Advances in Rosin-Based Chemicals: The Latest Recipes, Applications and Future Trends

A comprehensive review of the publications about rosin-based chemicals has been compiled. Rosin, or colophony, is a natural, abundant, cheap and non-toxic raw material which can be easily modified to obtain numerous useful products, which makes it an excellent subject of innovative research, attracting growing interest in recent years. The last extensive review in this research area was published in 2008, so the current article contains the most promising, repeatable achievements in synthesis of rosin-derived chemicals, published in scientific literature from 2008 to 2018. The first part of the review includes low/medium molecule weight compounds: Especially intermediates, resins, monomers, curing agents, surfactants, medications and biocides. The second part is about macromolecules: mainly elastomers, polymers for biomedical applications, coatings, adhesives, surfactants, sorbents, organosilicons and polysaccharides. In conclusion, a critical evaluation of the publications in terms of data completeness has been carried out with an indication of the most promising directions of rosin-based chemicals development.

Synthesis, characterization and activity performance of nickel-loaded spent FCC catalyst for pine gum hydrogenation

A Ni-based catalyst supported over a spent fluid catalytic cracking (FCC) catalyst was prepared by a wet impregnation method. The catalytic characteristic was investigated in pine gum hydrogenation. Optimum conditions for catalyst preparation were obtained as: 15% Ni loading, 723 K calcination temperature, and 723 K reduction temperature for 2.5 h. The characterization results indicate that the specific surface area of the spent catalyst increased from 65.70 m² g⁻¹ to 67.78 m² g⁻¹ after calcination. The H₂-TPR profile of the spent FCC catalyst exhibited two reduction peaks at 1123 °C and 670 °C. The TG curves showed that the second and third steps occur at 440 K and 550 K, respectively, having a total weight loss of 16%. The NiO grains possess rhombus particles on the surface or between the layers of the supported NiO catalyst. After activation in H₂ flow, the metallic Ni loads on the support with no covalent bond between them. The NH₃-TPD results indicated that the spent FCC catalyst held an obvious distribution of weakly acidic sites, and the acid sites became stronger after loading the catalyst with Ni. The hydrogenation products of pine gum were identified by GC-MS and a reaction mechanism was proposed. This study demonstrated its cost-effectiveness, environment-friendly nature and that the utilization of a spent FCC catalyst can be effectively applied as an alternative approach to pine gum hydrogenation on an industrial level.

A Ni-based catalyst supported over a spent fluid catalytic cracking (FCC) catalyst was prepared by a wet impregnation method.

Catalytic methyl esterification of colophony over ZnO/SFCCR with subcritical CO2: catalytic performance, reaction pathway and kinetics

A heterogeneous catalyst (ZnO/SFCCR) composed of ZnO supported on spent fluid cracking catalyst by wet impregnation was synthesized and applied to the esterification of colophony acids with methanol under subcritical CO₂ conditions. The catalyst was characterized by SEM-EDS, BET, ICP, FTIR, XRD and Py-IR. An experimental set-up involving a new injection technique was designed to promote the heterogeneous methyl esterification, and the subcritical CO₂ played a role in auxiliary acid catalysis (a pH range of 3.54-3.91), increasing the lifespan of ZnO/SFCCR, reducing the viscosity of the system to promote gas-liquid mass transfer. A maximum conversion rate of 97.01% was obtained in a relatively short time of 5 h. Kinetic experiments were performed from 190 to 220°C using a special high-temperature sampling device and analysing aliquots with high-performance liquid chromatography. A new reaction pathway, involving methyl abietate, methyl dehydroabietate, methyl neoabietate and methyl palustrate along with other kinds of colophony acids, was developed. The kinetic parameters were obtained using the Levenberg-Marquardt nonlinear least-squares method, and the activation energies for the isomerizations of neoabietic and palustric acids and for the methyl esterification of neoabietic, abietic, palustric and dehydroabietic acids were found to be 107.09, 113.95, 68.99, 49.85, 75.43 and 59.20 kJ mol^-1, respectively. The results from the kinetic model were in good agreement with experimental values.

A Ni-based catalyst with polyvinyl pyrrolidone as a dispersant supported in a pretreated fluid catalytic cracking catalyst residue for C9 petroleum resin (C9 PR) hydrogenation

A Ni-based catalyst (Ni-PVP/PFC3R) with polyvinyl pyrrolidone (PVP) as a dispersant supported in a pretreated fluid catalytic cracking catalyst residue (PFC3R) was synthesized and applied to C9 petroleum resin (C9 PR) hydrogenation. For comparison, a Ni catalyst without PVP (Ni/PFC3R) was prepared in the same way. Ni-PVP/PFC3R exhibited higher activity and better stability. The catalysts were characterized by X-ray diffraction, scanning electron microscope, H₂-temperature programmed reduction/temperature programmed desorption, Fourier transform infrared spectroscopy and the Brunauer-Emmett-Teller method. The catalysts had a smaller crystallite size and stronger interactions between the Ni species and the PFC3R support in the presence of PVP. The effects of nickel loading, H₂ pressure, temperature and reaction time for C9 PR hydrogenation over Ni-PVP/PFC3R were investigated. The bromine number was reduced to 1.25 under the following conditions: nickel content of 12 wt%, PVP amount of 1.5 wt%, temperature of 270°C, H₂ pressure of 8 MPa and reaction time of 240 min.