**Table 5.**

*MOFs and adsorption of organic dyes.*

*Adsorption Processes in the Removal of Organic Dyes from Wastewaters: Very Recent… DOI: http://dx.doi.org/10.5772/intechopen.94164*


ix. rhodamine B: WS2/WO3 (237) [52],


xiii. acid blue 92: nanoporous composites (556) [54].

## **3. Conclusions**

During the first quarter of 2020 year, an important number of dye adsorption procedures have been proposed in a series of published papers, all of them, claiming successful dye removal. However, in the opinion of the authors of the present review some criticism to the papers must be accounted for:



#### **Table 6.**

*Difference in organic dyes adsorption capacity of various adsorbents.*

It is needed to mention here, that in Refs. [63, 64] a heavy scientific fault was detected: the authors of the manuscripts investigated, besides the adsorption of organic dyes, the adsorption of Cr6+, written as such, when this element in the VI oxidation state, never exists as a cation in aqueous solutions. This fault also is responsibility of the corresponding reviewers and of the Editors.

In practical terms, the real bottlenecks in the usefulness of these adsorbents are:


### **Acknowledgements**

To the CSIC Spanish Agency for support. Authors also acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

*Adsorption Processes in the Removal of Organic Dyes from Wastewaters: Very Recent… DOI: http://dx.doi.org/10.5772/intechopen.94164*
