Патент USA US2131519код для вставки
Patented Sept. 27, 1938 TUNITEDSTATES , PAT "2,131,519 * vi'QFFIcE * ‘ 7 METHOD OF REFINING CRACKED on. B USING METALLIC SO APS OF‘ NAPHTHENIO ' ACID Masakichi Mizuta, >Marunouchi, Kojimachi-ku, Tokyo, and Teiji Yoshimura, Okubo, K'ashi wazaki-machi, Kariha-gun, Niigata-ken, Japan, assignors to :NipponSekiyu Kabushiki Kaisha, Tokyo, Japan, a corporation of Japan ' No Drawing. Original application August 11, 1934, Serial No. 739,500. Divided and this ap- - plication Aprilv 13, 1937, SerialNo. ‘136,687 1 Claim. (01. 196—’30) The present invention is a division of our co pending application which has matured into Pat ent 2,080,087 May 11, 1937, and relates to aymethod of re?ning cracked oil, characterized in that by :31 adding to cracked oil at the ordinary temperature or below it one or more of copper, lead, zinc and iron salts of naphthenic acid in solid state or as dissolved in one or mixture of two or more of gasoline, petroleum, benzol, toluol, xylols, or tur pentine, all the compounds of oiiensive odor and other impurities contained in cracked oil may not only be combined with metal or metals in dis solved state and be precipitated as insoluble salts together with the compounds of offensive odor, 15 but also even disagreeable smell compounds very di?icult to react may be adsorbed and precipitated at the same time. The object thereof is to bring all of principal sources of offensive odor such as thioalcohols con tained in cracked oil into intimate contact at a comparatively low temperature with metallic salts of organic acids soluble in cracked oil, to make them react upon each other directly by double decomposition and precipitate as insoluble salts, and at the same time to make compounds, which are very vdifficult to react with ordinary re?ning agents, such as disulphides deposited by the as tringent and adsorptive actions of these insol uble salts at the moment of their formation, thus 30 removing these sources of disagreeable odor com pletely from cracked oil without any operation detrimental to volatile oil, such as agitation, stir ring, etc. This invention relates to a method of re?ning the cracked oil produced by the cracking process of petroleum oils, the tars manufactured from coal and shale, and other organic matters and is adapted mainly for removing completely the bad smell compounds contained in cracked oil and at 40 the same time for increasing the stability of the product. The bad smell sources in cracked oil are chie?y thioalcohols, di-sulphides and unsaturated or ganic compounds, above all, low boiling thioalco 45 hols. These substances even in the slightest quantity can give offensive smell to volatile oil. For instance, ethyl thiolacohol can still give dis agreeable smell to gasoline even with the con centration M0000 or tioo 000 by weight. Thioalcohol gives out offensive smell lesser 50 with the increase of its molecular weight, but even crystallizable higher member of thioalcohol has bad smell, and thioalcohol is liable to reduce its reactive power gradually with the increase of 55 its molecular weight. In cracked oil, the quantity of disulphide orig inally present in it is only very small, the ma jority being produced by the oxidation from thio alcohol and consequently its quantity increases gradually with the lapse of time after the manu facture of cracked oil. This compound is also the cause for giving a kind of burning smell to cracked oil. It is extremely difficult to react'wlth ordinary re?ning agents for cracked oil and con sequently is dif?cult to remove. Some unsaturated . -_ organic compounds in If isolated, they ’ cracked oil are very unstable. will mostly polymerize at once, but if diluted with gasoline, they will become comparatively more’ stable. They give a kind of disagreeable odor to 15 crack-ed oil by their oxidation products. However, they may be removed easily by treatment. with sulphuric acid. ' I ' _ Now, according to the present method which is the result of the study of the constitutions and 20 properties of many such bad smell compounds, these bad smell sources may be removed com pletely. The known methods all employ re?ning agents insoluble in the object to be puri?ed, so that even by any violent agitation the intimate con tact of a re?ning agent with the object to be puri?ed is difficult, more so when their difference in the speci?c gravity is greater. Therefore, only a portion, but not the whole, of these bad smell 30 compounds are removed and consequently the complete removing of the bad smell source can not be expected. In the re?ning operation, the oxidation of thioalcohols is accelerated more and more with the violency of agitation in the atmos 35 phere and therefore this agitation operation does not only make thioalcohols stay as disulphides, but also causes the loss of gasoline due to volatiliza tion and consequently the decrease of the yield 40 of the product. The inventors have isolated various kinds of thioalcohols from cracked oil and manufactured various kinds of disulphides therefrom, and then studied their reactions with various kinds of met als and metallic salts of organic and inorganic 45 acids and their various properties including solu bilities, stabilities etc. Also they have studied the easiness and speed of the formation of me tallic salts from the solutions of thioalcohols and disulphides in petroleum hydrocarbons, and'the 50 behavior of these salts in petroleum hydrocarbons. Thus, by applying the results of these studies to cracked oil and studying the best condition with regard to the re?ning of cracked oil, they have succeeded in discovering the following matters:— 55 2,131,519 1. One or mixture of copper, lead, zinc and iron salts of naphthenic acid are easily soluble in which is prepared by settling and ?ltering a solu tion of 200 kilograms of copper naphthenate in gasoline, petroleum oil, benzol, toluol, xylols, tur 500 litres of gasoline, to the above cracked oll pentine, etc., and, when kept as concentrated puri?ed- by alkali solution and leave the mixture solutions, they do not change their ‘qualities. for 8 to 12 hours to settle down insoluble salts 2. If a solution of metallic salts of these or- ~ produced, after which the supernatant oil is ganic acids is added to gasoline or petroleum oils ?ltered through fuller’s earth ?ltering bed. Next, containing thioalcohols, it disperses throughout subject the ?ltrated oil to steam distillation in a the latter spontaneously, mixes with it and reacts steam still and distill o? the gasoline fraction. 10 with thioalcohols by double decomposition even Put the gasoline fraction in a continuous treat 10 at the ordinary temperature or below it, deposit ing apparatus and wash it with sulphuric acid, ing metallic salts of thioalcohols. Thus, by this alkali and water by turns. The ?nished gasoline way it is possible to remove thioalcohols complete thus produced has an excellent quality free from ly from the oil. disagreeable odor. 15 3. Disulphide produced here is mostly adsorbed Thus, it may be possible to obtain gasoline of into metallic salt of thioalcohol the instant it superior quality which is not only free from dis 15 is produced and is deposited with salt if the agreeable smell, but also has very great stability. product is allowed to be settled spontaneously This invention as stated above has the follow without stirring and presents the appearance as ing advantages:— 20 if this re?ning reaction had occurred according 1. As a re?ning agent is brought into very inti 20 to only the Equation 1. . 4. It is necessary that the reaction between metallic salt of organic acid and thioalcohol should proceed slowly. . Thus, after the comple 25 tion of the reaction and the deposition of metallic salt of thioalcohol and disulphide, the super natant oil is ?ltered gently through fuller’s earth ?ltering bed and thus these bad smell sources may be separated from the oil to be puri?ed com 30 pletely. 5. The re?ned cracked oil may be subjected to steam distillation directly. After the part of gas oline fraction is distilled, the residual oil is stirred with alkali solution and thus naphthenic acid 35 may be recovered as alkali soap from the oil. When the result of the above study was applied to the re?ning of cracked oil, it was possible to produce cracked gasoline entirely free from thio alcohols and the bad smell of disulphides. 40 The following are a few examples of re?ning of cracked oil for the preparation of cracked gasoline:Add 0.5% (by volume) of 20% caustic soda solution to 100 kilolitres of the cracked oil pro 45 duced from Dubb’s cracking plant and agitate it to remove sulphuretted hydrogen, organic acids and other reactive substances from the cracked oil. This pre-treatment economizes metallic salt of organic acid to be required. Next, after wash ing it with water enough to remove alkali-residue completely, dehydrate it. Then, add clear ex tract solution of copper naphthenate in gasoline, mate contact with the object to be re?ned easily, it can react with the whole of bad smell sources of cracked oil, ' 2. It is possible not only to remove disulphides produced during the reaction of this re?ning, but also to remove disulphides originally contained in the object to be re?ned by astringent and ad- _ sorptive actions. 3. For the above reason, bad smell sources can be removed completely from cracked oil. 30 4. As the object to be puri?ed is not stirred or agitated, it is possible to prevent the oxida tion of thioalcohols and also minimize the vapori zation loss of the volatile portion of the object to be re?ned. 35 5. The recovery of re?ning agent is easy. We claim: ~ The method of re?ning cracked oil, which con sists in dissolving oil-soluble heavy metallic soap of naphthenic acid in a volatile organic solvent 40 which will disperse homogeneously in cracked oil; pouring the solution thus obtained slowly into cracked oil while in a cold state to cause same to disperse naturally and homogeneously without heating or stirring in the cracked oil whereby 45 same will react with the intermingling mercap tans and precipitate same by double decomposi tion as insoluble metallic salts; separating the precipitate; and distilling the remaining liquor to separate it from the organic solvent. MASAKICHI MIZUTA. TEIJI YOSHIMURAA.