# Additive Manufacturing and Chemical Engineering: Looking for Synergies from a Bibliometric Study
## 5 Conclusions
Bioinks and biomaterial inks, which may include cells and biologically active components, are employed for the production of scaffolds and other structures. Hydrogels are the most commonly utilized materials in these inks due to their capacity to mimic the extracellular matrix of native tissues. However, composite hydrogels, which combine polymers with inorganic or organic nanof fillers, are becoming increasingly popular due to their capacity to enhance the structural and functional characteristics of bioinks. Additive manufacturing has enabled the creation of implants with intricate and bespoke internal geometries and structures. Moreover, bio-printing has demonstrated considerable promise in the context of organ transplantation, with notable advancement in the fabrication of living cellular structures. Additionally, bioprinting has demonstrated utility in drug discovery, enabling the fabrication of in vitro models of physiologically relevant human organs. However, comprehensive validations and standardizations are essential to ascertain the potential efficacy of this approach. Recent developments in chemical engineering are closely associated with the concept of process intensification, and additive manufacturing has the potential to make significant contributions to this field. For example, additive manufacturing enables the fabrication of heat exchangers with intricate geometries, thereby optimizing the area-volume ratio and enhancing the efficiency of heat transfer. However, the use of these heat exchangers may present certain challenges, including surface roughness, resolution, economic costs, and post-processing difficulties. Additionally, catalysts and adsorbents can benefit from the high area-volume ratio that additive manufacturing provides. The design of monolithic structures offers significant advantages over conventional configurations. Additive manufacturing appears to be a promising method for producing these materials, as it allows for a high degree of design freedom and the ability to adjust manufacturing parameters to obtain elements with high mechanical properties. Nevertheless, several challenges remain, including the need to achieve a balance between key design parameters and the necessity to enhance manufacturing technologies. The utilization of microreactors and miniaturized devices represents a further significant application of additive manufacturing within the domain of chemical engineering. This compact equipment facilitates efficient mass and heat transfer, offering several advantages over traditional large-scale operations. Additive manufacturing can surmount the challenges associated with economic costs and offers notable flexibility for the agile production of any required geometry. Nevertheless, several challenges remain to be addressed, including the multi-level connection in complex microreactors. The capacity of additive manufacturing to manage micro- and nanoscale resolutions has facilitated the production of separation membranes with applications spanning wastewater treatment and gas purification. Indeed, additive manufacturing has been demonstrated to be an effective solution for the production of membranes with high selectivity and permeability, in a manner that is both efficient and environmentally friendly. However, it should be noted that the membranes produced using additive manufacturing may face the same challenges as traditional membranes, such as fouling. Additive manufacturing will encounter challenges and opportunities in a number of areas that have yet to be fully integrated and that require further attention. Among these areas, the sustainability of additive manufacturing must be mentioned. Some chemical engineering tools, such as life cycle assessment and process and system optimization, can play a critical role in this regard. Life cycle assessment is a fundamental tool for evaluating the sustainability of a process.