**4. Conclusions**

*Biotechnological Applications of Biomass*

*FTIR of lignin and lignosulfonate bagasse.*

*Sugarcane becomes lignosulfonate [35].*

wavelengths close to the standard spectrum wavelength values. Lignin from bagasse can be completely synthesized into sodium lignosulfonate surfactant completely with lignosulfonate components consisting of alkene, sulfonate, carboxylate,

**Indicator Component Wavelength (cm−1)** Lignin Phenolic O-H 3400

Lignosulfonates Alkene C═C 1635.34

Aliphatic and aromatic ▬CH▬ 2910

Ketone C═O 1450 Arena ▬C═C — Amine C▬N 1100 Alkyl C▬H 650

Sulfate S═O 1384.64 Carboxylic acids C═O 1114.65 Ester S-OR 462.832

Furthermore, from the results of the NMR test, the components form the lignosulfonate. In the HMQC data, it can be seen that the proton nuclei are directly correlated with carbon-13 (13C) or have one bond (1JC, H) so that their own pairs can be known with certainty. The broad singlet signal on the δ H 6.64 ppm chemical shift (2H, bs, H−3, and H-5) correlates directly with carbon at δ C 102.2 ppm (C-3 and C-5). In addition, the HMQC spectrum also indicates the presence of methylene protons bound to C-9, methane bound to oxygen, and sulfate bound to C-8 and C-7, respectively.

From the HMBC spectrum, it can be seen that there is a correlation between protons and carbon with a distance of two bonds (2 J) to three bonds (3 J), which can be seen in **Figure 3**. From the HMBC data, it can be seen that there is a correlation between H-3 and H-5 with C-5/C-3, C-1, and C-7; H-7 correlates with C-8 and H-9 correlates with C-8 and C-7. These data support the existence of phenyl propanoid compounds as the basis for lignosulfonates [38]. The correlation between HMQC and HMBC can be seen in **Figure 11**. With the results that look like this, it shows that the isolation process of lignin from bagasse has been successful. Likewise, the

sulfonation of lignin to lignosulfonate has also been successful.

**72**

and ester.

**Figure 10.**

**Table 4.**

Based on the results of the lignin sulfonation process on lignin sulfonation optimization, several conclusions can be drawn, namely:


*Biotechnological Applications of Biomass*
