DE1417641A1 - Continuous sorption process - Google Patents

Description

@continuiarliches @orstionsverfahren @ riorität: from May 20th 1 @ 59 in U.3.A. under the Hummar 314 587 @ie invention concerns in procedures sur separation of components contained in a mixture of compounds in which brings this mixture into contact with a stationary mass of solid @ sorbent, that a selective sorption capacity for one or more components of the mixture and significantly lower absorption capacity for at least one other ingredient who has @ ugleitten Mischu @ g. In particular, the invention is concerned with an improvement in a separation process of the type mentioned above, in which the raw mixture dur @ n a part of the solid @orbent is passed which contains one or more of its constituents Raw mixture @orbs while Oi @ enorbens @ @@@ at the same time @ g by another Part of the feston @orbensmesse goes and from it bestaniteile desorbiort, which at a previous contact with the raw mixture have been sorbed. Through guidance from Spelse- u @ d @ eserbe @@ tr @@@@ in different periods or zones of solid sorbent, @ie i @ are arranged in a single @ett or in @ multiple beds in @ rows, @relation of raffin @ t and sorbate product outlet streams from other zones in the msb series @Connection of the inlet and outlet flows Ln these zones, and from these according to A previously determined cycle becomes a counterflow from Rehbesehi @ kung and faked solid @orbans. The present improvement covers the use an Aumspülstro @@@, whereby the purity is shown as products from the process deducted Streams will be greatly improved.

The present invention is an improvement on a recently developed one continuous sorption process, which is described in the German patent application U 6379 IV @ / 12d is described and at d Cin continuous cyclic circle run Von Superplasticizers, which can be in the liquid or steamed state, aufwin @ nderfahren @ by means of four in-line building up a place. solid mass of solid Sorbent and from the outlet of the last zone back to the inlet of the first zone is, the raw mopping finished in the circular flow fluid a @ the inlet of the first Zone introduced, no sorbed constituent is continuously removed from the circulating solvent a @ Out @ leave the first zone withdrawn, @ eeorben @ continuously in the surrounding area Solvent introduced into the third zone, selectively absorbed constituent and desorbents @ are continuously withdrawn from the outlet of the @ritt zone and the four zones periodically proceed in the ort @ fixed sorbent mask @@ by @@ n at the same time the point of introduction of the Bo @@ ischung, German Ab @ ngs @ point of the non-sorbed component the introduction of desorbent and the withdrawal of selectively serbated @estandteil and deserbee each by an equal @streeke along the flow path of the continuous circulating fluid can progress. The improvement according to the lying Invention is gekennzeischnet that a flushing flow, for the as materials Possible options are 1. a clear of the components of the raw material Superplasticizer and 2. the selectively sorbed component from the raw jungle, according to any such redirection is routed through the Darchlaufweg that is currently Bringing Rohmi @ chung into the first zone before continuing, and consequently one Preduktstrom from the process carries, and this @ pülstrom in such an amount Through this Flow path is passed that practically all raw mixture is displaced from this flow path into the continuously circulating fluid.

The present method is general to separation by absorption as well as by adsorption of flowing constituents on solids and applicable is therefore generally referred to as a sorption ancestor. It is applicable to Separation methods in which the mixture to be broken down with @ so-called molecular @ ioben comes into contact, the salektiv ate ingredients of the mixture with a special Work out the molecular structure or configuration. Adsorbents that were selectively saturated Compounds such as olefini @ ehe and aromatic hydrocarbons and organic Retain compounds with polar radicals due to surface properties of the solid adsorbent, are for example such solid adsorbents as (dehydrated) Sili @ agel, activated Helsk @ hle, the aluminum @ ilicates, vi. the ver @@ hiedenen Tene and activated Ki @@@ l @@ uregele a @ ohlisßli @ he such typi @@@ hen example, like attapulgmeton, mentuorillonite, entuä @@ erte, artificial masses made from clay and silicic acid obtained by heating to a temperature ii range of, however somewhat are activated below the approximate melting point of the mass Clay, especially clay and other similar characters. Festivals Molecular @ i @ btype sorbents, which are br @@@ hbar in lying processes, as per @@@ @ lkali- and Erd @ lkalial @@ iniumeilikatsorbentien, are among other things selche, which @ or @ m of about 4 Ångstrom units in cross-section @ durobm @@@ er (for example in the decomposition of aliphatic hydrocarbons with 2 to 4 carbon atoms each @ olekül breakable) and selenium @, the @oren of about 5 Ang @ tr @@ - units in cross section through @@@@@@ have, i.e. @oren, which are large enough, - dea entry of straight-chain connections, such as straight chain hydrocarbons of 4 to 20 carbon atoms, permitted, however, not large enough to contain connections of branched or cyclical structure to record.

Significant Rohmis who come into contact with a testing activated adsorbent are e.g. paraffinic hydrocarbon fractions, like a gasoline fraction containing @er @@@ tane and / or @mine, the latter being polar Compounds are selectively retained on the adsorbent particles, mixtures of @ ar @ ffins and olefins, in which the olefinic constituent is selected selectively by the solid adsorbent is adsorbiort, mixtures of aromatic and non-aromatic Hydrocarbons, from which the aromatic constituent is selected from the solid Adsorbent is adsorbed, mixtures of Wa @ serdam @ f and an inert gas, such as Nitrogen or air with moisture content that is adsorbed on its own, mixtures of phenols and / or the sulfur compounds, wto thiohenes are liquid hydrocarbons, the phenolic or sulfur compound being selectively adsorbed and numerous at the. Application forms that are known in chemical technit.

@A characterizing raw mixes used in the present process an @orbens of the previously mentioned type with pores of 4 to about 5 Å @ gstrom units in the @ uschnittsdurchm @@ ner @ are detachable, si @ d carbon @ hydrogen mixtures with hydrocarbons of straight-chain structure and hydrocarbons of denied or cyclic Structure. For example, a hydrocarbon with a branched @@ tte, such as 2,3-dimethylbutane or a cyclic hydrochloride lvi. Cyclcheran or a mixture of these Hydrocarbons easily as a non-sorbed raffinate from a straight chain Hydrocarbons, such as n-hexane (the initial mixture is usually quite difficult separated by fractional distillation to decompose) by adding the raw mixture This Haxane contains particles of the solid, just mentioned sorbent, such as, for example, its dehydrated Bringing metal aluminosilicate sorbent into contact, the so-called @ogen-poor molecular sieve is known.

@ i @ e other type of separation process to which the present process flow applies is applicable, consists of a chemical reaction with a solid sorbent (reaction s @ artner), you are held in place as a fixed bed, with the absorbable fixed part, the other reaction partner, the one in a flow of solvent containing the latter is approved. The removal of @rdalkali metal is indicative of a zolehe separation the so-called hard water, u @ the latter a @ urch to soften it and / or to deionize it in a @ @eionization process or a decarbonylization process for the separation of aldehydes, @etones and carboxylic acids from a non-aqueous, alcohol mixture.

The present proceedings can be redeemed immediately developed, continuous sorption processes are presented as if as in a series of four pre-bonded zones of a single mass solid sorbent carried out without an actual border line between all these zones is canceled from the fact that the zone boundaries through the inlet and outlet points for the different fluid streams are defined by si @ d. The zone in which @ r the fresh Raw mixture is introduced is referred to as the sorption sonic, the next downstream zone is the @ rimärs rectifier @ one, which in the downstream flow is the following Nao @@ te zone @ie @ esor @ tionnzone and the fourth and last zone in the flow is the secondary rectifying zone. That solid sorbent is usually in an elongated vertical column, preferably in prom a la @@ en to @@@@ enhungenden @ orbens @@ sse. @ Weis @ is also preferred to sorbent @@@@ in a row of Abtelen or Batten with a significantly reduced @cutting divided between each compartment and each reduced section also contains sorbent. The last, particularly preferred arrangement is in the @chsmatic drawing which is described in more detail below.

In the present process as well as in the one mentioned recently developed, continuous sorption process is used when operating with the solid Sorbent in a series of fixed @ettes the raw mixture at the inlet end of one of the fixed beds and flows through this first bed that is not sorb @ erte @@ part of the chmischu @ g leaves the first bed in the Sorptienszone and @ enters the next bed of the sorption zone in the descent. @ in @ sufficient number solc @ er fixed beds in @@ lhe (obgle @ ch in some cases also a bed is sufficient) are provided at @ in @@ lying and connected to oraction completely absorbs the @component (the @orbate) from the @ohmixture to remove and to obtain a stream of non-morbid or raffinate components, the one from the outlet of the last @ette of the sorption zone emerges. Of the The outlet from this last @ et @ of the sorption zone is held by an outlet opening the part of the raffinate which is not sorbed is withdrawn as a mixture with part of the continuously circulating flow of fluid. @er @ remaining Part of the outflowing refined stream from the sorption section continues to flow by one or more subsequent fixed beds, which form the primary octification zone of the procedure and is connected to the outlet from the last bed in a rectifier section by an emerging desorbent stream. The esorbent (ei @ Matorial, which is in the lag @, from the solid Sorbe @ s the @component of the raw mixture to displace, the prepared during a previous operating cycle on the solid sorbent) flows through one or more of the following @etten, which represent the desor @ ti @ nszone. The @trom that flows in this zone therefore consists of a mixture of deserbe and sorbate, which was previously made from the raw mix @@ was sorbed in a previous company journey and by the f @ ston sorbent that contact with the @osorbens has been released. The @esorbens is used in introduced in an amount that corresponds to a molar ratio of @desorbons (which the @orbens surrounds) to sorbate (within the pores of the sorbent) at any given point at least greater than 1: 1 and preferably a molar ratio of at least 10 : 1 to about 30: 1 results. At the end of the desorotion section of the process flow becomes a stream that consists of a portion of the sorbate, @esorbent and circulating fluid (if the latter is different from @em desorbent) consists of the processes as Final product or, if necessary, as an intermediate product, sucked off for further purification, This Strem can, for example, be fractionated in an auxiliary distillation unit, to separate the desorbent from the relatively pure sorbent product. The remaining one Absorbent content and sorbate that does not deform through the @esorbent sorbate outlet has been, its flow continues downward by one or more subsequent, festli @@ ends Sorbent beds, which are used here as a secondary @ectifying zone @ the process flow be - @@ i @@ t are in which the raffinate from the orbens and the spaces @ between @en sorbent particles through which @esorbent-sorbate-mishu @@ is washed out. The mixture of desorbent and circulating fluid that drains from the includes the last bed in the secondary rectification section, now @ t pre-settles with the incoming raw mixture, if the latter in the first bed of the or @ tion zone, as mentioned above, occurs.

@ during the course of the above continuous process for or @ tion and @ esor @ tion, the @ introduction points @ of the raw mixture and the @osorbent in the Circulation and the points of disposal of non-sorbed or raffinate base part of the Raw mixture as well as the sol @ ctively sorbed or sorbate component periodically at the same time u @ d to the same extent on @tellen stromab @@ rts of their previous @position switches. Finally, it reaches the point of introduction of the raw mixture in the process flow the place where sorbate component is removed in a previous stage of the process and thus a cycle in the operation @ cycle is completed.

Each bed in the system is an outboard through a line Distribution center connected that from time to time a trom in the bed or out of it, depending on the particular process, it is the bed is located, as determined by a predetermined program, under walchem the distribution center is working. At a given moment during the procedure receives a bed of the raw mixture series from the distribution center through pipes and valves, preferably the inlet of the bed (which is also the outlet of the next Represents bed flow upwards) connects to the distribution center. From the outlet A bed further downstream are the unsorbed components of the raw mixture also through connection lines, valves and other devices that lead to the distribution center lead, sucked off. There is a layer further downstream at the same time in the state of supply by similar lines and valves with one Desorbent stream, while the sorbate at a point even further downstream (@@ selectively sorbed component of the raw mixture) from the sorbent through the desorbent displaced and from the outlet of the last bed of the absorption zone through connecting lines and valves removed by the same distribution center can lead to e @@@ r external separating or pre-setting device to g @ -lang @ n.

A transfer of funds is in the system (to a suitable @telle between two adjacent beds) provided, u @ a continuous to maintain the cyclic flow of circulating sweetener. After one before The relevant inlet and outlet positions are fixed lengthways Fließmitt @ ls vorgoschobun circumnavigate the path, by opening in @bstromrichung the next adjacent @ett in the series sc @ alt @ t. This @ eriodisch @ switching takes place by opening and closing suitable valves in each of the connecting lines of beds to de @ distribution center. @e can be seen that with the previously selected, recently developed, continuous sorting process the lines and part the Anl @ g @ that last carried the raw mixture to the last previous upflow bed (namely just before the switchover takes place) n @ ch Roh @@@ chung contain and that if the line @ie connects a bad bed to the distribution center, then used to deliver sorbate ingredient to the distribution center that remaining, thus in this line and the @onstigen @nalge n @ ch available raw mixture will pollute the @orbat stream. However, if according to the present invention the management and equipment, the final ohmic from the center of advantage to the Contact with the solid sorbent carried, to be rinsed, immediately after the river on the next bed in the row (and so on the next @ t @ llung i @ @er Sorbenemas @@) is switched, with a flushing flow in an amount that this line and system freed from the mix of @ other @chmixes contained therein, if such a @line den Sorbate stream carries, after a subsequent switching of the inlets and outlets the sorbate is only mixed with the flushing stream, from which the @orbate easily flows through Fractionation or other measure is separated. In the present case So every line or every @urch @@@@ that the distribution center or the @ rogrammei @ direction connects with the sorbent mass and @rund is @ er use for guiding the raw mixture into the @ or @ tion zone of the upstream flow of the raw mixture contains, vo @ according to its content of raw mixture through the flushing flow in any event of such use and before any other stream of proceedings goes through the same line or the @ urchlaßweg is freed.

@ a rinsing or cleaning stream that can be used for this purpose, a normally frozen material such as nitrogen, carbon monoxide, Carbon dioxide, methane, ethane or @ ro @ an, or it can be the desorbent act that is used in the process (usually a material that is can be easily separated from the sorbate product) or a liquid that is essential boils above or below the boiling point or boiling range of the raw mixture.

The operation of the process using the improvement according to the present compound and a suitable apparatus sur performing a such operation are shown in the drawing (Fig. 1 and 2> er1Mut0 any suitable Apparmtur, which is a series of fixed beds or a single contiguous Sorbent bed with a solvent connection between the beds or at the distance has lying spots in the cohesive bed and a suitable device, Ite a multi-way valve or a distribution head and individual valves for the circuit the inlet and outlet points for the various raw and product streams that occurs in the ancestor can be used. One of the preferred Types of contact apparatus is illustrated in Fig. 1 by column 101, which is suitable wise shaped separating means, which the @onvertical column in a row of adjacent Contact levels or beds 201 to 212 divided. Every step or bed is from the adjoining steps or beds, apart from the top and bottom Step, through a funnel-shaped partition, e.g. a partition wall 102 in step 201 with an all-tube 103 of a narrowed cross-section, which turned into a b @ nn @ h Level 20? opens, divided by a transverse dividing member 104 which represents the upper granse of level 202.

A suitable program device for changing the inlet and Outlet points to the contact column and to the switching of each of these points by the same Stretching in the downstream direction during the operation of the process is due the circular valve 105 @ rläntert, which has a valve housing A and a continuous circumferential K @ ken B, which is rotatable in the housing A in fluid-tight relationship. @as Housing A contains inlet and outlet openings 1 to 12, which are arranged in such a way that that they are connected to at least four internal passageways that are at least open two separate @ ialassstroms and at least two separate outlet streams. The two inlet passageways alternate with the two outlet passageways.

FIG. @ Is a larger cross-section of the valve shown in FIG and explains the internal lines for promoting a klei @ e @ @@@ latromes as well as the g @ separated inlet and @ d outlet streams.

Opening 1 in valve housing A represents an opening through which Fluid flows into the valve box through line 106 or from the valve plug be carried out. The line 106 connects opening 1 1 valve housing with the @@ itze of the contact bed 201. zsr similar iron connects opening f it 'valve body the opening valve with line 107, the one with the all tube 103 between the contact beds 201 and 202 of the column 101 is connected. In such a way the openings connect 2 to 12 in the valve housing with the contact beds 202 to 212 through a connecting line, for each relevant position of the valve plug opposite one @ of the different Inlet and outlet streams flowing in processes can be opened or closed can.

For the sake of simplicity, the method according to the invention is used described with reference to a specific raw mass, eie from a mixture consists of normal, cyolo and ischeres and is related to a solid sorbent, that of separated, essentially granular particles of a metal aluminosilicate bes @@ ht, as it has been referred to above as molecular siab.

The hexane mixture is fed into the process through line 108 with a by valve 109 regulated speed in a central cal Lf of the chick B, which is divided into four compartments by a dividing part 111 is. This raw mixture is exhausted through opening 11 @ in @ urchlaß 113, which with the outlet opening 1 of the housing A is connected. The current then enters 1 line 1 @ 6 connected to line 134. These promotes circulating Carrying means from the bottom of the contact column (bed 212) to the top of the contact layer 201. Raw mixture entering us bed 201 touches the molecular sieve sorbent, that selectively loads the normal paraffin component of the raw mixture o @@, un @ the isoparaffinic and excludes cycloparaffini @ chen components from it. These are not straight chain Connections are the main constituent parts (together the bit @ written below Carrier flux) of the stream withdrawn from bed 201 through downcomer 103. Approximately in the bed 201 leaving the current remaining n-component tends to in order to remove most of the current through the sorbent in the contact bed 202. in the In general, there is a sufficient number of interconnected, fixed beds in order to remove the @ormal component of the @ohmixture and only branched and leave cyclic @ ohbesta @@ parts in the outflow UL.

The constantly circulating fluid, the above as a carrier fluid usually consists of an excess of desorbent and im The case of sorption with a molecular sieve-like sorbent is predominant from a compound with a straight-chain structure with a lower boiling point and lower molecular weight than the straight-chain compound of the raw mixture, which is to be separated. In the present explanation in particular, normal butane is used named as carrier fluid and led to bed 201 through line 134, in which it practically occupies all @ors of the sorbent before tue. Raw mix begins, flow in this bed na. However, the more raw mix continuously into bed 201 flows before the circuit of the carbon mix is completed on the zone 202, pushes forward n-Haxane n-Buton-carrier flic @ agent from the proene of the molecular sorbent.

One of the downstream contact zones, like the bed flor, is there. last bed be in the ttenroihs that make up the sorption section @er @olonne, and the outlet stream that leaves the set 203 is @raktioch a pure refined component (i.e. cyclohexane and ischexene) mixed with excess carrier superplasticizer.

After the flow of fluid has passed through contacts 3, at least a part of it is deducted through line 115, which with the opening 4 is connected in Vontil 105. @this raffinate stream that is deformed from the column The process becomes through opening 4, passage 116, hole 117 and raffinate outlet line 113 promoted. The amount of spill removed in this way is regulated by valve 119 to a residue of raffinate mixture in column 1 @ 1, the i @ the underlying Contact bed 204 flows.

@ie sor raffinate residue appropriately carries at least 20% by volume of the flowing material in downcomer 114 and preferably at least 40 up to about 30 @ of these. @if this residual flow continues through bed 204 and the ones below Beds, the carrier superplasticizer n-butane wets the inner pores of the solid sorbent the isohexane and cyclohexane raffinate components will occupy the spaces or spaces between the particles of solid sorbent.

The row of beds between the point of the raffinate discharge through the line 115 and the port of the desorban inlet described below the primary rectifying section, in which the constituents of the fluid flow rearrange yourself.

The branched-chain and cyclic @exane components tend towards this section, which are present in the remainder of the flow of solvent, which is the raffinate discharge line 115 goes, to concentrate in bed 2 @ 4 well, much less will be in bed 205 and practically none if present in bed 206 all the time. Consequently raffinate does not contaminate the circulating fluid stream beyond the third or at least the fourth bed downstream of the bed from which raffinate is withdrawn will.

At one of the series of sorbent beds a little further downstream A desorbent stream is directed into the contact column, e.g. at the downpipe 120 101 sent in, whereby it sicli with the medium flow leaving the bed 206 iced up.

Desorbes, which also act as a carrier superplasticizer, such as vorer @@ hnt, acts, is added to the process flow through line 122 in amounts determined by Valve 123 to be regulated, sent in. The current then flows into the inner Passage 125, through hole 124 in the hollow shaft of plug B of valve 105 Inlet opening 7 in the housing A of the valve 105 and then into the line 121, the leads to downpipe 120. The amount of desorbent thus admitted into the process is sufficient to get out of the @ors of @olokularsiobzorbens dsn vorhor from the Raw mixture In a preceding part of the operating cycle, the n-hexane component is sorbed to displace.

The n-Dutanmengs required to produce this result is, is in general about 1.5 with about 15 moles of desorbents per mole of normal or straight-chain component, @er sorbed from the bohemian mixture in the @oren of the sorbent has been, preferably in the present example about to about 10 Hol n-butene per mole of sorbed n-hexane. In the case of other raw mixtures and for other separation systems must the molar ratio of desorbents only to the predominant compound also in the above order of magnitude liegon.

@is mixture of @esorbens (n-eutane) and displaced sorbate (n-hexane), as a result of the dilution of n-hexane from the consumed orbens by the n-butane is formed, flows from bed 207 into contact beds 203 and 209 and finally into the downcomer 126 with the outlet line 127 attached to it is. The outlet formed by line 127 is the first open outlet from which the mixture containing n-Batandeserbe and freige @@ tstes n-Hoxansorbat from the row of beds can be connected and the raffinate outlet line 115 can be withdrawn, because all other escape openings through the valve are through the fixed part of valve plug E blocked. The fluid stream exiting bed 209 flows through outlet opening 10 of valve 10 @, passage 129, Lech 129 and through line 130 and valve 131 hernus in an additional treatment system, which is not shown is to be further cleaned or, if desired, to the accumulating Mixture to use. Such an additional system can consist of distillation devices e.g. for the separation of an enriched n-butane stream (dsr 6m can be conducted consist of a separate fraction of n-hexanesorbate.

In order to have a residual flow for continuous operation in the process plant to create, is only a portion of the total flow at the outlet of the contact zone 203 arrives, withdrawn from the downpipe 126 for the purpose of Ausreges from the process. The remainder of the mixed stream of n-butane and n-hexane stops flowing into the contact bed 210 and the following beds of solid sorbent away, which causes a further rectification of the mixed components. The series of Beds 210, 211, and 212 represent the se @ and @ r @@ re @ tifying portion of the process represents what the isohexanes from the chains by the flow of mixed n-hexane u @ d n-Buton are washed out.

A @ somewhere in the system must correspond to the circulating @ allowance ei @@ incremental increase in pressure to keep it in circulation. This is usually achieved with a @ om @ ressers or @ um @ e 133, @ie Suction is applied to the outlet from the downpipe 132 and puts it in line to a higher pressure 134 bri @ gt, which contains the valve 135, which ends the flow of the constant a @ lan @ @ Let media flow to the top of the contact zone 2 @ 1 controls to keep its @ n @ rice flow in repeat the manner described above.

Each of the operational measures described in the foregoing essentially occurs at the same time when chick B, the valve 105 continuously in the opposite direction rotates clockwise so that for a given @omment each bed afterwards progr @@@ iv becomes an upstream bed in relation to the fluid flow that flows continuously downwards in relation to this.

If the method is operated as just described, will be contaminates the sorbate and raffinate streams to the extent that that of the remainder Flux stream results, which remains in the lines from the contact column leads to the valve opening of a previous part of the operating circuit. The reason for the improvement according to the present invention is that the lines un @ facilities of the last previous @ r @ raw mixture with a @material rinsed, which is easily separable from the other desired constituent part, wherein ms @ e.g. a small sliding or equalizing flow of @@ sorbent as a cleaning fluid or a material called external s @@ lung is used when the cleaning flux is delivered by a source outside the process flow.

Figs. 1 and 2 both illustrate the embodiment of the invention which is a small desorbent side stream within the Systems through the pipes and other equipment is derived from the raw mixes just before carried, while in the alternative embodiment, the flushing of the lines and other plant electricity is introduced from an outside source. Fig. 1 and zt indicate the position of the throttle valve plug if @ohbeschickung in contact column 101 is introduced through line 106 and into which itt 201 enters. The administration, which just before brought raw loading (as the position of the rotary plug one step was before the introduction of raw storage in bed 201) was line 136, which was the Bred raw load to bed 212. @ie the means provided, making a small one Sliding flow of internally derived desorbent-rich superplasticizers from a downflow bed is branched off through @ie parts of the valve and the lines leading from the Vontil lead to the contact column, consists of a channel through plug B of valve 105, the opening 3 connects to opening 12. This channel means an independent line by the chick, creating the desorbent @trom (essentially roines @ormalbutane at @er @ explanation) from the downpipe from bed 207 through line 137 and into the Opening @ of the valve 105 can be withdrawn. The one against opening @ in line 137 flowing desorbent stream displaces the rest of the sorbet component, the Missed with desorbent, in line 137 and @opening @ as a result of the previous one Using line 137 to remove sorbate component mixed with the Desorbent, is present (i.e. when valve plug 105 was in position. in which crude mixture in opening 110, line 149 and bed 211 of the contact column entered). The desorbent flow and the sorbate desorbent mixture produced by this desorbent flow is displaced, flows through channel 133, hole 130, line 140, controlled by valve 141 and through line U2 a @ ump @ 143, which puts the pressure on @@ n electricity to a @ivemu increases as it is required to @ rub a positive pressure against the booster beds to give the contact column. The current is from Pum @@ 143 through line 144, Lech 145, @anal 146 and through opening 12 and line 136, which connects with the bed 212 ler Kontaktkolo @ connected, discharged. (Opening 12 and line 136 represent the last preceding one Raw mixture feed from de @ moment @@@, as the infeed point for Raw mix was switched to opening 1 and line 106).

@ The volume of the flushing flow used is sufficient to carry the entire raw mixture to displace from opening 12 and line 136 @ what is necessary for this purpose Volume is at least as much as the combined volume of liquid in the opening 12 and line 136. Because of the tendency towards a partial intermingling of the S @ ülstrom and the remaining rzm-displacing @ohmixture, especially at the Front between the sorbate end part cd of the @ohmixture mixed with desorbent it is generally advisable to use a flush volume that is slightly larger is as the combined @ volume of the pipe and the opening, from the @ohmixture is to be displaced, generally about 1.2 to 3.5 volumes of detergent per volume the duct and the opening that contained the remaining mixture. Sorbate ingredient mixed with @esorbens, the remainder is left behind in the flushed opening and pipe. This is not @ disruptive because the next use of the flushing line and @opening to @ Withdrawal of sorbate-desorbent mixture from the column will serve. s itt also not @ Harmful that some sorbate component mixed watt desorbent in the line and Opening can be left behind. from which the desorbent-rich stream is drawn to initiate the flushing process because this opening and lines (opening @ and line 137 in this example) in the next stage of the operating cycle can be used to convey desorbent to bed 208 and remain filled with De @ orbens until they are mixed with desorbents in a to remove raffinate component can be used at a later stage of the operational cycle. Accordingly, the preferred mode of operation of the method according to the invention, the volume of desorbent-rich Purge stream drawn down from the outlet of the bed stream into which Fresh desorbents are inserted, especially inadequately, to remove the mixture from the valve opening and the connection line of the latter with the contact column with sorbate-D @ sorbent mixture to displace that in the detergent inlet line and the opening preceding the present desorbent-rich flushing stream.

D @ füken B of the Vontile 105 slowly turned towards the Clockwise the flow of raw charge in opening 1 (and then in @ett 201) reduced because opening 1 is gradually blocked, but at the same time opening 2 and opening gradually increases the size of the opening until the whole The excess of raw mixture flows into opening 2 and no longer flows into opening 1.

@adur h becomes the @ inlet point of the raw mixture in the @ ont @ kt column vo @ line 1 @ 6, @ie feeds into bed 2 @ 1, on opening 2 and @ d line 107, the is varbunden with downpipe 103, switched.

@as @allrohr 1 @ 3 feeds the upstream line in bed 2 @ 2 1 @ 6 and the opening 1 @ 1 of the valve 1 @ 5, filled with a smudge. Simultaneously with the circuit in the line, through which raw mixture into the contact column from line 106 enters line 107, raffinate component is from the discharge stream, who leaves @ett 204, withdrawn, instead of leaving bed 2 @ 3, through the @@ before, through filler pipe 147 instead of downpipe 114 and through line 148, which carries the affinate through Opening 5 in channel 116 in the valve plug through the raffinate outlet from the colon convicted. Similarly, desorbent is displaced in bed 207 by downcomer 120, introduced into bed 203 through line 137 from port @ of the valve housing and sorbate component withdrawn from bed 210 through line 149 to port 11, the leads to Sorbatan @ laßleitung 130. @enn the circuit of the separated inlets for the raw mix and the sorbent and the separate outlets for the raffinate and the sorbate occurs, also switch channels 138 and 146 and the desorbent @ rich at the same time @flow from bed 20 @ flows through line 150 in opening @ of valve body @ Line 138 and 146 in opening 1 and then through line 106 into bed 201, the before taking up the raw mixture in the last operating stage.

@ same the use of the internally branched off from the contact column Desorbent-rich stream is generally the preferred @ uell @ of the S @@ llstromes for Removal of @ohmixture from the valve openings and connection @ lines of the Valve with the contact colone, the flushing flow can also come from an external @uelle be delivered and be different @ us @ mmensosition. @as Naßerliote @ cleaning fluid Preferably there is also @@@ @@@@@ material that can be viewed in the process vorli @ @@@@@ @@@ t @@ lteil @@ @@ separates @@@ can (@ .B. on the basis the boiling point of the cleaning liquid concerned and the sorbate and raffinate components the raw mixture) and it is even more useful to use a light gas or a liquid from low boiling point outside of the boiling point of the raw material to be used or @es i @@ process used desorbents @. In the case of delivery of one of these external faces At source, valve 141 in line 150 is closed and valve 151 in line 152 opened in verb @@ du @ g with @eitung 14 @. This lets the cleaning fluid off its external source in line 144 and @anal 146 ei @, the @@ the contact column through the valve. @ esign @ te gaseous material ion for use as a cleaning stream are inert gases such as nitrogen, carbon monoxide, carbon dioxide, methane, ethane, @ ro @ en and the like, which include the process @ through the various outlet lines escape that the contact column with the valve verb @@ lon. @as Rei @@ gu @@ s flux can also consist of pure sorbent, which is fed to an external manure which occurs in the process flow and with the various solvent flows is mixed in the column and finally through the raffinate and sorb @ tbestan @ partial outlets Will get removed.

To recover the desorbent and purification stream from the To simplify the flow of products, it is wise that those be used as deserbens and cleaning agents selected materials have a boiling point that is sufficient from the @ affi @ at- u @@ sorbate components to be easily distinguished by suitable Fractionating means, especially by simple D @@ - tillation, to be separable. separation of the cleaning agent un @ @esorbene by distillation is most effective when a material that is at least 10 °, preferably 10-50 ° below the @ nfangssi @ de @ point the raw charge is boiling and is used as a purifying and desorbent stream.

The contact procedure after the rfindung @ is preferably under Tem @@ ratur-, @ jerk and flow ratio @ e @ operated by the respective @ e @ urgent raw mixture the @orbens used in the @ ontaktzone @ under the required product unit depend. In most cases, the contact beds are used because of the fixed bed cover to the different fluid flow rates, that flow through the @nlage, Liquid phase operation is preferred, which may require the process to work Considerable pressure head arboitet to the flows in the liquid phase at the respective Maintain operating temperatures. For operation in the gas phase, the half of the @ on @ aktzone aufr @ cht @ rhaltene @ em @ ratur fluctuate from 3 @ to about 3 @ 0 ° @ and the Rücka can within the range of atmospheric pressure up to 30 or more atmospheres lie. If @@@ u @ ter des @condition en the liquid @hase works, the Tem @ rature @ fluctuate from @ to 200 ° @ and the pressure can be within the range from air pressure to 30 atm. @ d @ r higher, depending on the raw mix.

@@ e invention is explained by the following @ eis @ iel @@@@ r, that o @ sen ty @ ic operation in accordance with the aforementioned, @ recently developed @, continuous @ en @ orptio @ averfahren (part @) with an embossed operation in accordance with the provisions @rfiadung compares.

Example - Part I A raw mixture of normal hexane, hexanes with branched @ette and cyclobexane were broken down into a @product, which is made from relatively pure n-hexane and a secondary @ r @ product, @as consisted of iso- and cyclohexanes and i @ was essentially free of n-hexane, an apparatus was used that consisted of a series of 24 vertically seated, @@ each other verbu @@@ n @, festli @@@@ the beds besta @ d. The 24 beds were arranged in four sections, each with sec @@ @etten. Each section of the bed was in a stainless steel tube of 76.2 mm, of ung @ f @@ r 122 cm in length included. Each bed contained 1.77 liters of a molecular sieve sorbent, that from particles of Caloiumalumi @@@ illkat (Li @ de @ir roducts @o., 5 @ @iebe) from of irregular size in a range of sizes by 95% by weight a sieve of 5.76 mm openings and at least @@ wt .- @ on a sieve of @, 3 mm @ ffnun @ en back @@@@@ lten. Each bed has an inlet ni @@ el of reduced diameter (1 cm width) on the top and an outlet ni @ @@ l @ the same size at the bottom of each of the beds. @er @ outlet of a Bet @ es @ar the @ inlet of the next bed underneath.

@this @ created a series connected relationship between the beds @@ create. The Sorbe @@@ asse in every bed Was hung above the bed outlet through an inner screen - across the pipe. @The bottom of the 24th bed in Bor row was dunh a line with the top of the connected to the first bed and this line contained a @ un @ e for the delivery of @liquid it on the @top side of the bed under a differential pressure between the 24th and 1st bed of about 4.4 atm.

Four feed and discharge lines with a pipe diameter of 0.64 mm (one Raw mixture feed line, a refinery discharge line, a desorbent feed line and an @orbat exhaust line) were upstream and connected to a central distribution valve connected.

This distribution valve had a construction similar to that in the sch @@@ table drawing shown valve. It contained 24 openings leading through 24 lines of almost the same length are connected to the 24 fixed sorbent beds was. The connecting lines with these beds via T-pieces between the nipples connected all bed A separate trom of @ esorben @ or raw mix could so to be supplied to each bed and a separate stream of raffi @ st or sorbate could be removed from each bed by turning the valve plug, the separated one Had channels and pipes through which the fluid flows into the orbenstetten sent and removed from these.

The @exane raw mixture (40 wt .-% n-hexane, 6 @ wt .-% cyclohexane in Test run 1; 40 @ n-hexane, 60% ischexane in verification run 2, with the Ischexane eue 2-methyl @ @ ent @ n, 3-methyl @ @ ent @ n, 2,3- @ i @ ethylbutane and 2,2-dimethylbutane passed) was at a temperature of 40 ° under a pressure of 7.5 atm. in fast @r. 1 is used at a @lie @ speed of 3.8 1 per hour. In The distribution valve delivers at the same moment when the raw mixture flows ifi flett No. 1 an open channel to the opening in the valve body, which is connected to the all pipe between Beds # 6 and 7 attached to the contact column, and after about four @minutes in the stream was a backflow (@mixture of isohexa @ en in the experiment? @ Cyclohexane in run 1) which is more precisely identified below, subtracted from the outlet, that was connected to this @allrohr. If raw mix in bed @r. 1 occurred and When raffinate mixture was withdrawn from bed # 6, a stream of n-butane desorbent flowed at the same time into the desorbent inlet of the distribution valve and that was you n-butane at 40 ° o under about 6, @ atmospheric pressure. At a rate of 3.8 liters of liquid n-butane flowing per hour, the n-butane entered the contact column through the downcomer Beds no. 12 and 13, flowed downwards through the beds below, displaced previously sorbed n-hexane from the sorbent, if it is in liquid phase through the Beds flowed.

@a the desorbent stream, the df e Molakular isbsorbent particles with Previously sorbed n-hexane touched, displaced the n-butane, the sorbed n-hexane and a mixture of sorbate (n-hexane) and decorbent (n-butane) was taken from a tube subtracted, which is the outlet to bed no. l- with the sorbate inlet opening dc. Distribution valves Association. The flow of ver @ ischtem desorbent @ and n-hexane passing through the connecting line flowed through from the downpipe from bed No. 1 @ to the inlet port 19 of the valve, Sufficient to remove the net use of n-hexane in the process; the balance of the mixed sorbate desorbent setrone continued its flow through the one below Beds 19 to 24 and continued into a conduit attached to the downspout from bed # 24 which was the net draw from the bottom of the Kelonne to the top of bed # 1 in @reis directs. A @ u @@ e on the last-mentioned line increased the pressure by 3.05 Atm. Anf the outlet from the aden of the bed 24 to the pressure of 7.5 atm., that in the bed No. 1 prevailed.

The liquid stream of mixed isohexanes (pass 2) or Cyclohexane (pass 1) and n-butane desorbent passing through the connecting line of the fal @ pipe removed from bed No. 6, it was branched off to the fractionation column, the volatile n-butane desorbent from the product obtained as a bottom product stripped.

The product of runs 1 and 2 contained 97.7% cyclohexane and

@ 7.5 isohexanes and no more 2.1%% n-hexane.

The mixed desorbent n-hexanesorbate product stream from the sorbate outlet the distribution valve provided fractional distillation with sorbate products in both runs, see below for example 94% consisted of n-hexane.

The distribution valve rotated slowly but continuously. This resulted in the flow of the crude mix into bed # 1, withdrawal of @affinate Bed No. 6, flow of desorbent into bed No. 13 and withdrawal of sorbate from bed No. 13 for a period of 2.3 minutes. The flow of the relevant currents began then go into or from beds 2, 7, 14 and 1 @ in. awake 3.1 min. ii river switched off the corresponding currents in beds 1, 6, 13 and 1 @, whereby they have a remainder of the raw charge in opening 1 of the distribution valve body and in the connection line from opening 1 to bed 1. After about 57 minutes continuous operation were the @inspeislei tungraffinatauslaßdesorbensei wet and sorbate outlet streams through a full circuit of 24 beds in @er Kolenne switched on dead and the raw load begins to flow back into bed no. to start another @ cycle.

Example - Part II On the following run, the flow rates were of the various @ flows in and out of the contact column as well as the temperatures and Press on the same values as given in part @ above, held, deducted, that a modified distribution valve takes the place of the distribution valve used in Part 1 was set. The modified distribution valve was with an internal channel Pa valve plug provided that the dci first bed effluent from the bed receiving desorbents connected to the opening that was assigned to the bed, which was the raw mixture in the last @ previous stage (i.e. the first bed upstream from the bed, the raw mixture aufni @ mt). These openings were through suitable external lines and connected to a pump that generated sufficient pressure to generate an adequate one Generate flow of a desorbent-rich stream as rinsing agent @ el. So if the position of the valve plug was such that the raw feed stream entered e.g. bed # 1, became a desorbent-rich stream simultaneously through the downcomer at the bottom of the bed No. 13 withdrawn through a conduit that connects this downspout with opening 14 in the body of the distribution valve and through a valve channel, then through an external one Pump and through one Valve returned, which the flow to @opening 24 funded, which dos @trom discharged into the pipe, which was connected with the dome downpipe from Bed No. 23 was connected. The flow of the desorbent-rich stream was controlled by means of a Valves in the external line are controlled to only allow sufficient @esorbens through opening 24 and the latter opening with the pipe connecting the downpipe from bed 3 to flow to leave to last mentioned opening and conduction of in these lines as residue Raw mixture left behind from the previous stage of circulatory control before turning the lever in the distribution valve into its position into the next Rinse out stage when raw mixture entered @ bed 2 of the contact column.

Because of the backmixing between a sorbate stream (which is about 5% by volume -: Contains nantandesorbent) with the remaining raw mixture in the opening and line at the outlet side of the valve the tight doser purge flow was only clearance opening and the management of raw loading was required, for example 1.3 times the volume of fluid, l in the opening and connection line. the Amount of desorbent cleaning flow required to clear the opening and connection line at the outlet side of the valve, both of the raw mixture and the sorbate stream, io in it flowed from the other side of the valve, to be flown, was about 2.1 times that the volume of solvent in the filling and connection line.

At the same flow rates and process conditions as St. ii Example 1 were maintained and using the present modification The n-hexanesorbate product and the mixed isohexanes and cyclohexane are refined in the flow Ir @products are made in about the same @ narrow yield, but the product purities were significantly increased. The n-hexanesorbate product consisted of 99.1 while the Refinery products contained less than 0.5 wt% n-hexane.

Claims (6)

@ a t e n t a n s p r ü c h e 1. Continuous sorption process for the decomposition of a @ ohmischu @@ vo @ superplasticizers, at least one component of which selectively sorbed through @ er @hrung with a solid sorbent and its least another component is significantly less sorbed by the orbens, whereby a continuous cyclic circulation of a solvent one after the other four connected in series @ te @ experience @ zo @ en a fixed mass of a fixed Sorbass and from the exit of the last zone back to the entrance of the ers @ en @one, @ The raw mixture continuously into the circulating @ li @ ßmittel at the @@ al @ ß of the first Zone introduced, unabsorbed component continuously from the circulating probe release agent The outlet of the first zone is withdrawn, desorbents can be continuously fed into the circulating one Solvent is introduced at the inlet of the third Zas, selectively sorbed component and @ esorbe @ s continuously sucked from the outlet of the third zone and @ie four Zones @eriodic in the fixed orb mass through simultaneous switching The point of introduction of the raw mixture of the point of withdrawal of the unsorbed component the point of introduction of desorbents and the point of discharge of selectively sorbed @@ standteil u @@ desorbent each by an equal distance along the flow path of the continuously kraisenden superplasticizer are advanced, characterized in that that a @ oil flow, which consists of either 1.) a slightly in front of the components oter @.) from the selectively sorbed component the @chmixing after each dos @periodic progress through the @passage @ he led @chmix into the first zone just before the progress and then carries a product stream from the process and this pülstrom is passed through the @en @ urchlaßweg in such an amount that practically all of the raw mixture is displaced from the @ urchlaßweg in the continuously circulating fluid. 2. The method according to claim 1, characterized in that the Raw mixture from the passage through its cleaning itt of the flushing flow in one Amount equal to the substantial 1.2 to 3.5 parts of the tree in this passage way containing raw mixture is displaced. 3. The method according to claim 1 or 2, characterized in that a desorbent-rich tr @ m from a scene downstream of the insertion point of the desorbent is removed and introduced as a flushing stream into the @ passage @ path that is freed from the raw mixture su. 4. The method according to claim JI, characterized in that the flushing stream is withdrawn from the same zone into which the desorbent is being introduced. 5, the method according to any one of claims 1 to 4, characterized ge. indicates that in the decomposition of a raw mixture, which essentially ra s hydrocarbons ii t @ at least one straight hydrocarbon and at least one hydrocarbon of branched chain or cyclic structure, with an orbens, whose Pores are able to charge straight-chain hydrocarbons to o @@ while the other hydrocarbons of the deer mixture are excluded from the Deer mixture to be freed passage way is cleaned with a pülstrem, the mindestans predominantly from a straight-chain hydrocarbon boiling below this raw mixture consists. 6. The method according to claim 3r, characterized in that at sr Breakdown of a raw mixture of normally liquid hydrocarbons with at least one straight-chain paraffin in admixture with at least one link the group, the paraffins with branched chain and cycloparaffins in a Dra @ k, in which the raw mix is kept in the liquid phase, that of the raw mix The passageway to be cleared is cleaned with a @ rinsing agent, which is at least prevalent consists of @ormalbutane and is passed through the passage in the liquid state will.