Material Production from Carbon Dioxide

The potential release of the toxic BPA from the polymer is driving the search for an alternative monomer. Diphenolic acid (DPA) is a potential substitute for BPA in polymer synthesis. The synthesis of polycarbonates involves a two-step process. First, DPA is treated with NaOH to produce a sodium diphenoxide. This intermediate reacts with phosgene (COCy to start the polymerisation. A disadvantage of this process is the toxicity of phosgene (phosgene was used as a chemical weapon during World War 1). An alternative route to polycarbonates consists of the transesterification of DPA with diphenyl carbonates. DPA can also be copolymerised using the same reaction route. 

Despite the potential replacement of the toxic BPA by the less harmful and bio-based DPA, the synthesis route uses the harmful reactant phosgene. Thus, alternatives are being explored for the production of novel polycarbonates (Sadhukhan et al. 2014). A route promising various environmental advantages comprises the use of CO for carbonate product. This route eliminates the need for phosgene and BPA. In addition, CO is captured in a durable polymer, and CO is less expensive than phosgene. 

3 Process Systems Engineering Tools for Carbon Dioxide Capture and Reuse 

This section discusses the techno-economic analysis tools in Section 9.3.1 and CO pinch analysis, targeting and exchange network design tools in Section 9.3.2 using suitable examples. 

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Gas Flow Rate. The model can be extended to consider all five desired variables, and the restriction of a constant partial pressure of carbon dioxide can be removed by developing material balances for carbon dioxide in both the liquid and gas phases. The material balance on dissolved carbon dioxide is shown in Equation 25. Rb is the rate of production of carbon dioxide from the substrate by the methane bacteria and Rc is the rate of production of carbon dioxide from bicarbonate. The reaction of substrate and bicarbonate to produce carbon dioxide is given in Equation 28. 

For 40 years, energy consumption has increased by more than 40%, and the development of emerging countries accelerates this trend, which raises two main problems the scarcity of raw materials oil, coal and gas and the production of carbon dioxide, which contributes to chmate change. The production of primary energy is at the beginning of this century based on fossil fuels, as shown in Figure 1.3, extracted from lEA statistics for 2008. 

Starch is one of the most abundant polysaccharides in nature. It is synthesized as a result of the photosynthesis process from carbon dioxide and water, and is then accumulated in seeds, tubers, and other parts of the plant [1,46], The primary raw material for starch production in the worldmarket is maize (81% of the global production of starch). Lesser, though significant, importance in this case is shared by wheat and potato (9 and 5% of global production, respectively). On the industrial scale, tapioca, rice, and waxy maize are also used. The total production of starch does not exceed 5% [11,89,91]. The global production of starch in the year 2(X)5 reached about 60 million tons [89]. 

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