Conversion of Glycerol to Value Added Products in a Semi-Continuous Batch Reactor Using Noble Metals Supported on ZSM-11 Zeolite

Au, Pt, and Pd supported on ZSM-11 microporous zeolite were investigated as catalysts for glycerol (GLY) oxidation towards higher value added products. ZSM-11 was synthesized by hydrothermal treatment. Subsequently, ion exchange with NH4Cl was performed to recover acidic sites and then, Au, Pt, and Pd were incorporated onto this material by wet impregnation procedure. After thermal treatment of desorption and calcination, the corresponding Au, Pt, and Pd-ZSM-11 catalysts were obtained. These materials were characterized by different techniques, such as XRD, ICP, TEM- XEDS, and XPS, and were evaluated in the glycerol oxidation reaction by using alkaline medium and molecular oxygen as oxidizing agent. The higher conversion of GLY (66.5 mol.%) was reached for the Pt–ZSM-11 catalyst with moderate selectivity towards lactic acid (LA), while the bimetallic Au-Pt-ZSM-11 catalyst offered high selectivity to LA at moderate GLY conversion. Optimization of the main reaction parameters (i.e., temperature, reaction time and NaOH/GLY ratio) was carried out to maximize the selectivity towards the LA desired product. Thus, LA selectivity values close to 55% at GLY conversion >65% can be reached by using Pt-ZSM-11 as a catalyst under mild reaction conditions.

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Catalytic Sulfone Upgrading Reaction with Alcohols via Ru(II)

10.26434/chemrxiv.11466972.v1 ◽

2019 ◽

Author(s):

Tomas Vojkovsky ◽

Shubham Deolka ◽

Saiyyna P. Stepanova ◽

Michael C. Roy ◽

Eugene Khaskin

Keyword(s):

Functional Groups ◽

Secondary Alcohol ◽

Value Added ◽

Catalytic Dehydrogenation ◽

Reaction Conditions ◽

Stoichiometric Amount ◽

Reaction Proceeds ◽

One Step ◽

Value Added Products

<a>Sulfones and sulfonamides with an α-CH bond can be easily alkylated by aliphatic alcohols to add the carbon skeleton of the alcohol via a one-step, Ru(II) catalyzed redox neutral reaction. The reaction requires a sub-stoichiometric amount of base and produces only water as a byproduct. A number of pharmaceutically relevant functional groups such as piperidine, morpholine, etc. are well tolerated under the reaction conditions to give higher value-added products in one step from widely available substrates. The reaction proceeds through a sulfone carbanion addition to an in-situ generated aldehyde formed via catalytic dehydrogenation and subsequent catalyst mediated replacement of the secondary alcohol by hydrogen.</a>

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Development of ‘Lignin-First’ Approaches for the Valorization of Lignocellulosic Biomass

Molecules ◽

10.3390/molecules25122815 ◽

2020 ◽

Vol 25 (12) ◽

pp. 2815 ◽

Cited By ~ 2

Author(s):

Tamás I. Korányi ◽

Bálint Fridrich ◽

Antonio Pineda ◽

Katalin Barta

Keyword(s):

Lignocellulosic Biomass ◽

Structural Modification ◽

Complex Structure ◽

Value Added ◽

Original Structure ◽

Reaction Conditions ◽

The Past ◽

Pulp Paper ◽

New Strategy ◽

Value Added Products

Currently, valorization of lignocellulosic biomass almost exclusively focuses on the production of pulp, paper, and bioethanol from its holocellulose constituent, while the remaining lignin part that comprises the highest carbon content, is burned and treated as waste. Lignin has a complex structure built up from propylphenolic subunits; therefore, its valorization to value-added products (aromatics, phenolics, biogasoline, etc.) is highly desirable. However, during the pulping processes, the original structure of native lignin changes to technical lignin. Due to this extensive structural modification, involving the cleavage of the β-O-4 moieties and the formation of recalcitrant C-C bonds, its catalytic depolymerization requires harsh reaction conditions. In order to apply mild conditions and to gain fewer and uniform products, a new strategy has emerged in the past few years, named ‘lignin-first’ or ‘reductive catalytic fractionation’ (RCF). This signifies lignin disassembly prior to carbohydrate valorization. The aim of the present work is to follow historically, year-by-year, the development of ‘lignin-first’ approach. A compact summary of reached achievements, future perspectives and remaining challenges is also given at the end of the review.

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Recent Progress in Solar-Induced Direct Biomass-to-Electricity Hybrid Fuel Cell Using Microalgae as Feedstocks

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.638971 ◽

2021 ◽

Vol 9 ◽

Author(s):

Kun-Tao Peng ◽

Xiang Wang ◽

Gong Peng ◽

Lin Yu ◽

Hong-Ye Li

Keyword(s):

Fuel Cell ◽

Noble Metals ◽

Recent Progress ◽

High Efficiency ◽

Value Added ◽

Phosphomolybdic Acid ◽

Low Noise ◽

Stress Regulation ◽

Biodiesel Feedstocks ◽

Value Added Products

Microalgae, as potential biodiesel feedstocks, have been widely reported to accumulate oil via genetic engineering techniques, or environmental stress regulation. Recently, the utilization of fuel cell technology to convert biomass into electricity has attracted much more attention due to its high efficiency, low pollution, low noise by microalgae as feedstocks. Normally, platinum and analogous noble metals as catalysts have been already demonstrated although they still exist lots of shortcomings. This mini review presents an overview of various fuel cell technologies with phosphomolybdic acid as catalysts for sustainable energy by using microalgae. Trends from literatures demonstrate that algal-based fuel cells could efficiently generate electricity, and concurrently produce high value-added products. This critical review can provide guiding suggestions for future study of algal-based energy conversion by fuel cell techniques.

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Catalytic Sulfone Upgrading Reaction with Alcohols via Ru(II)

10.26434/chemrxiv.11466972 ◽

2019 ◽

Author(s):

Tomas Vojkovsky ◽

Shubham Deolka ◽

Saiyyna P. Stepanova ◽

Michael C. Roy ◽

Eugene Khaskin

Keyword(s):

Functional Groups ◽

Secondary Alcohol ◽

Value Added ◽

Catalytic Dehydrogenation ◽

Reaction Conditions ◽

Stoichiometric Amount ◽

Reaction Proceeds ◽

One Step ◽

Value Added Products

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Synthesis and Characterization of SiO2Nanoparticles and Their Efficacy in Chemical Mechanical Polishing Steel Substrate

Advances in Materials Science and Engineering ◽

10.1155/2014/691967 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 11

Author(s):

M. J. Kao ◽

F. C. Hsu ◽

D. X. Peng

Keyword(s):

Chemical Mechanical Polishing ◽

High Selectivity ◽

Steel Substrate ◽

Sol Gel ◽

Aerospace Industry ◽

Value Added ◽

Mechanical Polishing ◽

Reaction Conditions ◽

Abrasive Size

Chemical mechanical polishing (CMP) technology is extensively used in the global planarization of highly value-added and large components in the aerospace industry. A nanopowder of SiO2was prepared by the sol-gel method and was compounded into polishing slurry for the CMP of steel substrate. The size of the SiO2abrasives was controlled by varying the sol-gel reaction conditions. The polishing efficacy of nano-SiO2was studied, and the CMP mechanism with nanosized abrasives was further investigated. The proposed methods can produce SiO2abrasives whose size can be controlled by varying the sol-gel reaction conditions. The size of the SiO2abrasives was controlled in the range from 58 to 684 nm. The roughness of the steel substrate strongly depends on the size of the abrasive, and the surface roughness decreases as the abrasive size declines. A super-smooth surface with a roughness of 8.4 nm is obtained with nanosized SiO2. Ideal CMP slurry can be used to produce material surfaces with low roughness, excellent global planarization, high selectivity, an excellent finish, and a low-defected rate.

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Chemo- and Regioselective Hydroformylation of Alkenes with CO2/H2 over a Bifunctional Catalyst

10.21203/rs.3.rs-85641/v1 ◽

2020 ◽

Author(s):

Kai HUA ◽

Fang Liu ◽

Yin Wei ◽

Long Shao ◽

Chao Deng ◽

...

Keyword(s):

Value Added ◽

Building Blocks ◽

Bifunctional Catalyst ◽

Basic Site ◽

Bidentate Ligands ◽

Mechanistic Studies ◽

Reaction Conditions ◽

Fast Release ◽

Value Added Products

Abstract Combining CO2 and H2 to prepare building blocks for high-value-added products is an attractive yet challenging approach. A general and selective rhodium-catalyzed hydroformylation of alkenes using CO2/H2 as a syngas surrogate is described here. With this protocol, the desired aldehydes can be obtained in up to 97% yield and 93/7 regioselectivity under mild reaction conditions (25 bar, 80 ºC). Key-to-success is the use of bifunctional Rh/PTA catalyst (PTA: 1,3,5-triaza-7-phosphaadamantane), which facilitates both CO2 hydrogenation and hydroformylation. Notably, monodentate PTA exhibited better activity and regioselectivity than common bidentate ligands, which might be ascribed to its built-in basic site and tris-chelated mode. Mechanistic studies indicate that the transformation proceeds through cascade steps, involving free HCOOH production through CO2 hydrogenation, fast release of CO, and rhodium-catalyzed conventional hydroformylation. Moreover, the unconventional hydroformylation pathway, in which HCOOAc acts as a direct C1 source, has also been proved feasible with superior regioselectivity than that of CO pathway.

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Kinetic behavior of soluble Pectinex Ultra SP-L converting sucrose into fructo-oligosaccharides in batch and continuous fashion

Progress in Agricultural Engineering Sciences ◽

10.1556/446.2020.00010 ◽

2020 ◽

Vol 16 (1) ◽

pp. 81-97

Author(s):

Zoltán Kovács ◽

Juraj Števek ◽

Miroslav Fikar ◽

Peter Czermak

Keyword(s):

Batch Reactor ◽

Continuous Production ◽

Value Added ◽

Batch Process ◽

Reaction Conditions ◽

Aspergillus Aculeatus ◽

A Value ◽

Industrial Implementation ◽

Production Scheme ◽

Experimental Runs

AbstractThe enzymatic conversion of sucrose to fructo-oligosaccharides (FOS) catalyzed by Pectinex Ultra SP-L, a commercial enzyme preparation from Aspergillus aculeatus, under free condition was studied. A mathematical analysis of the transfructosylation reactions was carried out to estimate the dynamic and steady-state performance of an enzyme membrane reactor (EMR) and to compare the continuous production scheme with the traditional batch process realized in stirred-tank reactor (STR). Kinetic parameters were identified simultaneously from a series of progress curves obtained from STR and EMR experimental runs. Model estimates appeared to fit well to experimental observations under the studied reaction conditions. Although conventional batch reactor outperforms EMR in terms of conversion, EMR compares favorably regarding productivity. The on-site industrial implementation of this technology might be attractive for food manufacturers aiming at utilizing a value-added sweetener mixture with prebiotic properties.

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Highly Selective Oxidation of 5-Hydroxymethylfurfural to 5-Hydroxymethyl-2-Furancarboxylic Acid by a Robust Whole-Cell Biocatalyst

Catalysts ◽

10.3390/catal9060526 ◽

2019 ◽

Vol 9 (6) ◽

pp. 526 ◽

Cited By ~ 8

Author(s):

Ran Cang ◽

Li-Qun Shen ◽

Guang Yang ◽

Zhi-Dong Zhang ◽

He Huang ◽

...

Keyword(s):

Selective Oxidation ◽

High Selectivity ◽

Value Added ◽

Catalytic Performance ◽

Resting Cells ◽

Fed Batch ◽

Reaction Conditions ◽

Whole Cell Biocatalyst ◽

Radiation Resistant ◽

First Time

Value-added utilization of biomass-derived 5-hydroxymethylfurfural (HMF) to produce useful derivatives is of great interest. In this work, extremely radiation resistant Deinococcus wulumuqiensis R12 was explored for the first time as a new robust biocatalyst for selective oxidation of HMF to 5-hydroxymethylfuroic acid (HMFCA). Its resting cells exhibited excellent catalytic performance in a broad range of pH and temperature values, and extremely high tolerance to HMF and the HMFCA product. An excellent yield of HMFCA (up to 90%) was achieved when the substrate concentration was set to 300 mM under the optimized reaction conditions. In addition, 511 mM of product was obtained within 20 h by employing a fed-batch strategy, affording a productivity of 44 g/L per day. Of significant synthetic interest was the finding that the D. wulumuqiensis R12 cells were able to catalyze the selective oxidation of other structurally diverse aldehydes to their corresponding acids with good yield and high selectivity, indicating broad substrate scope and potential widespread applications in biotechnology and organic chemistry.

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OPPORTUNITIES FOR STRATEGIC DEVELOPMENT OF BIO-ECONOMY IN THE FOOD AND TOURISM INDUSTRY

Knowledge International Journal ◽

10.35120/kij28051681g ◽

2018 ◽

Vol 28 (5) ◽

pp. 1681-1684

Author(s):

Georgi Toskov ◽

Ana Yaneva ◽

Stanko Stankov ◽

Hafize Fidan

Keyword(s):

National Level ◽

Value Added ◽

Tourism Industry ◽

Small Companies ◽

Food Sector ◽

Strategic Development ◽

Innovation Potential ◽

Wide Range ◽

Foreign Brands ◽

Value Added Products

The European Commission defines the bioeconomy as "the production of renewable biological resources and the conversion of these resources and waste streams into value added products, such as food, feed, bio-based products and bioenergy. Its sectors and industries have strong innovation potential due to their use of a wide range of sciences, enabling and industrial technologies, along with local and implied knowledge." The Bulgarian food industry faces a lot of challenges on the local and national level, which have direct influence on the structure of the production companies. Most of the enterprises from the food sector produce under foreign brands in order to be flexible partners to the large Bulgarian retail chains. The small companies from the food sector are not able to develop as an independent competitive producer on the territory of their local markets. This kind of companies rarely has a working strategy for positioning on new markets. In order to consolidate their already built positions for long period of time, the producers are trying to optimize their operations in a short term. However, the unclear vision of the companies for the business segment does not allow them to fully develop. Tourism in Bulgaria is a significant contributor to the country's economy.

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