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This study investigated the immobilization of recombinant lipase onto modified Nickel foam to enhance enzyme lifespan and reusability in palm oil hydrolysis. Nickel foam, with its high porosity and extensive surface area, provides optimal support for enzyme catalysis, facilitating enhanced substrate-enzyme interaction. Employing Nickel foam as an immobilization matrix for lipase within a Rotating Bed Reactor (RBR) offers a novel method to optimize fatty acid production. Physicochemical analysis confirmed a 97.45 % immobilization yield and 74.93 % retention of its initial activity, demonstrating efficient immobilization and stability. The turnover frequency (TOF) of the immobilized lipase increased with rotation speed, achieving an optimal 55.38 % fatty acid conversion at 600 rpm over 9 hours. Compared to the free enzyme, the immobilized form showed notable thermal stability, retaining 85.40 % activity after two days at 60 °C, and maintained performance over six reuse cycles. Furthermore, the immobilized lipase required 3.82 times less enzyme to achieve the same amount of product as the free enzyme. These findings highlight the potential of Nickel foam as an effective support for His-tagged enzymes, significantly enhancing durability and reusability in palm oil hydrolysis, thus supporting more efficient fatty acid production.

This paper investigates separate pyrolysis of corn stalk(CS)and polypropylene(PP)and co-pyrolysis of CS and PP over Zn-Al co-modified MCM-41 to produce aromatics, and the product distribution of catalytic co-pyrolysis of CS and PP was studied based on a rotating bed reactor. The results showed that the product contents and composition were significantly influenced in the presence of catalysts. Zn and Al showed a certain synergistic effect, under the catalysis of MCM-41 co-modified by Zn with mass fraction of 1% and Al with mass fraction of 3%, and the maximum proportions of aromatics(24.31%)and the minimum production of oxygenated compounds(12.37%)were obtained. In the experiment of catalytic co-pyrolysis of CS and PP in rotating bed, with the increase of pyrolysis temperature(500—800 ℃), the yield of bio-oil decreased gradually. The decrease of olefins and oxygenates in bio-oil significantly increased the content of aromatic hydrocarbons. With the increase of catalyst dosage(1:0—1:10), the yield of bio-oil reduced gradually. The contents of aromatic hydrocarbons in bio-oil increased obviously, while the contents of olefins and oxygenates decreased. With the increase of rotating speed(0—20 r/min), the yield of bio-oil first decreased and then increased. The extreme values of aromatics, olefins, and oxygenates in bio-oil were all obtained at 15 r/min. [ABSTRACT FROM AUTHOR]

Ascorbyl palmitate, an ascorbic acid ester, is an important amphipathic antioxidant that has several applications in foods, pharmaceuticals, and cosmetics. The enzymatic synthesis of ascorbyl palmitate is very attractive, but few efforts have been made to address its process scale-up and implementation. This study aimed at evaluating the enzymatic synthesis of ascorbyl palmitate in a rotating basket reactor operated in sequential batches. Different commercial immobilized lipases were tested, and the most suitable reaction conditions were established. Among those lipases studied were Amano Lipase PS, Lipozyme® TL IM, Lipozyme® Novo 40086, Lipozyme® RM IM and Lipozyme® 435. Initially, the enzymes were screened based on previously defined synthesis conditions, showing clear differences in behavior. Lipozyme® 435 proved to be the best catalyst, reaching the highest values of initial reaction rate and yield. Therefore, it was selected for the following studies. Among the solvents assayed, 2-methyl-2-butanol and acetone showed the highest yields, but the operational stability of the catalyst was better in 2-methyl-2-butanol. The tests in a basket reactor showed great potential for large-scale application. Yields remained over 80% after four sequential batches, and the basket allowed for easy catalyst recycling. The results obtained in basket reactor are certainly a contribution to the enzymatic synthesis of ascorbyl palmitate as a competitive alternative to chemical synthesis. This may inspire future cost-effectiveness studies of the process to assess its potential as a viable alternative to be implemented. [ABSTRACT FROM AUTHOR]

Tall oil fatty acids are a second-generation bio-based feedstock finding application in the synthesis of polyurethane materials. The study reported tall oil fatty acids and their methyl esters epoxidation in a rotating packed bed reactor. The chemical structure of the synthesized epoxidized tall oil fatty acids and epoxidized tall oil fatty acids methyl ester were studied by Fourier-transform infrared spectroscopy. Average molecular weight and dispersity were determined from gel permeation chromatography data. The feasibility of multiple uses of the Amberlite® IRC120 H ion exchange resin as a catalyst was investigated. Gel permeation chromatography chromatograms of epoxidized tall oil fatty acids clearly demonstrated the formation of oligomers during the epoxidation reaction. The results showed that methylation of tall oil fatty acids allows obtaining an epoxidized product with higher relative conversion to oxirane and much smaller viscosity than neat tall oil fatty acids. Epoxidation in a rotating packed bed reactor simplified the process of separating the catalyst from the reaction mixture. The Amberlite® IRC120 H catalyst exhibited good stability in the tall oil fatty acids epoxidation reaction. [ABSTRACT FROM AUTHOR]

• A novel design of basket reactor with stationary bed (StatBioChem) was developed. • StatBioChem reactor - a novel design for heterogeneous biocatalysis. • StatBioChem was compared to a commercial rotating bed reactor (SpinChem®). • Process efficiency (STY) was two times higher for Statbiochem than for SpinChem®. • Simple construction and design of Statbiochem reactor. Effectiveness of catalytic processes using heterogeneous biocatalysts depends not only on the activity of the enzyme, but also on the efficiency of the used reactor. In this paper, we present a novel design of a basket reactor with a stationary catalyst bed (StatBioChem). The developed design was compared to a commercially available rotating bed reactor (SpinChem®). The biocatalysts used were invertase and acyltransferase from Mycobacterium smegmatis (MsAcT) immobilised on macroporous silica supports. The obtained values of initial reaction rate, both in the reaction of saccharose hydrolysis and 2,2-dimethyl-1,3-propanediol (NPG) transesterification, were twice higher for the StatBioChem reactor. A similar relationship was also observed regarding the process efficiency expressed as STY. [Display omitted] [ABSTRACT FROM AUTHOR]

An oxygen-free pyrolysis technique employing Shenwu rotating bed reactor with regenerative radiant tube as high temperature heat source was investigated to recycle municipal solid waste. To obtain the optimum condition of this technique, the effects of heating source temperature, arrangement and material thickness on … were discussed, and the compositions and yields of products were studied experimentally. A three-dimensional transient mathematical model characterized with simultaneous fluid flow, heat and mass transfer was established to describe the pyrolysis process in a rotating bed reactor. The model was calibrated based on experimental data. Results show that this new technique has good commercial due to the possibility of avoiding the tar congestion problem effectively and obtaining clean gas with high caloricity. [ABSTRACT FROM AUTHOR]

In this work the activity of ruthenium decorated carbon foam (Ru/CF) catalyst was studied in three phase hydrogenation reaction of d-xylose to d-xylitol. The developed catalyst was characterized by using scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, inductively coupled plasma optical emission spectrometry and nitrogen adsorption-desorption measurement. Kinetic measurements were carried out in a laboratory scale pressurized reactor (Parr) assisted by SpinChem rotating bed reactor (SRBR), at pre-defined conditions (40-60 bar H and 100-120 °C). The study on the influence of reaction conditions showed that the conversion rate and selectivity of hydrogenation reaction of d-xylose was significantly affected by temperature. These results have been proved by a competitive kinetics model which was found to describe the behavior of the novel system (Ru/CF catalyst used together with the SRBR) very well. Besides, it was revealed that the catalytic activity as well as the stability of our Ru/CF-SRBR is comparable with the commercial ruthenium decorated carbon catalyst (Ru/AC) under identical reaction conditions. Moreover, all steps from catalyst preparation and catalyst recycling as well as catalytic testing can be performed in an easy, fast and elegant manner without any loss of materials. Briefly, the developed Ru/CF catalyst used together with the SRBR could be used an excellent alternative for the conventional Raney nickel catalyst in a slurry batch reactor and offers an attractive concept with obvious industrial applicability. [ABSTRACT FROM AUTHOR]

This study proposed a new pyrolysis technique for municipal solid waste under anaerobic environment with regenerative radiant tube as the high-temperature heat source within a rotating bed reactor. To obtain the optimum condition of this technique, the effect of heating source temperature, arrangement and bed thickness on the distribution, composition and yield of products was experimentally studied. A three-dimensional transient mathematical model was established to describe the pyrolysis process characterized with simultaneous fluid flow, heat and mass transfer in a rotating bed reactor. The simulation model parameters were also modified based on experimental data. Results showed that this new technique has commercial viability due to the possibility to effectively avoid the problem of tar congestion and obtain high caloricity clean gas. [ABSTRACT FROM AUTHOR]

Highlights: [•] A mathematical model for the rotating CLC reactor has been developed. [•] The model reflects the gas distribution in the reactor during CLC operation. [•] Radial dispersion in the rotating bed is the main cause for internal gas mixing. [•] The model can be used to optimize the reactor design and particle characteristics. [ABSTRACT FROM AUTHOR]

Production of specialty chemicals increasingly makes use of the enzyme catalysts in organic solvents, and Novozym 435 (N435) is among most often applied. However, its polymeric skeleton is unstable in many solvents. In this context we report the results of a more systematic study of the biocatalysts, fabricated using highly porous siliceous pellets/enzyme carriers (MH, 4 cm3 g−1 total pore volume, 310 m2 g−1 surface area), grafted with octyl (-O), amino (-A) and octyl and amino (-OA) groups, to attach the enzyme - CALB lipase. The catalysts were deployed in a rotating bed reactor (RBR) and tested in hydrolysis of p -nitrophenyl acetate, and esterification of levulinic acid. Performance of the system was compared with the same RBR filled with N435. N435 appeared the most active in both reactions, when activity was related to bulk mass of the catalysts, mainly owing to very large enzyme load. But its pore structure degraded in many typical solvents already after 24 h of soaking, whereas no significant change in MH-O and MH-OA activity was detected. Irrespective of the solvent and reaction, the highest specific activity of the enzyme featured MH-O. However, a significant enzyme leaching from MH-O observed in a hydrolytic reaction, in stark contrast to MH-OA which came second in specific activity, point to MH-OA as the catalyst of choice for hydrolytic reactions. In esterification reaction the MH-O lipase was not only most active but it was also quite stable. Therefore, MH-O appears the most suitable production system for the reactions carried out in organic solvents. Image 1 • Structured silica beads with attached enzymes give highly active and stable catalysts. • Lipase on octyl group grafted silica is more active than in Novozym 435. • CALB on octyl/amino-silica is biocatalyst of choice for hydrolytic reactions. • CALB on octyl grafted silica is biocatalyst of choice for esterification reactions. • RBR-packed structured biocatalysts offer high yield production of specialty chemicals. [ABSTRACT FROM AUTHOR]