Reppe alcohol synthesis

The Reppe alcohol synthesis fi om olefins and CO/H2O with hard iron/amine catalysts can be explained analogously the end products are almost exclusively alco-... 

A reaction closely related to olefin hydroformylation is the Reppe alcohol synthesis [239, 1003]. It is carried out in alkaline media with Fe(CO)5 catalyst and differs from the Roelen reaction in that water is used instead of hydrogen, with the result that alcohols are obtained directly at lower temperatures. The active catalyst is believed to be a salt of the iron hydrocarbonyl. 

The Reppe alcohol synthesis (see page 40) is technically applied in Japan by the Japan Butanol Co. Ltd. in Yokkaichi under license of BASF with a capacity of 15,000 tons/year [1003, 1004, 1014]. Operating conditions are 100 °C and 15 atm. A butanol yield of 90 % is reported which consists of 85 % of n- and 15 % of iso-butanol. 

The reaction between formaldehyde and acetylene is exothermic M = -100 kJ/mol) and the control of temperature is critical. To solve this problem it has been chosen to limit the temperature increase by injecting cold acetylen at different levels in the bed (T) This arrangement with the flowsheet of the Reppe s synthesis of butynediol is shown on Figure Propargyl alcohol is formed according to the following equation ... 

Acetylene-Based Routes. Walter Reppe, the father of modem acetylene chemistry, discovered the reaction of nickel carbonyl with acetylene and water or alcohols to give acryUc acid or esters (75,76). This discovery led to several processes which have been in commercial use. The original Reppe reaction requires a stoichiometric ratio of nickel carbonyl to acetylene. The Rohm and Haas modified or semicatalytic process provides 60—80% of the carbon monoxide from a separate carbon monoxide feed and the remainder from nickel carbonyl (77—78). The reactions for the synthesis of ethyl acrylate are... 

Even if new processes of synthesis were developed from alcohols, like catalytic vinylation with ethylene or vinyl exchange with vinyl acetate, the major commercial route for VE monomers seams to be still the Reppe method based on reaction, in basic conditions, of acetylene with the corresponding alcohols [96,97,100] ... 

A great variety of reactions with CO are known and have gained industrial importance. Best known is the Roclen-synthesis (hydroformylation or 0x0-synthesis) by whicli about 5 million tons of aldehydes, acids and alcohols are synthesized worldwide. But also carbonylailons (Reppe reaction) are practised in many plants. Carbonylations are those reactions in which CO. alone or together with other compounds, is introduced into particular derivatives exemplified in the following reactions ... 

The synthesis of carboxylic acids by carbonylation of unsaturated hydrocarbons or alcohols was developed mainly by Reppe and his co-workers in the laboratories of BASF at Ludwigshafen. Many industrially important processes such as the synthesis of acrylic acid, propionic acid, and acetic acid were elaborated there in the period from the late 1930s to the mid-1950s [1, 2]. Reppe s introduction of metal carbonyls as catalysts for carbonylation reactions was of paramount importance and many processes, which are still industrially relevant today, were developed rapidly (eq. (1), [3]). 

Commercial petrochemical processes using syngas or carbon monoxide are based on four principal classes of reactions phosgenation, Reppe chemistry, hydroformylations, and Koch carbonylations. Phosgenation is a key step in the manufacture of polyurethanes, polycarbonates, and monoisocyanates. Reppe chemistry is the basis for acetic acid and acetic anhydride production as well as formic acid and methyl methacrylate synthesis. Hydroformylations utilize syngas in the oxo synthesis to make a wide variety of aldehydes and long-chain alcohols. The fourth class of reactions are Koch carbonylations. Koch carbonylations are used commercially to produce neo acids which are specialty products that serve markets similar to 0X0 alcohols. 

Walter Reppe also used his new base to expand the chemistry of acetylene. His first major breakthrough, in the summer of 1939, was the addition of carbon monoxide to acetylene in the presence of alcohols (or water) and a nickel catalyst to form acrylates. Carbon monoxide had attracted attention for many years as a readily available, cheap and reactive carbon compound. I.G. Farben employed it in the Pier methanol synthesis, Ruhrchemie used it in the Fischer-Tropsch synthetic petrol process, and Du Pont had carried out research on the addition of carbon monoxide to olefins at very high pressure and temperatures. Additional impetus for the use of carbon monoxide in acetylene chemistry was provided by the introduction of covered carbide furnaces at I.G. Farben s Knapsack plant in 1938, which permitted the collection of by-product carbon monoxide. The polymers of acrylic esters were already used for treating leather and for paint, but acrylic acid was made from ethylene oxide, and consequently was rather expensive. Reppe s process reached the pilot plant stage by 1945, and was subsequently used on a large scale by BASF and its American partners. 

Acrylic ester synthesis from acetylene, carbon monoxide, and alcohols with the aid of nickel carbonyl is known as the Reppe synthesis and is very important in industrial applications (Reppe, 1953). This carboxylation re-... 

The oldest, most versatile, and major commercial method for the synthesis of vinyl ethers is by the base-catalyzed condensation of acetylene with alcohols first described by Reppe and co-workers [11-13]. 

Actual operating capacities of Reppe carbonylation processes are difficult to estimate since only a few data are available in the literature. However, it is known that some of the syntheses are carried out on an industrial scale, e. g. the synthesis of acrylates from acetylene, carbon monoxide and alcohols (BASF) [1004, 1005], the acetic acid synthesis from methanol and carbon monoxide and the synthesis of higher molecular weight saturated carboxylic acids from olefins, carbon monoxide and water. Propionic acid (30,000 tons/year) and to a smaller extent heptadecanoic dicarboxylic acid are manufactured via the carbonylation route at BASF. Butanol is made from propylene in Japan [1003, 1004]. 

Industrially, large quantities of vinyl ethers can be prepared following Reppe s ethynylation reaction that involved reacting acetylene gas with alcohols [101]. Due to the challenges and hazards associated with the experiment as well as the required handling of acetylene gas (under pressure) alternative approaches to the synthesis of vinyl ethers are typically used in small laboratory settings. One such approach used common iridium complexes to catalyze... 

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