacli the temperature at which.they begin to decompose spon- 115 taneously, and -when .i solid adsorbe-nt material is added -to an oil so lieate-d'its criticai teinperature of decoiilposition is tliereby lowered, and decompositioii -zets in. T]IO class oi mineral residues used as i-eagents 120 in this invention ai,e particularly active decompo'siiig agents becaiise of tlieii- Iiigli value as adsorbeiits. The exteiit of tlie. dec()Illl)ositiii(y reactioii, liowever, is limited by the diiration of tl-ie life of the adsoi-bent, tliai, 'Is 125 to say, the adsorl-eiit coiitin'iies to act as -,t promotor or accelerator of decompo,.gitioti only so long as its adsorptive po-%ver reillains, and wlien this is losi or satisfied I)y the ad-' sorptioii of impurities from the oil its cle. 130

C(iliposing power disappears also, and crack@ i-@ig will cease provided the -temperattire of the oil be below its critical temperature. I 1-iave disco'cred that the cracking ettect v jyiay I)c liliniiiiized by allowing the ininei-al re,,sldi.ie pi-ior to iiiixin(r witli the colct oil to i-etaiii is iiiucli @vater is is colisisterit ivitll i-educing it to a powder. Because of tllc exti-eme porosity of these residues, this proporlo tioii of ii--,ttet- is rathei- Iiioli a-iicl I liave fotind 301/'(,@ b3, weig)lit of water iii the partly (Iried residtio to be a suitable propoi@tion. 'I'l I is Avater act-s to reduce the crackingeff ect, I ,)lit it does iiot eiitirely obviate crackili,,,,. it is II ot c:@.c@el)tial to iise -Nvater for tliig I)iir1)()se, as (lie treatiiielit - Nvitli steati) AN'ill liellii,alize the I)ad i-estilts T()Ilowili(,y fr(ln (@t,acking. The i@iiidesii-able ell@,ets followiiig filom, ci,,i.ekilig iiiay be eiitii-ely neutralizect bv sititable iiiaiiipiilatioi@ of the oil duriiig ana folloivii-io- the additioii of the niiiieral ad sorbei-it."TliLis, if the adsorbent be added to a heated oil at rest, the decoliiposition 2,-,-pro,lucts, iihiell are iistitilly moi-e volatile tliaii the oil from -Nihich they are produced, AN,ill iievei-theless reiiiain dissolved in such 11, aii(I ivill iiiipart to 't an ofteiisive oclor, o -ind render it tiiistable to liglit aiid ai-i i,O lionvoyer, the oil be stroiigly agitat@od during the addition of tlle adsorbelit aiid. at the saiiie time subjec-ied to tl-ie action of steam, or soiiie otlier fixed gas or vapor, by wliieli ,t pti-tiil pressure effect is obtaiiiell, tlle presstii-es on the vapors of the cracked voltltile I)odies %vill be so loivei-ed that they will (list:il otit of tlie-niass al-id be carried away - v@-itli the :steam or gas, and thus they will Ic pirtl - v cari,ied away is foriiied, and sti@ii is a,fter the adsorbent is all ad(lecl ,,ii(I lias coiiipletecl its decolorizinu antl p.,Lirifylji,)@ actioii (iiid has becoliae sattirated iiiid lias eeased to act as a promoter of de4.-) coiiil)ositioii, iyiay be reiiio-ved by coi-itintiiiig the a(,itatioii -aiid the passa(ye of steaiu n o,@- )-as lintil the odor of decom@ositioii disZ, ing@ on -walls B which form the firebox C. 'Phe oil to be treated is pumped iiito this still, eitlier to be there heate,,I, or preferably through t preheating coil in which it is bi-ought to the desired temperature be- 7,I) foi-e entei-ilig the still. The st . ill is prbvidecl IlTitli a vapor pipe D passil-ig to a condenser iiot @lio-vvii, or if it is liot desire(I to colidense the siiiall amottilt of vapoi-s foi-li-ied, the coii(lensei- iiiay b-(@ oiilitted aii(I the still 3 x,eiite(f directly- to the air. The contents of'tlie still ai-e a,ritited by tlie, agitator E-E, Nylileli ogeillites oii the trLInniong F-F anct is actiiated by tiie craiik 0r iiyliieli iii ttirii is actuate@l by the c,,tble @D li,,iiid tlie. I)ellcranl@ 1.@ I)y the ei-aiik J-,T tiid fiiially hy the inotor K, tlirougli any sti.itable si-stem of belts or geariiig. Steaii-i is admitted to the agitator tlirougli the, pipe L, travels down the ariiis INI-M, and is fiiially discharged through the perfoi,,Ltioiis N-LN. As the pipes in .-Nvhich these perforations are located oscillate over the eiitii-e lieited surface of the, still aiid eNtencl froiii eiid to-end the entire bottom l,'O gupface of the still is'ke)pt swept cleaii aiid the adsorbent is kept evenlydistributed thro-Licrh the oil mass at all times. Good -tl)l)eai-s tiid the oil becomes perfec.tl@, saveet.' teiits of the iiiixer 0 to the still A) liv this iileans the oil iyi-.iy. be obtaii'led with @O the best possible odor, alid so free Troll, ('ec oi-tipositioi-i I)rodiiets as to be perfectly stable iii(I pel-iiiaiieiit in color. Aiiy suitable apparatiis iiiay be employe(,l foi@ the cai,rviiig otit of the iiietliod inveiitioii, the oni ilIListrated iii the accompaliyiii- driivin(, liai@iii1)'rovei-i practicable for the purpose desired and whereiiiFigtire 1 is aii end elevation of the apI)at-atus. Figure 2 is a brokei-i loligituciiiial secGo t; .oiial view cf tlie still, taken oii the Iiiie X--X Fi 1 of the drawings, and Figure 3 is a idetail vie", of the ineaiis for actuatinz the a-aitatoi- for the contents of the still. A is ali or(iinary cylindrical oil still, rest-' results liai-e also been had i-@vithout aiiy other agitation tbaii that produced by jettin- 95 steaii3. agaiiist the still botton-i from fixe(I ste,,iiii I)il)es, aiid the agitating device sliowli is a preferred method oiily. 0 is a taiik in i-vbicli the oil a,@id allsorb eiit are inixed by ihe piddles P W'hicli ai-e 100 (Ii-ii-en I)y the gearing Q fr6iii any suitable sotirce of power. R is a stealii coil for heating the coi-iteiits of tank 0 if requirel. Alitliy types of mixer ai-e suitable for this piirpose, the oiily essential requii-ement bei.i-i- tliat tlic mixtiire of oil and adsorbeiit ;hall be alloived to rest uiit'l the air is disengaged , which iiiakes continuous feed mixers unsuitable iinless provided with a i@e ivii-ig taiik. 110 ce S is a piimp for transferrii-ig the coiithrough the line T. The diseliai-o7e froiii this Iiiie iiiay be allo-%ved to fall oi-ito the liot conteiits 115 of still, o.iit iiiiy be disti-ibuted throuclyh a pet-foiate(I pipe 1-uiiiiiiig the lengtli of the still aii(I located Ibove the oil level. Tii ole,.i.-,tting this al)l)ai-attis the still A is filled witli the oil to be, treated, an@l brouglit 120 to the I)roper tei-i4peratui-e, eitlier by heatilio1,,@liile puniping iii or by Li fire iii the fire-box C. Iii c@itliei- case steain sliould be ttirned into the still at froiii i')00 to i')50' F., as is coinmoil practice in distilliilg oils, Ilid the agitator, if any is iised, shoiil(l I)e started. A stifficielit I portioii of cold oil is at the saine time puli-iped ii-ito inixer 0, anO the -juaiitity of adsorbent required for the amount of oil contained in the still -plus 11.0