Chemithon reactor

Chemithon film sulfonating-sulfating systems, 23 544-547 Chemithon reactor, 23 544 Chemoinformatics, 6 1-25 chemical databases, 6 19-20 chemical information retrieval, 6 6—19 chemical information storage, 6 2-6 chemical library design, 6 17-18 clustering techniques, 6 16-17 conformational flexibility, 6 10-11 conformational searches, 6 10-11 data analysis and preparation, 6 20-21 data searching, 6 6-19 diversity searches, 6 14-18... 

The reactor is of the thin annular falling-film type, similar to the Chemithon reactor. It has a short length of about 2 m and a diameter of typically 0.3 to 1.0 m, depending on the capacity of the reactor. The width of the annulus through which the liquid film flows is about 5.5 to 30 mm. At the base of the film reactor, the reaction mixture is immediately quenched with an excess of... 

After the SO converter has stabilized, the 6—7% SO gas stream can be further diluted with dry air, I, to provide the SO reaction gas at a prescribed concentration, ca 4 vol % for LAB sulfonation and ca 2.5% for alcohol ethoxylate sulfation. The molten sulfur is accurately measured and controlled by mass flow meters. The organic feedstock is also accurately controlled by mass flow meters and a variable speed-driven gear pump. The high velocity SO reaction gas and organic feedstock are introduced into the top of the sulfonation reactor,, in cocurrent downward flow where the reaction product and gas are separated in a cyclone separator, K, then pumped to a cooler, L, and circulated back into a quench cooling reservoir at the base of the reactor, unique to Chemithon concentric reactor systems. The gas stream from the cyclone separator, M, is sent to an electrostatic precipitator (ESP), N, which removes entrained acidic organics, and then sent to the packed tower, H, where SO2 and any SO traces are adsorbed in a dilute NaOH solution and finally vented, O. Even a 99% conversion of SO2 to SO contributes ca 500 ppm SO2 to the effluent gas. 

The Chemithon falling film monotube reactor with subsequent quench loop reactor... 

Annular film reactor, Chemithon, 23 547 Annular flow, 11 772 Annular shaft kiln, 15 48-49 Annulenes, 12 243 Anode(s)... 

Film reactors, Chemithon, 23 544-547 Film reactor systems, 23 544 Film rupture, 12 14 Film sharpness, in color photography, 19 264-265... 

The Chemithon Corporation has patented a novel venture reactor.34,35 The organic to be sul-fonated is injected into a stream of gas containing S03 at a venture. The reaction mixture is quenched and recycled downstream until sulfonation is complete. The reactor design can be used for highly viscous, high molecular weight specialty surfactants for industrial applications such as lubrication oil additives. 

Chemithon impact jet reactor Atomises organic feed in S03/air... 

Chemithon falling film reactor Falling film reactor... 

Stepan was the first to develop and conunercialize a continuous falling film SO3 sulfonation process. The design is a multitubular unit. The company operates about 12 falling film SO3 sulfonation units in the United States, not only for the production of linear alkyl benzene sulfonates, but substantial amounts of fatty alcohol and fatty alcohol ethoxylates are also sulfated. Other key commercial reactor designs are by Chemithon, Ballestra SpA, Lion, Mazzoni SpA, and Meccaniche Modeme. Several features are common to all falling-film systems. Fatty alcohol and alcohol ethoxylates are reacted at a rate of about 0.3 kg/h/mm with SO3 concentration at about 2-3%. Liquid residence times are estimated at 10-30 s and most units operate with gas velocities in the range of hurricane wind velocities (121-322 km/h). ° Linear alcohols and linear alcohol ethoxylates are by far the easiest to sulfate. Caution is required with branched alcohols as color and conversion can suffer. 

It should be noted that continuous sulfation is widely used today, with the mixture of SOj/air in reactors such as Chemithon, Allied, or Ballestra. Moreover, alcohol sulfates are preferably used in alkaline formulations because of their low stability in acid medium. However, they are completely biodegradable and compete with petrochemical-derived linear alkylbenzene sulfonates (LAS). 

There are seven main sulphonation reactor systems used world-wide for SOs/air sulphonation for which there is proven practical and documented experience The Ballestra Sulphurex continuous stirred tank reactor (CSTR) cascade, the Ballestra Sulphurex F (a multitube falling-film reactor (MT-FFR)) the Chemithon falling-film reactor (FFR), the Chemithon Jet Impact Reactor, the MM falling-film reactor (FFR), the Mazzoni Sulpho film reactor (a multitube falling-film reactor) and the Japanese T-0 FFR reactor system. 

This compares with a gap of 16.5 mm on the MM reactor. It means that with the same organic load of 0.4 kg/mm circumference per hour and the same SO3 levels in air, the gas velocity in the Chemithon film part will be about double the MM values, say 80 m/s at 3% SO3 in air and 48 m/s at 5% SO3 in air, i.e. the SO3 flux to the interface will be roughly double the amount as compared with the other film reactors discussed. 

Co-current flow of the organic feedstock and the SOj/air is realised in all falling-film reactor types and the Chemithon Jet Impact Reactor. 

The pure falling-film reactors will have the shortest residence time, order of magnitude 30 seconds. The Chemithon FFR and Jet Impact Reactor, both with quench loop, could have an organic liquid residence time of about 2 to 5 minutes, depending on the liquid level in the de-gassing tank. Finally the Ballestra CSTR system shows a total residence time for the organic liquid of the order of 60 minutes. 

The Ballestra Sulphurex CSTR system is relatively simple in its mechanical construction. The same can be said about the Chemithon Jet Impact Reactor. Film reactors are mechanically more sophisticated constructions, notably the organic liquid distribution systems. The delicate FFRs can not always be recommended for countries where the level of technology and maintenance is low. 

The Ballestra Sulphurex CSTR and the Chemithon Jet Impact Reactor are usually only used for simple feedstocks like alkylbenzene. 

Table 23 Final product specification for Chemithon Jet Impact Reactor...

For purposes of reducing 1,4-dioxane, control of the mole ratio was found to be a much broader concept than simply ratioing reactants to the reactor. The mole ratio had to be controlled at all points in the reactor. This means that the organic films in the reactor have to be controlled so that they are of equal thickness (mass) at each circumferential cross-section of the reactor. The gas flow has to be controlled so that it is uniform at all points around the reactor circumference. In addition, the organic film has to be introduced into the reactor so that organic mist does not form. To accomplish this, Chemithon developed a new precise organic distribution system to ensure liquid film uniformity ( 0.5%) on the reactor surfaces. The reactor geometry provides the gas flow control required to ensure uniform SO3 gas supply to all points in the reactor. 

Higher gas velocities at a fixed SO3 concentration in the Chemithon-design film reactors reduced 1,4-dioxane levels. The higher gas velocities achieved this result by reducing the reactor residence time of the organic phase in the falling-film part (residence times of 10 seconds or less) and by improving the heat and mass transfer rates in the reactor. 

Mazzoni sulfonic acid neutralisation Mazzoni three stage neutralisation reactor Chemithon neutralisation system Chlorine dosing equipment Alpha-olefin hydrolysis equipment ESP construction details Details of wire hanging mechanics Points of wire failure... 

Final product specification for Ballestra sulphurex CSTR sulphonation system Final product specification for Ballestra multi-tube falling-film reactor (MT-FFR) Final product specification for Chemithon falling-film reactor system (FFR)... 

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