Copper pyrophosphate

Thermal polymerization is not as effective as catalytic polymerization but has the advantage that it can be used to polymerize saturated materials that caimot be induced to react by catalysts. The process consists of the vapor-phase cracking of, for example, propane and butane, followed by prolonged periods at high temperature (510—595°C) for the reactions to proceed to near completion. Olefins can also be conveniendy polymerized by means of an acid catalyst. Thus, the treated olefin-rich feed stream is contacted with a catalyst, such as sulfuric acid, copper pyrophosphate, or phosphoric acid, at 150—220°C and 1035—8275 kPa (150—1200 psi), depending on feedstock and product requirement. 

Phosphates are the principal catalysts used in polymerization units the commercially used catalysts are Hquid phosphoric acid, phosphoric acid on kieselguhr, copper pyrophosphate pellets, and phosphoric acid film on quartz. The last is the least active and has the disadvantage that carbonaceous deposits must occasionally be burned off the support. Compared to other processes, the one using Hquid phosphoric acid catalyst is far more responsive to attempts to raise production by increasing temperature. 

Copper Pyrophosphate. Baths using copper pyrophosphate [10102-90-6] shown in Table 9, are not in wide use in the United... 

Copper and compounds SPA Copper sulphate Copper pyrophosphate Cuprammonium compounds Electroplating Electrical and electronics Etching Pesticides... 

Metal salts in alkaline solution Cuprammonium complex Nickel and cobalt ammonia complex Cyanides (q.v.) Copper pyrophosphates Plumbites Zincates... 

Copper sulphate Copper pyrophosphate Cuprammonium compounds... 

Polyco A process for converting propylene and butene to liquid fuels, using copper pyrophosphate as the catalyst. The name has also been used as a trade name for a type of polyvinyl acetate made by the Borden Chemical Company. 

Copper plating, 9 764, 766, 804-807 Copper pollutants, 9 443-444 Copper pyrophosphate deposition, 9 809 Copper recovery... 

Orthophosphoric acid and pyrophosphoric acid are preferred catalysts. Phosphorus pentoxide is catalytically active but no conclusive evidence has been described to show whether or not its activity depends on the presence of traces of water as promoter. Copper pyrophosphate and acid phosphates of cadmium are also good catalysts that the former probably owes its activity to partial conversion to acid or acidic salt under the polymerization conditions seems to be shown by the fact that there is an induction period. A composite prepared by calcining kiesel-guhr impregnated with orthophosphoric acid (the so-called solid phosphoric acid ) has found wide commercial use. 

The polymerization of light olefins using copper pyrophosphate is licensed by The M. W. Kellogg Co. under patents of the Polymerization Process Corp. The process is essentially the same as the U.O.P. process but instead uses a copper pyrophosphate catalyst (18). The first plant was built in 1939 (22) and several more have been put into operation since that time. A correlation of operating variables for this process was published in 1949 (21) it shows how conversion is influenced by catalyst activity, temperature, ratio of propene plus n-butene to isobutene, and the space velocity of olefins and of total feed when operating at 900 pounds per square inch gage pressure. A catalyst life of 100 to 150 gallons of polymer per pound of catalyst is claimed (15). 

Copper Pyrophosphate Copper pyrophosphate Potassium hydroxide Ammonia... 

Gardiner and Casey [65] observed the radicals Of, Of, and MOf, which are formed on various electrode surfaces during oxidation processes on different materials in KOH solutions. Studies of copper dissolution in pyrophosphate [66] resulted in polymeric copper pyrophosphate complexes. 

When cumene is to be used as a raw material for the production of nylon, the cumene must be very pure with a bromine number of 0.2 or lower. Although liquid phosphoric acid has been used as a catalyst to make cumene, it has the disadvantage in that it is necessary to acid treat the product to reduce the bromine number of the cumene to the 0.2 level. Some cumene is also lost in the acid treating step. Copper pyrophosphate catalyst has also been used but corrosion of the equipment has been experienced, resulting in longer than average downtime. 

When thermal cracking was the predominant method of making cracked gasolines, a copper pyrophosphate catalyst (1) was used to some... 

The copper pyrophosphate catalyst is poisoned by sulfur compounds in addition to those mentioned above. 

The Copper Pyrophosphate Catalyst was developed for use in the Kellogg polymerization units. These units are similar to the two U.O.P. types with the following exceptions ... 

New Copper Pyrophosphate Catalyst requires an activating period before satisfactory olefin conversion can be obtained. This activating period may range up to 1 or 2 days, a factor which requires additional plant capacity if high conversions are required during these periods. 

Olefins can also be conveniently polymerized by means of an acid catalyst. Thus, the treated, olefin-rich feed stream is contacted with a catalyst (sulfuric acid, copper pyrophosphate, phosphoric acid) at 150 to 220°C (300-425°F) and 150-1200 psi (10-81 atmospheres), depending on the feedstock and product requirement. 

Pyrobrite [ATOTECH]. TM for a bright-leveling, pyrophosphate copper electroplating process. The materials used are copper pyrophosphate trihydrate, potassium pyrophosphate, ammonium hydroxide, and addition agents. 

Copper pyrophosphate (electrolytical) Determination of ammonium, orthophosphate, and nitrate... 

An important constituent in copper pyrophosphate baths is nitrate, which enhances the maximum permissible current density [31]. Fig. 8-30 shows the respective chromatogram with the separation of nitrate and orthophosphate. The latter is the hydrolysis product of pyrophosphate that is formed during the plating process. The main component pyrophosphate may also be separated on a latexed anion exchanger. It is detected after complexation with ferric nitrate in a post-column reaction by measuring the light absorption (see Section 3.3.5.2). 

Fig. 8-30. Analysis of mineral acids in a copper pyrophosphate bath. -Separator column IonPac AS3 eluent 0.003 mol/L NaHC03 + 0.0028 mol/L Na2C03 flow rate 2.3 mL/min detection suppressed conductivity injection 10 pL sample (1 1000 diluted).

While alkali and alkaline-earth metals can also be rapidly and very sensitively detected by other instrumental analysis methods, the advantage of ion chromatography lies in the simultaneous detection of the ammonium ion. In copper pyrophosphate baths, for example, the addition of ammonia improves the plating evenness. However, as the ammonia concentration continuously decreases at higher bath temperatures, it must be added to maintain optimal bath conditions. As seen in Fig. 8-40, after separation on an anion exchanger the ammonium ion can be detected quickly and reliably separated from sodium and potassium. 

J.W. Dini. In F.A. Lowenheim (ed.). Copper Pyrophosphate Plating in Modem Electroplating. John Wiley Sons, New York 1984 p. 204-223. 

---