CS256581B1

CS256581B1 - Method of reading waste vials from the production of N-phenyl-N-isopropyl-p-phenylenediamine

Info

Publication number: CS256581B1
Application number: CS867189A
Authority: CS
Inventors: Alois Jaros; Pavel Dolezel; Robert Seitz; Dusan Bicek; Dusan Skrada; Jan Brezovicky
Original assignee: Alois Jaros; Pavel Dolezel; Robert Seitz; Dusan Bicek; Dusan Skrada; Jan Brezovicky
Priority date: 1986-10-06
Filing date: 1986-10-06
Publication date: 1988-04-15
Also published as: CS718986A1

Abstract

Riešenie sa týká spůsobu čistenia odpadových vůd z výroby N-fenyl-N‘-izopropyl-p- -fenyléndiamínu. Na odpadové vody s obsahom do 1,0 % hmot metanolu, připadne zriedené vodou až do objemového poměru 1 : 1, sa působí aromatickým uhlovodlkom so 6 až 8 atómami uhlíka, s výhodou toluénom, množstve 0,5 až 10,0 % hmot., vzhfadom na neriedené odpadové vody, pri teplote 35 až 110 °C a pri strednej době zdržania 0,5 až 60 minút. Riešenie je možné využit v chemickom priemysle.The solution relates to a method for treating wastewater from the production of N-phenyl-N'-isopropyl-p-phenylenediamine. Wastewater containing up to 1.0% by weight of methanol, or diluted with water up to a volume ratio of 1:1, is treated with an aromatic hydrocarbon with 6 to 8 carbon atoms, preferably toluene, in an amount of 0.5 to 10.0% by weight, based on undiluted wastewater, at a temperature of 35 to 110 °C and an average residence time of 0.5 to 60 minutes. The solution can be used in the chemical industry.

Description

Vynález sa týká sposobu čistenia odpadových vod z výroby N-fenyl-N‘-izopropyl-p-fenyléndiamínu.The present invention relates to a process for the purification of waste water from the production of N-phenyl-N‘-isopropyl-p-phenylenediamine.

Pri výrobě antiozonantu N-fenyl-N‘-izopropyl-p-fenyléndiamínu sa používá ako' medziprodukt 4-amínodifenyl-amín, připravený katalytickou redukciou vodno-metanolického roztoku sodnej soli 4-nitrózodifenylamínu vodíkom za přítomnosti organického rozpúšfadla a s použitím kovových hydrogenačných katalyzátorov (ČS AO 184 062). Vzniknutá emulzia vodnej a organickej fázy sa v separátore rozdělí a vodná fáza s obsahom 15 až 20 % metanolu sa vedie do kolony na regeneráciu metanolu. Organická fáza s obsahom 4-amínodifenylamínu sa vedie na rektifikačné kolony, kde sa v troch stupňoch izoluje čistý 4-amínodifenylamín, ktorý sa používá v ďalšom syntéznom stupni. Vařákový zvyšok v metanolovej koloně tvoria farebné odpadové vody s obsahom metanolu do 1,0 %. Sfarbenie je spósobené obsahom 4-amínodifenylamínu, nitro- a nitrózoderivátmi difenylamínu [do 0,5 % hmot.). Odpadové vody ďalej obsahujú 2 až 10 % hmot. NaOH a 5 až 10 % NaCl. Chemická spotřeba kyslíka (CHSK) pri týchto odpadových vodách je 30 000 až 60 000 mg O2/I.In the preparation of the N-phenyl-N'-isopropyl-p-phenylenediamine antiozonant, 4-aminodiphenylamine is prepared as an intermediate prepared by catalytic reduction of an aqueous methanolic solution of 4-nitrosodiphenylamine sodium with hydrogen in the presence of an organic solvent and using metal hydrogenation catalysts. AO 184 062). The resulting aqueous and organic phase emulsions are separated in a separator and the aqueous phase containing 15-20% methanol is fed to a methanol recovery column. The organic phase containing 4-aminodiphenylamine is fed to rectification columns, where pure 4-aminodiphenylamine is isolated in three steps, which is used in the next synthesis step. The residue in the methanol column consists of colored waste water with a methanol content of up to 1.0%. The coloring is due to the content of 4-aminodiphenylamine, nitro- and nitroso derivatives of diphenylamine [up to 0.5% by weight]. The waste water further comprises 2 to 10 wt. NaOH and 5 to 10% NaCl. The chemical oxygen demand (COD) for these waste waters is 30,000 to 60,000 mg O2 / L.

Odpadové vody s teplotou 105 až 115 °C sa cez utilizátor tepla, kde sa ochladla na teplotu 40 až 60 °C, vedu na chemická úpravu, ktorá spočívá v neutralizácii minerélnou kyselinou a v separácii chemického kalu, vylúčeného pri neutralizácii.The waste water at 105-115 ° C is passed through a heat utilizer, where it has been cooled to 40-60 ° C, to undergo a chemical treatment consisting of neutralization with mineral acid and separation of the chemical sludge that is eliminated during neutralization.

Manipulácia s odpadovými vodami a ich transport na chemická úpravu sú v podstatnej miere negativno ovplyvňované vylučováním časti organických látok, tvoriacich postupné smolovité usadeniny na stěnách zásobníkov, potrubia a armatúr a to až do takej miery, že dochádza k ich zaneseniu, čo si vyžaduje odstavenie technologického procesu. Takto zanesené technologické zariadenie sa musí čistil manuálně, pričom dochádza k styku s nebezpečnými a zdraviu škodlivými látkami.Wastewater handling and transport for chemical treatment is substantially negatively influenced by the elimination of a part of organic substances forming gradual pitch deposits on the walls of tanks, pipelines and fittings to the extent that they become clogged, which requires the shutdown of the technological process. process. The process equipment so clogged must be cleaned manually, in contact with hazardous and harmful substances.

Likvidácia polotuhých organických látok je problematická, pretože deponácia na skládku tuhého odpadu nie je možná vzhladom na ich toxické vlastnosti. Spalovanie si vyžaduje zasa speciálně zariadenie. Vysoká CHSK odpadových vód si vyžaduje poměrně nákladná chemickú úpravu před odvodom na biologické čistenie. Je preto žiadúce v odpadových vodách znížif obsah organických látok a následné CHSK už před ich vstupom na chemickú úpravu.The disposal of semi-solid organic substances is problematic, since deposition in a solid waste dump is not possible due to their toxic properties. Incineration requires a special device. The high COD of waste water requires a relatively expensive chemical treatment prior to removal for biological treatment. It is therefore desirable to reduce the content of organic substances in wastewater and the subsequent COD before they enter the chemical treatment.

V praxi sa zistilo, že biologické čistenie týchto odpadových vód s obsahom 4-amínodifenylamínu je skomplikované tvorbou pěny v aerátoroch, čo znižuje účinnosl procesu biologického čistenia a vyžaduje si následná aplikáciu odpeňovacích prostriedkov.In practice, it has been found that the biological purification of these 4-aminodiphenylamine-containing waste waters is complicated by the formation of foam in the aerators, which reduces the efficiency of the biological purification process and requires subsequent application of antifoams.

Z obsahu 4-amínodifenylamínu v odpadových vodách (0,05 až 0,2 % hmot.) vyplývá, že doteraz sa takto stráca bez užitku 0,5 až 1,0 % hmot. z celkového množstva 4-amínodifenylamínu v technologickom procese výroby N-fenyl-N‘-izopropyl-p-fenyléndiamínu a jeho recykláž do procesu je vzhladom na vysoká cenu, žiadúca aj z ekonomického hladiska.The content of 4-aminodiphenylamine in the waste water (0.05 to 0.2% by weight) shows that up to now, 0.5 to 1.0% by weight has been lost. of the total amount of 4-aminodiphenylamine in the technological process of producing N-phenyl-N‘-isopropyl-p-phenylenediamine and its recycling to the process is due to the high cost, also desirable from an economic point of view.

Uvedené nedostatky odstraňuje spósob čistenia týchto odpadových vód podlá vynálezu, ktorého podstata spočívá v tom, že na odpadové vody s obsahom metanolu do 1,0 % hmot., připadne zriedené vodou až do objemového poměru 1 : 1 sa pósobí aromatickým uhlovodíkom, s výhodou toluenem, benzénom, xylénom alebo ich zmesou v množstve 0,5 až 10 % hmot. vzhladom na neriedené odpadové vody, pri teplote 35 až 110 °C a pri strednej době zdržania 0,5 až 60 minút.The above-mentioned drawbacks are eliminated by the method of purification of these waste waters according to the invention, which consists in the treatment of waste waters with a methanol content of up to 1.0% by weight, optionally diluted with water up to a volume ratio of 1: 1. %, benzene, xylene or a mixture thereof in an amount of 0.5 to 10 wt. with respect to undiluted waste water at a temperature of 35 to 110 ° C and a mean residence time of 0.5 to 60 minutes.

Čistěním odpadových vód podlá vynálezu sa z odpadových vód 4-amínodifenylamín odstráni takmer úplné. Odstránia sa i časť vysokomolekulárnych látok, ktoré spolu s 4-amínodifenylamínom spósobujú vysokú CHSK odpadových vód a penenie v aerátoroch pri ich čistění na biologickej čistiarni, resp. po ochladení sa postupné vylučujú, s čím sú spojené už spomenuté problémy.Purification of the waste waters of the invention removes almost 4-aminodiphenylamine from the waste waters. Some of the high molecular weight substances that together with 4-aminodiphenylamine cause high COD of waste water and foaming in aerators during their purification at the biological treatment plant, respectively, are removed. after cooling, they are gradually eliminated, with which the aforementioned problems are associated.

Čistenie odpadových vód podlá vynálezu je možné robit bud rozmiešaním obidvoch fáz a ich následnou separáciou, alebo v zariadení s účinnosťou niekolkých teoretických stupňoch. Potřebná úroveň čistenia závisí od obsahu znečisťujúcich látok a je možné ju meniť aj množstvom použitého rozpúšťadla.The wastewater treatment according to the invention can be carried out either by mixing the two phases and then separating them, or in a plant with efficiency of several theoretical stages. The level of cleaning required depends on the pollutant content and can also be varied by the amount of solvent used.

Aromatické uhlovodíky sú na čistnie odpadových vód podlá vynálezu optimálně, v odpadových vodách s obsahom soli do 20 % sú prakticky nerozpustné, majú pro separáciu 4-amínodifenylamínu a jiných derivátov difenylamínov vysoký rozdělovači koeficient a sú poměrně lačné. Najvýhodnejšie sú toluén, benzen, xylen a ich zmesi.Aromatic hydrocarbons are optimal for wastewater treatment according to the invention, are practically insoluble in wastewater with a salt content of up to 20%, have a high partition coefficient for separation of 4-aminodiphenylamine and other diphenylamine derivatives and are relatively fasting. Most preferred are toluene, benzene, xylene and mixtures thereof.

Výhodou nášho postupu je, že sa prakticky kvantitativné odstráni vylučovanie organických látok, ktoré majú sklon tvořit smolovité usadeniny z odpadových vód po oddestilovaní metanolu a po ich ochladení. Odstráni sa tak zanášanie potrubných trás a aparátov a s tým spojené odstávky technologického procesu a s negativným dopadem na produkciu a ekonomiku procesu. Odpadá nutnost častého čistenia technologického zariadenia spojená s manipuláciou so smolovitými polotuhými zdraviu škodlivými látkami.The advantage of our process is that the excretion of organic substances, which tend to form pitch deposits from waste water after the methanol has been distilled off and cooled, is virtually quantitatively removed. This will eliminate fouling of pipelines and apparatuses and the associated downtime of the technological process and the negative impact on the production and economy of the process. There is no need for frequent cleaning of the technological equipment associated with the handling of pitch semi-solid substances harmful to health.

Tieto látky (prevažne sa jedná o- 4-amínodifenylamín) sa postupom podlá vynálezu izolujú z odpadových vód vo formě roztoku v organickom rozpúšťadle, ktorý sa recykluje do technologického procesu, kde sa spracuje v příslušném zariadení a takto sa 0,5 až 1 % 4-amínodifenylamínu (z celkového množstva 4-amínodifenylamínu vyrobeného katalytickou redukciou v predchá25B dazjúcom stupni) vracia znova do výroby N-fenyl-N‘-izopropyl-p-fenyléndiamínu. Prítomnosť sprievodných látok v recyklovanom roztoku nie je na závadu, pretože 4 -amínodifenylamín sa v technologickom procese čistí trojstupňovou rektifikáciou a látky sprevádzajúce recyklovaný 4-amínodifenylamín sa podlá svojho charakteru rozdelia medzi predné rektifikačné frakcie a vařákové zvyšky.These substances (predominantly 4-aminodiphenylamine) are isolated by the process according to the invention from waste water in the form of a solution in an organic solvent, which is recycled to the technological process, where it is treated in the respective plant and thus 0.5 to 1%. -amino-diphenylamine (from the total amount of 4-amino-diphenylamine produced by catalytic reduction in the previous 25B stage) returns to the production of N-phenyl-N'-isopropyl-p-phenylenediamine. The presence of the accompanying substances in the recycled solution is not a problem, since the 4-aminodiphenylamine is purified in the process by a three-stage rectification process and the substances accompanying the recycled 4-aminodiphenylamine, according to their nature, are divided between the front rectification fractions and reboiler residues.

Ďalšou výhodou je zníženie CHSK odpadových vod, čo je z hladiska ich spracovania na biologickej čistiarni velmi žiadúce ako aj odstránenie niektorých látok (predovšetkým 4-amínodifenylamínu), ktoré ako prax ukázala sposobujú penenie odpadových vod v aerátoroch pri ich čistění na biologickej čistiarni odpadových vod.Another advantage is the reduction of COD wastewater, which is highly desirable from the point of view of treatment at a biological wastewater treatment plant, as well as the removal of some substances (especially 4-aminodiphenylamine) which have shown to cause foaming of wastewater in aerators.

Vynález je bližšie objasněný na konkrét nych príkladoch.The invention is illustrated by the following examples.

Příklad 1Example 1

500 ml odpadových vůd (CHSK,.,- 35 400 miligramov na liter) s obsahom metanolu 0,1 °/o hmot. s teplotou 110 °C bolo nahatých do banky a po ich ochladení na laboratórnu teplotu (počas 12 h) bolo zistené, že na dne a stranách banky sa vytvořili smolovité usadeniny rozpustné v zmesi toluén a hydroxid sodný (v pomere 1:1). Množstvo usadenín bolo cca 0,5 g/1 odpa dových vůd. CHSK_cr odpadovéj vody bola stále vysoká — 34 600 mg/1. Odpadová vo da bola zneutralizovaná 31 % kyselinou chlorovodíkovou na pH — 6,5 a bol oddělený vylúčený kal v množstve 1,4 g/1.500 ml waste lines (COD, - 35 400 milligrams per liter) with a methanol content of 0.1% by weight. at 110 ° C was poured into a flask and after cooling to room temperature (over 12 h), it was found that pitch and pellets soluble in toluene / sodium hydroxide (1: 1 ratio) formed on the bottom and sides of the flask. The amount of sediment was about 0.5 g / l of waste leads. COD _cr waste water was still high - 34 600 mg / 1st The waste water was neutralized with 31% hydrochloric acid to pH = 6.5 and the separated sludge was collected at 1.4 g / l.

Tieto odpadové vody boli nastrekované do modelu aerátora čistiarne odpadových vůd a pri různých úrovniach aerácie boio zistené, že dochádza k ich silnému peneniu.These waste waters were injected into the aerator model of the wastewater treatment plant, and at various levels of boio aeration it was found that their foaming was severe.

Příklad 2Example 2

K 1000 ml odpadových vod (CHSK,,,. ~= 35 420 mg/1) s obsahom metanolu 0,1 ^c;b hmot. s teplotou 110 °C sa přidalo 40 ml to luénu a emulzia sa v banke intenzívně pre81To 1000 ml of waste water (COD, = 35 420 mg / l) with a methanol content of 0.1 ^c ; at 110 [deg.] C. 40 ml of toluene were added and the emulsion was vigorously pre81 in the flask

m.iešala počas 50 minút. V oddelenej toluénovej fáze bola stanovené sušina (4,55 % hmot.). V sušině bolo stanovené 95 % 4-amínodifenylamínu, zvyšok bol tvořený derivátmi difenylaminů. Filtráciou odpadovej vody cez fritu S 4 po 48 h státia pri jej posíupnom ochladnutí na laboratórnu teplotu neboli zistené vylúčené nerozpustné látky. Ani pri dlhšom státí počas 100 h nedochádzalo k vylučovaniu nerozpustných látok. Chemická spotřeba kyslíka odpadovej vody po extrakcii toluénom bola CHSK_cr = --= 26 620 mg/1.m. stirred for 50 minutes. In the separate toluene phase, the dry weight (4.55% by weight) was determined. In the dry matter, 95% of 4-aminodiphenylamine was determined, the remainder being diphenylamine derivatives. Filtration of the waste water through the frit S 4 for 48 hours at its gradual cooling to room temperature did not reveal any insoluble matter. Even after prolonged standing for 100 h, no precipitation of insoluble matter occurred. The chemical oxygen demand of the waste water after toluene extraction was COD _cr = - = 26 620 mg / l.

Příklad 3Example 3

Odpadové vody s chemickou spotřebou kyslíka CHSK., = 34 800 mg/1 s obsahom metanolu 0,1 % hmot. s teplotou 110 °C sa kontinuitne nastrekovalo do miešacej banky, kde sa přidávala voda v množstve 10 % hmot. na uvedené odpadové vody. Ďalej sa do banky privádzal toluén v množstve 2 % hmot. na uvedené odpadové vody. Zdržná doba emulzií v banke bola 2 minútv. V deliacom lieviku bola oddělená toluenová fáza, ktorá mala sušinu 9,6 % hmot. Analýzou sušiny bolo zistené, že je tvořená 95 % 4-amínodifenylamínu, zvyšok tvoria deriváty difenylaminů. Filtráciou odpadovej vody cez fritu S 4 po 48 h státia a po jej súčasnom ochladnutí na laboratórnu teplotu bolo zistené, že vylúčených nerozpustných látok bolo menej ako 0,1 mg/1. CHSK_cr odpadovej vody po extrakcii toluénom bola 26 140 mg/i vzhladom na neriedené odpadové vody. Takto upravené odpadové vody boli zneutralizované 31 °/o kyselinou chlorovodíkovou na pH = 6,5 a bol oddělený vylúčený chemický kal v množstve 1,5 g/1. Tieto odpadové vody malí chemickú spotřebu kyslíka CHSK_cr = 20 820 mg/1 a boli nastrekované do laboratórneho modelu aerátora čistiarne odpadových vod. Pri různých úrovniach aerácie bolo zistené, že pri spracovaní takto upravených odpadových vůd penenie bolo výrazné potlačené v porovnaní s príkladom 2.Waste water with chemical oxygen demand COD = 34,800 mg / l with a methanol content of 0.1% by weight. with a temperature of 110 ° C, was continuously fed into a mixing flask where water was added in an amount of 10% by weight. to said waste water. Further, toluene was added to the flask in an amount of 2% by weight. to said waste water. The residence time of the emulsions in the flask was 2 minutes. The toluene phase was separated in a separatory funnel and had a solids content of 9.6 wt. Dry matter analysis showed that it was 95% 4-aminodiphenylamine, the remainder being diphenylamine derivatives. Filtration of the waste water through a frit S 4 for 48 hours and after cooling to room temperature showed that the precipitated insoluble matter was less than 0.1 mg / l. COD _cr waste water after extraction with toluene was 26 140 mg / l with respect to the raw sewage. The treated waste water was neutralized with 31% hydrochloric acid to pH = 6.5 and the separated chemical sludge was collected at 1.5 g / l. These waste waters have a chemical oxygen demand COD of _Cr = 20,820 mg / l and have been injected into the laboratory model of the aerator of the wastewater treatment plant. At different levels of aeration, it was found that the treatment of the treated waste condensation was significantly suppressed compared to Example 2.

Claims

25B 5 returns to the production of N-phenyl-Nopropyl-isopropyl-p-phenylenediamine. The presence of accompanying substances in the recycled solution is not a problem, since 4-aminodiphenylamine is purified by a three-step rectification process and 4-aminodiphenylamine-recycled materials are divided between the front rectification fractions. and sausage residues. A further advantage is the reduction of COD waste water, which is very desirable from the point of view of their treatment at a biological treatment plant, also the removal of some substances (especially 4-aminodiphenylamine), which have proven to cause foaming of wastewater in aerators. when cleaning them with a biological wastewater treatment plant. The invention is illustrated by the following examples. EXAMPLE 1 500 ml of waste lines (COD, .about.400 .mu.g / liter) with a methanol content of 0.1% by weight. 110 ° C was charged to the flask and, after cooling to room temperature (for 12 h), it was found that the bottom and the bottom of the flask formed a solute-soluble toluene-sodium hydroxide (1: 1). : 1) .The amount of deposits was about 0.5 g / l wastewater. CODcr waste water bolast high - 34 600 mg / 1. The waste water was neutralized with 31% hydrochloric acid to pH = 6.5 and the precipitated sludge was separated at 1.4 g / l. These effluents are injected into the aerator of the sewage treatment plant and are found to be heavily foamed at various levels of aeration. Example

2 to 1000 ml of wastewater (COD, ~ 35 = mg 420 / l) with a methanol content of 0.1 c; at 110 ° C, 40 ml of t-toluene was added and the emulsion was vigorously stirred in the flask for 50 minutes. The separated toluene phase was dried (4.55 wt%). 95% of 4-α-aminodiphenylamine was determined in the dry state, the remainder being dilenylamine derivatives. Excreted insoluble matter was not detected by filtration of the effluent through the S 4 frit after standing for 48 h at its gradual cooling to room temperature. Even with prolonged standing for 100 h, insoluble fluxes did not precipitate out. The chemical oxygen demand of the effluent after extraction with toluene was CODcr = 26,620 mg / L. Example

3 Waste water with chemical consumption COD COD = 34,800 mg / l with a content of 0.1% by weight of methanol. at 110 ° C, it was continuously sacrificed into a mixing flask where 10% w / w water was added. to the waste water. In addition, the set flask supplied toluene at 2% by weight. to the waste water. The emulsion flask in the flask was 2 minutes. The toluene phase was separated in the separating funnel and had a dry weight of 9.6% by weight. The dry analysis was found to be 95% of 4-aminodiphenylamine, the residue being derivatives of diphenylamine. Filtration of the waste water of frit S4 after 48 hours of standing and cooling it to room temperature at the same time revealed that the insoluble matter was less than 0.1 mg / l. CODcr evaporation water after toluene extraction was 26 140 mg / l relative to undiluted water. The treated effluents were neutralized with 31% hydrochloric acid to pH = 6.5 and the separated chemical sludge was separated at 1.5 g / l. These waste waters had a chemical oxygen demand of CODcr = 20,820 mg / l and were sprayed into a laboratory model of a wastewater treatment plant aerator. At various levels of aeration, it has been found that in the treatment of such effluent condensation, it has been markedly suppressed by comparison with Example 2. The process of purifying wastewater from the N-phenyl-N'-isopropyl-p- phenylenediamine, characterized in that an aromatic hydrocarbyl of 6 to 8 carbon atoms, with advantage of toluene, is treated with waste water containing methanol up to 1.0% by weight, optionally diluted with water up to 1: 1 by volume. 0.5 to 10.0% by weight, based on undiluted waste water, at a temperature of 35 to 110 ° C and at a mean residence time of 0.5 to 60 minutes.