by Carsten Unglaub  , Johannes Thiessen  and Andreas Jess

Received: 27 September 2022;  Published: 03 January 2023;  doi: 10.21926/cr.2301001

Fischer-Tropsch reactors operated in a steady state suffer from a low pore effectiveness factor and a high methane selectivity caused by internal mass transfer limitations due to the accumulation of long-chain hydrocarbons inside the catalyst pores. Therefore, an alternating process switching between Fischer-Tropsch synthesis (FTS) and drainage of the pores by hydrogenolysis is proposed. The periodical cracking of the accumulated waxes within the (partially) filled pores, realized by a switch from syngas (H2, CO) t [...]

by Otto V.M. Bueno  , Miguel A. San-Miguel  and Edison Z. da Silva

Received: 10 October 2022;  Published: 14 December 2022;  doi: 10.21926/cr.2204043

Linear atomic chain (LAC) gold nanowires (Au-NWs) containing oxygen impurities are materials that could be used as supports to stimulate chemical reactions. Its peculiar structural characteristics, such as abnormal Au-Au bonds, make it interesting to explore the chemical reactions of this material at a theoretical level. This work investigated the chemical reaction of ethanol supported on Au-NW containing two oxygen impurities. Using ab initio molecular dynamics simulations, it was shown that the presence of oxygen [...]

by Wei Wang  , Sa Bi  , Huanhuan Li  and Tiesheng Li

Received: 21 September 2022;  Published: 02 December 2022;  doi: 10.21926/cr.2204042

Fabrication, arrangement, and controllable composition of ordered organometallic films are critical for designing a highly active catalyst and investigating the catalytic mechanism. In this paper, an organometallic terpyridine Pd(II)/Ni(II) monolayer linked on the silicon substrate surface (denoted as Si-Tpy-Pd1/Ni1) was prepared and characterized using water contact angle, ultraviolet spectra, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron microscopy. Si-Tpy-Pd1/Ni1 exhibited high catalyt [...]

by Oreste Piccolo  , Elisabetta Parodi  and Antonella Petri

Received: 14 September 2022;  Published: 17 November 2022;  doi: 10.21926/cr.2204041

In this study, a PoC (Proof of Concept) of a possible biomass valorization of flax and camelina oilseed press cakes was presented. Biocatalyzed hydrolysis of residual oils and proteins extracted from these wastes was studied. The biotransformation of oils was performed using commercial immobilized lipases, including Amano PS, Amano AK, and Candida Antarctica Lipase B (CALB). Acylglycerols were partially or fully hydrolyzed using Amano PS and AK. Triglycerides were not hydrolyzed by CALB, which behaved differently. [...]

by Azra Shafi  and Qayyum Husain

Received: 06 August 2022;  Published: 17 November 2022;  doi: 10.21926/cr.2204040

Interpreting the relationship between the activity and structure of β-galactosidase is necessary to perceive the impact of the enzyme’s conformation on its catalysis. The current study thoroughly explains the effects of additives such as ethylenediaminetetraacetic acid (EDTA), sodium dodecyl sulfate (SDS), dithiothreitol (DTT), and urea on β-galactosidase activity and structure. β-Galactosidase activity was determined at various ionic strengths and temperatures as a function of time. Structural [...]

by Amit Ahlawat  , Tarun Kumar Dhiman  , Pratima R. Solanki  and Pawan S. Rana

Received: 24 July 2022;  Published: 03 November 2022;  doi: 10.21926/cr.2204039

Organic compounds are one of the most severe pollutants occurring in the environment. Hence, it is important to remove these compounds from the environment through remediation processes such as photocatalysis. The present study investigated the photocatalytic degradation of p-nitrophenol (NP) and phenol red (PR) using a cerium oxide-titanium oxide nanocomposite (CeO2-TiO2nc) under UV light. CeO2-TiO2nc was synthesized using the co-precipitation method. An X-ray diffraction (XRD) analysis confirmed the phase purity [...]

by Mateus Carvalho  , Ana Paula Oliveira  , Francieli Mayer  , Cesário Virgens  and Maria do Carmo Rangel

Received: 31 August 2022;  Published: 02 November 2022;  doi: 10.21926/cr.2204038

Catalytic pyrolysis is an attractive alternative for converting biomass into energy and chemicals to replace fossil sources. This has encouraged the search for efficient catalysts that can directly remove oxygenated products during pyrolysis, since they are the main problem in the processing and use of the products obtained. The catalytic and non-catalytic pyrolysis of medium density fiber (MDF) over beta zeolite-supported nickel (3 and 5%) was performed using the biomass/catalyst of 1.0/0.2 ratio. The thermokineti [...]

by Elvira A. Guseinova  and Samira R. Safarova

Received: 28 July 2022;  Published: 26 October 2022;  doi: 10.21926/cr.2204037

In this study, we found that adding catalytic cracking feedstock, vacuum gas oil, and naphthenic acids in the amount of 0.005–0.0075% vol. increased the liquid target fractions, i.e., gasoline and light gas oil. The decrease in the yield of hydrocarbon gas at a practically constant degree of conversion of the raw material indicated a small proportion of the reactions of re-cracking of the resulting products. This also indicated the resource-saving nature of the process, allowing a larger amount of gasoline fraction [...]

by Simona Bassoli  , Anett Schallmey  , Julie Oble  , Giovanni Poli  and Alexandre Pradal

Received: 22 July 2022;  Published: 26 October 2022;  doi: 10.21926/cr.2204036

A two-step protocol for the synthesis of aryl-3-hydroxypropanones, which were regarded as lignin degradation products, was proposed herein. This protocol provided a more rapid and easier access to aryl-3-hydroxypropanones, and aryl-3-hydroxypropanones were expected to be ideal platform molecules for the synthesis of more complex value-added targets.

by Manal Al-Eid  , Lianhui Ding  , Donya Sewdan  , Emad N. AL-Shafei  , Rasha Al-Ghamdi  , Abdulaziz Alqarawi  and Essa Al naimi

Received: 13 August 2022;  Published: 17 October 2022;  doi: 10.21926/cr.2204035

Parent ZSM-5 and Ga-modified ZSM-5 catalysts with different Si/Al ratios and particle sizes were prepared. The physicochemical properties of the prepared catalysts were investigated by performing X-ray powder diffraction analysis, BET surface area analysis, and NH3-TPD analysis. The performance of the aromatization reaction of the prepared catalysts was evaluated with 1-hexane as a model compound. The zeolite catalysts with a low SiO2/Al2O3 ratio possessed better activity than those with a high SiO2/Al2O3 ratio. Ga [...]