**3. Reactions for manufacturing industrial chemicals**

Production of industrial chemicals utilizes a variety of reactions to convert the raw materials to the desired products. The following is a list of the reactions involved in the manufacture of the top 100 industrial chemicals and their chemical classification.




**Table 2** lists the chemical reactions, yield, and the calculated atom economy, used in the analysis, based on the reported reaction yields [4]. The following equation was





#### **Table 2.**

*Industrial chemical reactions, commercial yield and atom economy.*

used to calculate the carbon economy from the reported data and a balanced reaction pathway:

%Carbon economy ¼ ½ � ð Þ Unit weight of product *=*Unit weight of raw materialð Þ*s*

�½ � Molecular Weight of raw materialð Þ*s =*Molecular Weight of product

�½Moles of carbon in product*=*Moles of carbon in raw materials� � 100*:*

(1)

### **4. Reaction pathways from biomass to industrial chemicals**

The reaction pathways for the top industrial chemicals, as listed in the previous section, were combined with the biomass conversion reactions to maximize the overall carbon economy. This yielded biomass conversion reaction pathways to the major industrial chemicals, and these conversion paths with the maximum carbon economy are listed in **Table 3**.

Although several biomass sources were used in the analysis, only beechwood, pine sawdust, sunflower residue, rape residue, sewage sludge, alaskan spruce, tropical luan, and rice husk were selected to maximize the overall carbon economy, with beechwood and pine sawdust being mostly used to generate the chemical intermediate. Sewage sludge was used to generate benzene as an intermediate chemical, which could then be converted to other aromatic compounds. The carbon economy for sewage sludge conversion to aromatics was less than 10%, which may render these chemical paths uneconomical.

The following examples from **Table 3** illustrate the biomass conversion reactions which had the highest atom economy for two industrial chemicals.

Butadiene can be produced from biomass using the following steps:


**Figure 1** shows a schematic of the reaction pathway to convert beech wood to butadiene.





#### **Table 3.**

*Chemical pathways for converting biomass to industrial chemicals with the overall carbon economy.*

#### **Figure 1.**

*Reaction path for manufacturing butadiene from beech wood.*

#### **Figure 2.**

*Reaction path for manufacturing Di ethylene glycol from pine sawdust.*

Another example of a reaction pathway is the conversion of pine sawdust to diethylene glycol, and this reaction pathway with their respective atom economies is shown in **Figure 2**. This pathway has the highest carbon economy for manufacturing diethylene glycol from a biomass source.
