Cracking processes reforming, thermal

There are mainly three methods for pyrolysis of plastics, namely thermal cracking, catalytic cracking, and cracking-catalytic reforming [62]. Each has its own suitable process, as shown in Figure 28.2. Other methods for plastics pyrolysis include hydrogenation... 

These, along with the molecule degradation and reformation processes of thermal and catalytic cracking e.g. ... 

While many studies have been carried out aimed at the feedstock recycling of rubber wastes by pyrolysis and hydrogenation processes (see Chapters 5 and 7), little information is found on the catalytic cracking and reforming of rubber alone. Larsen35 has disclosed that waste rubber, such as used tyres, can be degraded in the presence of molten salt catalysts with properties as Lewis acids, such as zinc chloride, tin chloride and antimony iodide. The decomposition proceeds at temperatures between 380 and 500 °C to yield gases, oil and a residue, in proportions similar to those obtained by simple thermal decomposition. 

The chemical reactions involved in the production of the foregoing chonicals include petroleum reforming, thermal or catalytic cracking, oxidation, alkylation, ddiydrogmation, hydration, and chlorination. Most processes use proprietary catalysts to increase product yield and to reduce severe operating conditions and pollution. Water is used extensively both in the process and for cooling purposes. 

The main types of feedstock recycling processes can be summarised as chemical depolymerisation, gasification and partial oxidation, thermal degradation, catalytic cracking and reforming, and hydrogenation [852663]. The current advanced thermal treatments are as follows [a.372]. 

Phases of processing other than heavy-oil distillation processes are discussed in many chapters, particularly under treating (Chaps. 10-11), dewaxing (Chap. 12), thermal cracking (Chap. 19), chemical manufacture (Chap. 20), catalytic cracking and reforming (Chap. 21), and natural gasoline (Chap. 22). 

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