## 5 Conclusions  
The present study holistically approached the global LBAs research applied to cement-based composites. Lignin valorization has gained popularity since 2011 and it is expected that more near-future studies will be published in this area. The scientometric analysis revealed that China was the most collaborative country in the LBAs research, although the USA and Canada also collaborated significantly. In addition, the LBAs research encompasses journals with different categories (e.g., agricultural and biological sciences and materials science), demonstrating the multidisciplinary of the subject.  
The in-depth analysis of the literature data indicated that there is still room for further research on LBAs. In summary, the qualitative discussion revealed that:  
* Most research has focused on developing LBAs using modified and unmodified Kraft lignins. The use of other technical lignins must be better understood to expand and diversify the LBAs research;
* The use of lignins obtained in biorefinery processes and residual black liquors is a viable alternative to consolidate emerging economies in LBAs research. In addition, incorporating LBAs jointly with residual mineral admixtures is an important step toward more sustainable practices in the construction industry;
* LBAs can be classified as plasticizers, superplasticizers, air-entraining agents, and set retarders. The LBAs developed so far were applied mainly in ordinary cement-based composites. In this sense, there is a lack of studies focusing on the incorporation of LBAs in special concrete and mortar (e.g., UHPC and lightweight concrete);
* Most research focused on the production processes and chemical characterization of LBAs. However, the evaluation of the mechanical and physical properties of LBA-containing composites needs more attention in further research since unwanted side effects of LBAs may affect the matrix-hardened properties.  
It stands out that the authors dealt with the limitations of the database and the software used. To conclude, it is expected that the innovation of this study will contribute to the understanding of lignin-based admixtures and the discussion on the development of more sustainable cement-based composites.  
Conceptualization, V.R.C.; methodology, V.R.C. and L.C.B.C.; validation, V.R.C., L.C.B.C., B.E.L.B. and R.A.F.P.; formal analysis, V.R.C.; investigation, V.R.C.; resources, V.R.C., L.C.B.C., B.E.L.B. and R.A.F.P.; writing--original draft preparation, V.R.C.; writing--review and editing, V.R.C., L.C.B.C., B.E.L.B. and R.A.F.P.; supervision, B.E.L.B. and R.A.F.P.; project administration, R.A.F.P.; funding acquisition, R.A.F.P. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This work was supported by the Coordination for the Improvement of Higher Education Personnel under research project no. 88887.5/575/14/2020-00. In addition, the article processing charge was funded by the Federal University of Ouro Preto and the Coordination for the Improvement of Higher Education Personnel through the \"EDITAL PROPPI/UFOP N\" 03/2023\".  
**Institutional Review Board Statement:** Not applicable.  
**Data Availability Statement:** The data used in this research have been properly cited and reported in the main text.  
**Acknowledgments:** We gratefully acknowledge the Federal University of Ouro Preto and the agencies CAPES, CNPq, and FAPEMIG for providing financial support. We are also grateful for the infrastructure and collaboration of the Research Group on Solid Waste-RECIClos/CNPq and its partners.  
**Conflicts of Interest:** The authors declare no conflict of interest.