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Carbon capture and sequestration (CCS) refers to procedure for capturing and
storing CO 2 emitted from industrial processing of fossil fuels, power plants, and
product manufacturing sectors, thereby inhibiting its release into the atmosphere.
Nanda et al. (2016b) reviewed numerous routes existing for CO 2 capture from
industrial flue gases such as physicochemical, geological, and biological routes. The
physicochemical routes include absorption, membrane-based gas separation,
adsorption, and cryogenic distillation to separate and capture CO 2 in flue gas effluents (Yu et al. 2012). Moreover, the geological routes involve long-term storage of
CO 2 under the oceans and its mineralization to form carbonates in seawater (Khoo
and Tan 2006). The geological route is also related to the amendment of biochar
generated from thermochemical conversion of organic wastes into the soil to sequester the carbon for centuries as evidenced from the Amazonian terra preta (Nanda
et al. 2016a). On the other hand, the biological routes involve eco-friendly
approaches such as biological carbon fixation by algae and energy crops. The plants
utilize and fix CO 2 during photosynthesis to form carbohydrates (terrestrial plants)
and polysaccharides (algae). These polysaccharides and carbohydrates could be
potentially converted into fuels, chemicals, and hydrocarbons through thermochemical, i.e., pyrolysis, gasification, and liquefaction; biochemical, viz., fermentation
and methanation; and photocatalytic conversion approaches (Nanda et al. 2014).
Therefore, the biofuels are considered carbon-neutral as CO 2 emitted from biofuels
combustion is consumed by plants via photosynthesis (Nanda et al. 2013).
As mentioned earlier, through many physicochemical technologies such as
absorption and adsorption, CO 2 can be separated and captured from the industrial
emissions. However, the potential utilization of this captured CO 2 is highly imperative to account for sustainability. Since CO 2 is a major greenhouse gas, it is always
looked upon as an adversative component. The many versatile industrial utility of
CO 2 is rarely acknowledged in the literature. Realizing the perceptible carbon
sequestration projects worldwide and the massive amounts of CO 2 captured, its utilization for value-added products could attribute to a sustainable and circular economy. In simple words, the CO 2 captured from industrial flue gases can be the
potential raw material for commercial chemical and fuel industries (Jiang et al.
2010). This opens up the new concept of carbon capture, utilization, and storage
(CCUS). In this new concept, the CO 2 captured can be converted to valuable chemicals and materials. Some recent reports suggest the prospective utilization of CO 2
for synthetic applications in the fuel and chemical industries via reduction reactions, carboxylation, heterogeneously catalyzed hydrogenation, and photocatalytic
and electrocatalytic activations (Jiang et al. 2010; Wang et al. 2011; Kuhl et al.
2014). CO 2 can be employed for producing some value-added products, namely,
urea, methanol, salicylic acid, formic acid, formaldehyde, cyclic carbonates, ethylene carbonates, dimethyl carbonate, and copolymers as well as a few other fine
chemicals (Ganesh 2014; Alper and Yuksel Orhan 2017).
Although the concept of CCUS has multiple facets, yet it is challenging owing to
the limited literature available on this contemporary approach, which related to the
nascent knowledge on the consolidated CO 2 capture-utilization-storage process
operations, strengths and threats, techno-economics, and life cycle assessment. This
6 Conversion of Carbon Dioxide into Formaldehyde
Carbon capture and sequestration (CCS) refers to procedure for capturing and
storing CO 2 emitted from industrial processing of fossil fuels, power plants, and
product manufacturing sectors, thereby inhibiting its release into the atmosphere.
Nanda et al. (2016b) reviewed numerous routes existing for CO 2 capture from
industrial flue gases such as physicochemical, geological, and biological routes. The
physicochemical routes include absorption, membrane-based gas separation,
adsorption, and cryogenic distillation to separate and capture CO 2 in flue gas effluents (Yu et al. 2012). Moreover, the geological routes involve long-term storage of
CO 2 under the oceans and its mineralization to form carbonates in seawater (Khoo
and Tan 2006). The geological route is also related to the amendment of biochar
generated from thermochemical conversion of organic wastes into the soil to sequester the carbon for centuries as evidenced from the Amazonian terra preta (Nanda
et al. 2016a). On the other hand, the biological routes involve eco-friendly
approaches such as biological carbon fixation by algae and energy crops. The plants
utilize and fix CO 2 during photosynthesis to form carbohydrates (terrestrial plants)
and polysaccharides (algae). These polysaccharides and carbohydrates could be
potentially converted into fuels, chemicals, and hydrocarbons through thermochemical, i.e., pyrolysis, gasification, and liquefaction; biochemical, viz., fermentation
and methanation; and photocatalytic conversion approaches (Nanda et al. 2014).
Therefore, the biofuels are considered carbon-neutral as CO 2 emitted from biofuels
combustion is consumed by plants via photosynthesis (Nanda et al. 2013).
As mentioned earlier, through many physicochemical technologies such as
absorption and adsorption, CO 2 can be separated and captured from the industrial
emissions. However, the potential utilization of this captured CO 2 is highly imperative to account for sustainability. Since CO 2 is a major greenhouse gas, it is always
looked upon as an adversative component. The many versatile industrial utility of
CO 2 is rarely acknowledged in the literature. Realizing the perceptible carbon
sequestration projects worldwide and the massive amounts of CO 2 captured, its utilization for value-added products could attribute to a sustainable and circular economy. In simple words, the CO 2 captured from industrial flue gases can be the
potential raw material for commercial chemical and fuel industries (Jiang et al.
2010). This opens up the new concept of carbon capture, utilization, and storage
(CCUS). In this new concept, the CO 2 captured can be converted to valuable chemicals and materials. Some recent reports suggest the prospective utilization of CO 2
for synthetic applications in the fuel and chemical industries via reduction reactions, carboxylation, heterogeneously catalyzed hydrogenation, and photocatalytic
and electrocatalytic activations (Jiang et al. 2010; Wang et al. 2011; Kuhl et al.
2014). CO 2 can be employed for producing some value-added products, namely,
urea, methanol, salicylic acid, formic acid, formaldehyde, cyclic carbonates, ethylene carbonates, dimethyl carbonate, and copolymers as well as a few other fine
chemicals (Ganesh 2014; Alper and Yuksel Orhan 2017).
Although the concept of CCUS has multiple facets, yet it is challenging owing to
the limited literature available on this contemporary approach, which related to the
nascent knowledge on the consolidated CO 2 capture-utilization-storage process
operations, strengths and threats, techno-economics, and life cycle assessment. This
6 Conversion of Carbon Dioxide into Formaldehyde