Industrial processes Mond process

As mentioned earlier, nickel carbonyl is a volatile intermediate in the Mond process for nickel refining. This compound also is used for vapor plating of nickel in the semiconductor industry, and as a catalyst in the chemical and petrochemical industries. The toxicity of the compound has been known for many years Exposure of laboratory animals to the compound has induced a number of ocular anomalies, including aiioplidialiiiiaandinicrophtlialmia, and has been shown to be a carcinogenic for rats. 

Nickel carbonyl, an intermediate in the Mond process for nickel refining, is also used for vapor-plating in the metallurgical and electronics industries and as a catalyst for synthesis of acrylic monomers in the plastics industry. Inadvertent formation of nickel carbonyl can occur in industrial processes that use nickel catalysts, such as coal gasification, petroleum refining, and hydrogenation of lipids. 

Nickel carbonyl is prepared in this experiment, since it is the easiest of the carbonyls to prepare, no high pressure being needed, and is of industrial importance in the Mond process for the purification of nickel. 

The reaction above forms the basis of an important industrial process called the Mond process for obtaining nickel metal from its oxides. In the Mond process, CO(g) is passed over a mixture of metal oxides. Nickel is carried off as Ni(CO)4(g), while the other oxides are reduced to the metals. When Ni(CO)4(g) is subsequently heated to about 250 °C, the carbonyl complex decomposes, yielding Ni(s). With iron, it is necessary to use higher temperatures (200 °C) and CO(g) pressures (100 atm). 

Carbon monoxide very readily forms coordination compounds, particularly with transition metals in low oxidation numbers. One important industrial use of these compounds is found in the Mond process for purifying nickel (developed by L. Mond in 1899). The impure metal is treated with CO to give the volatile carbonyl compound, nickel tetracarbonyl, Ni(CO)4 (Structure 10.2). The Ni(CO)4 vapour is subsequently decomposed at higher temperature to give pure nickel. 

Imperial Chemical Industries PLC, Explosion Hazards Section, Technical Department. The Mond Index How to Identify, assess and minimize potential hazards on chemical plant units for new and existing processes. Second Edition. Winnington, Northwich Cheshire. 

Ludwig Mond. The Origins of the Ammonia-Soda Process. Journal of the Society of Chemical Industries. 4 (1885) 527-529. 

Process industry has used the Dow Fire and Explosion Hazard Index (DOW, 1987) and the Mond Index (ICI, 1985) for many years. These indices deal with fire and explosion hazard rating of process plants. Dow and Mond Indices are rapid hazard-assessment methods for use on chemical plant, during process and plant development, and in the design of plant layout. They are best suited to later design stages when process equipment, chemical substances and process conditions are known. 

Health hazards caused by chemicals are represented by the Toxic Exposure Subindex (ITox). hi the ISI the evaluation of toxic exposure is based on the Threshold Limit Values (TLV) because TLV data is readily available for most substances in process industry. TLV values express the harmful exposure limits of substances in the threshold time of 8 hours. The index value is higher, when the TLV is lower i.e. the substance is more toxic. It is important to use TLVs with same threshold time so that the results are comparable. Score limits in Table 13 are based on Mond Index (ICI, 1985). 

Producer Gas.—The ammonia contained in the coals used in producing this gas—the main type of plant used being the Mond Gas Producer—is now very large and is likely to increase. The process is described in Martin s Industrial Chemistry, Vol. II. 

One of the earliest industrial CVD applications developed during this stage is a carbonyl process for refining nickel (Ni), developed by Mond in 1890 [9, 10], The famous Mond extraction process uses the following chemical reaction process ... 

The ICI-MOND Fire Explosion and Toxicity Index (ICI 1985) was derived from DOW one and it is yet appreciated in process industry in many countries, including Italy. In ICI-MOND index method there are some ninety elementary questions, nested in a three levels tree. For many issues there is also a forth level of nested questions. About two thirds of the questions are for penalties and one third for credits accounting. For the most of the questions a quantitative answer is required. The questions are organized in chapters for penalties section the subjects are related to materials and quantities, processes and equipment, layout, health for credits section instead the method deals with containment, control, safety culture, fire engineering and emergency preparedness. Every issue weighs differently in overall risk levels accounting. Results are presented in a structured way, discriminat-iug fire, toxic, confined and unconfined explosion. 

ICI (Imperial Chemical Industries). Formed in 1926 by the amalgamation of four major chemical companies, including British Dyestuffs (Kollewe and Wearden, 2007). Two of the other organizations, Brunner Mond and United Alkali, already produced alkalis used as basic components for many chemical processes, particularly washing and dyeing textiles. The last of the four companies, Nobel Industries was founded by Alfred Nobel (of the Nobel Peace Prize) and manufactured explosives. 

Metal carbonyls are compounds of transition metals with carbon monoxide ligands. They find applications in many catalytic processes and in organic synthesis. Thus, research on preparations, structures, and applications of metal carbonyls and their derivatives has been intensive for several years. The first metal carbonyl, Ni(CO)4, was prepared by A. Mond, G. Langer, and F. Quincke in 1890 by the reaction of metallic nickel with carbon monoxide. It found application immediately it has been used for industrial preparation of pure nickel. Many other carbonyls were synthesized shortly thereafter. 

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