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Titanate nanotubes (TiNT) were synthesized by hydrothermal method and used as support of rhodium nanoparticles. Results of X-Ray diffraction (XRD) and Raman spectroscopy of TiNT revealed its structure of Na 2 Ti 3 O 7 , while the results of Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and physisorption of N 2 confirmed the multilayer nanotubular morphology with external diameter of ∼ 12 nm, length > 100 nm and a BET surface area of 195 m 2 g À 1 . The TEM analysis of the rhodium supported sample (Rh/TiNT) showed evidence of small (∼ 1 nm) and highly dispersed rhodium particles. Results of X-Ray Photoelectron Spectroscopy (XPS) revealed a strong electronic interaction between TiNT and Rh sites. The catalytic activity of Rh/TiNT for the hydrogenation of CO 2 to formic acid at moderate temperature (∼ 40°C) and atmospheric pressure was demonstrated as evidenced by results of Mass Spectrometry (MS) and in-situ Diffuse Reflectance Infrared with Fourier Transform Spectroscopy (DRIFTS). The in-situ studies showed active surface species bonded to support sites and to rhodium sites. It is proposed that under H 2 atmosphere, Na + cations near to Rh particles promote the conversion of CO 2 via dissociated H, allowing the formation of formate species at low temperature. The formate species and the hydride rhodium complexes are considered reaction intermediates.[a] Prof.

One of the processes most used in biotechnology today for handling industrial liquid wastes is biological wastewater treatment. The efficiency and quality of its operation depends on the composition and activity of the microbial community that is present. The application of traditional and molecular techniques has provided a glimpse into the "black box" and has given information to improve the wastewater treatment process. However, bleach pulp and paper mill effluents require a better understanding of the active bacterial population. For the study of these microorganisms, molecular techniques have been used for more than 15 years. However, there has been a lack of knowledge of the physiological requirements and relations with the environment, which seems to be very difficult to obtain involving profile on the diversity. Nowadays, highthroughput sequencing technology is a promising method that makes it possible to identify the entire profile of microbial communities. In combination with fingerprint methods, this approach allows the identification and analysis of the whole biodiversity of microbial communities. In this review, several identification techniques will be discussed.

The pulp and paper mill process requires large amounts of water. Therefore, the need to reuse water through the application of coagulation-flocculation processes, which is effective in the removal of solids and colloidal particles, has risen. In such processes, zeta potential (ZP) provides important information about the efficiency of the reagents used. The purpose of this study was to develop individual and combined tests of reagents to study turbidity and COD reduction based on ZP in the process of wastewater internal treatment for recirculation in the pulp and paper process. Factorial models were developed to explain the behavior of ZP depending on the different coagulants/flocculants. The statistical analyses showed that ZP had a positive correlation with parameters related to removal (COD and turbidity). It was demonstrated that innovate use of lentil extract (Lens esculenta) applied with aluminum sulfate favored the treatment, consistent with a coagulation-flocculation mechanism. The optimum doses of lentil extract were able to reduce the requirements of aluminum sulfate by almost 29%, providing an alternative strategy for water reuse processes in the pulp and paper industry.

a Pulp and paper mills are a major source of pollution, generating huge amounts of intensely colored effluent that goes to the receiving end of a wastewater treatment plant. The biochemical oxygen demand test (BOD5) relies heavily on the microorganism metabolic capability added to the test as seeding material. The seeding material in the testing is obtained from sewage sampling or from commercial sources. Specific organic pollutants that are present in paper and pulp mill effluent can only be degraded by specific microbes; therefore, common sewage or synthetic seed may lead to erroneous BOD5 estimations. In this study, specific microbial species were selected to evaluate their degradation efficiency, both individually and in combination. The microorganisms selected in the formulated seed exhibit BOD5 in a reproducible and synergistic manner. The formulation of this specific microbial consortium can be used to develop bioremediation strategies.