Butadiene recovery processes

A separation process is sought that can satisfy both our present economic and enviromental constraints. It would also provide an alternative to present practice that relies on expensive azeotropic or extractive distillation processes used in the recovery of products from low relative volatility streams. As an example, virtually all industrial butadiene recovery processes now rely on extractive distillation using acetonitrile or other equivalent agent to enhance the relative volatility of the C4 components. The use of supercritical or near critical separation of these streams may satisfy these requirements provided certain pressure, temperature and recompression criteria can be met. Such a process would also reduce the need for a complex train of distillation towers. 

Coogkr, W. W Butadiene recovery proems employs new solvent system"/ Chem. Engng, 74(16) 70-72(1967) Thomas. E- H "DMAC butadiene recovery process offers many advantages. Europ. Chem. Sews. Large Plant SuppL 62-64127 Sept. 1968). 

Troublesome amounts of C and Q acetylenes are also produced in cracking. In the butadiene and isoprene recovery processes, the acetylenes in the feed are either hydrogenated, polymerized, or extracted and burned. Acetylene hydrogenation catalyst types include palladium on alumina, and some non-noble metals. 

Process Evaluation of Improved Solvents for Butadiene Recovery... 

Klein. H, Weitz, H. M, Extract butadiene with NMP", Hydrocarbon Processing, 47 (11) 135-138 (1968) Reis, T, Compare butadiene recovery method, processes, solvents/economra",- Petro/Chem Engng, 41 (8) 12-22(1969)... 

Figure 3-16. Flow diagram of the Lummus process for producing butadiene (1) reactor, (2) quenching, (3) compressor, (4) cryogenic recovery, (5) stabilizer, (6) extraction.

This comprehensive article supplies details of a new catalytic process for the degradation of municipal waste plastics in a glass reactor. The degradation of plastics was carried out at atmospheric pressure and 410 degrees C in batch and continuous feed operation. The waste plastics and simulated mixed plastics are composed of polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylonitrile butadiene styrene, and polyethylene terephthalate. In the study, the degradation rate and yield of fuel oil recovery promoted by the use of silica alumina catalysts are compared with the non-catalytic thermal degradation. 9 refs. lAPAN... 

Two important extractive distillation processes were placed in commercial operation during World War II the recovery of butadiene from a C4 fraction using furfural as the entrainer (7, 22) and the segregation of toluene from petroleum fractions by means of phenol (14-16). 

For the purposes of the F EI Guide a process unit is defined as any primary item of process equipment. For example, in the process area of a styrene/butadiene latex plant, process units could include monomer mix feed preparation, reactors, stripppers, monomer recovery, aqueous room, and styrene scrubber. A warehouse also may be treated as a process unit. In particular, materials stored within a fire-walled area, or within the total storage area where fire walls are not provided, would constitute such a process unit. 

The superior properties of polypropylene terephthalate) (PPT) polymer and fibers over the chemically analogous poly(ethylene terephthalate) (PET, used for soda bottles) and poly(butylene terephthalate) (PBT) have been well known for several decades PPT fibers are much more elastic and less brittle than PET and offer better recovery from stretching than PBT they are also easier to dye than either PET or PBT. Compared to the intermediate for PET, ethylene glycol, which is available inexpensively from ethylene oxide, and to that for PBT, butanediol, likewise available inexpensively from butene or butadiene, the intermediate for PPT, 1,3 propanediol (1,3-PPD or PDO), was not - and on a large scale is still not - available. Three processes, two chemical ones and one biotechnological, compete to change this situation (Figure 20.10). 

Yields This process can exceed 98% recovery of the butadiene contained in the feed as product. This product will meet all butadiene derivative requirements with typical specifications shown below. 

Yields The combination of the KLP process with butadiene extraction can provide over 100% recovery of the butadiene contained in the feed as product. The recovery is enhanced by the conversion of vinylacetylene to 1,3-butadiene. Total acetylene levels in the product of less than 10 wt-ppm are achievable. The process also offers improved safety in operations by eliminating concentrated acetylene byproduct streams. 

Section, which appears every month. It also has a special section on Patents which lists new patents according to their classification. The Process Issue of the Petroleum Refiner is now carrying a special section on Petrochemical Processes. In the September 1952 issue for example, Extractive Distillation for Aromatic Recovery, Modified SO2 Extraction for Aromatic Recovery, Udex Extraction, Ethylene Manufacture by Cracking, Ethylene Production, Hypersorption, Hydrocol, Dehydrogenation (for butadiene), and Butadiene Process, were described. These descriptions include the main essentials of the process, simplified flow diagrams, and the name of the company offering it. Formerly these processes were described under the Process Section. 

The addition of HCN to C=C double bonds can be effected in low yields to produce Markovnikov addition products. However, through the use of transition metal catalysts, the selective anti-Markovnikov addition of HCN to alkenes can take place. The most prominent example of the use of aqueous media for transition metal-catalyzed alkene hydrocyanation chemistry is the three-step synthesis of adi-ponitrile from butadiene and HCN (Eqs. 5-7). First discovered by Drinkard at DuPont [14], this nickel-catalyzed chemistry can use a wide variety of phosphorus ligands [15] and is practiced commercially in nonaqueous media by both DuPont and Butachimie, A DuPont/Rhone-Poulenc joint venture. Since the initial reports of Drinkard, first Kuntz [16] and, more recently, Huser and Perron [17, 18] from Rhone-Poulenc have explored the use of water-soluble ligands for this process to facilitate catalyst recovery and recycle from these high-boiling organic products. 

Organic iodine recovery is less of a problem in a propylene process than in a butadiene process. Diiodobutene polymerizes in the quenching section, and methyl iodide-butadiene separation is difficult. 

Beilstein Handbrjok Reference) AI3-28026 BRN 1731349 CCRIS 964 Diethylhydroxyl-amine N,N-Diethylhydroxyamine EINECS 223-055-4 Ethanamine, N-ethyl-N-hydroxy- Hydroxylamine, N,N-diethyl- N-Hydroxydiethylamine Pennstop 1866. Free radical scavenger used by the rubber industry as an emulsion polymerization inhibitor vapor phase inhibitor for olefin or styrene monomer recovery systems in-process inhibitor for production of styrene, divinyl benzene, butadiene and isoprene. Liquid mp = 10° bp = 133° d = 0.8669. ElfAtochem N. Am. 

---