Hydrothermal liquefaction of the brown macro-alga Laminaria Saccharina: Effect of reaction conditions on product distribution and composition

2011 ◽  
Vol 102 (7) ◽  
pp. 4876-4883 ◽  
Author(s):  
K. Anastasakis ◽  
A.B. Ross
1995 ◽  
Vol 60 (1) ◽  
pp. 104-114 ◽  
Author(s):  
Boyd L. Earl ◽  
Richard L. Titus

Previous reports on the thermal or CO2-laser induced decomposition of trichloroethylene have identified only one condensible product, hexachlorobenzene (in addition to HCl and mono- and dichloroacetylene). We have found that trichloroethylene vapor exposed to cw irradiation on the P(24) line of the (001 - 100) band of the CO2 laser at incident power levels from 8 - 17 W produces numerous products, of which the 13 major ones have been identified using IR, GC/MS, GC/FTIR, and NMR methods. All of these products have 4, 6, or 8 carbons, are highly unsaturated, and are completely chlorinated or contain a single hydrogen. C4HCl5 and C6Cl6 isomers (three of each) account for S 55% to 85% of total products (based on peak areas in the total ion chromatograms in GC/MS runs), depending on reaction conditions. In addition to characterizing the products, we discuss the dependence of the product distribution on laser power, irradiation time, and cell geometry, and we outline a possible mechanism.


Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ajinkya More ◽  
Thomas Elder ◽  
Zhihua Jiang

Abstract This review discusses the main factors that govern the oxidation processes of lignins into aromatic aldehydes and acids using hydrogen peroxide. Aromatic aldehydes and acids are produced in the oxidative degradation of lignin whereas mono and dicarboxylic acids are the main products. The stability of hydrogen peroxide under the reaction conditions is an important factor that needs to be addressed for selectively improving the yield of aromatic aldehydes. Hydrogen peroxide in the presence of heavy metal ions readily decomposes, leading to minor degradation of lignin. This degradation results in quinones which are highly reactive towards peroxide. Under these reaction conditions, the pH of the reaction medium defines the reaction mechanism and the product distribution. Under acidic conditions, hydrogen peroxide reacts electrophilically with electron rich aromatic and olefinic structures at comparatively higher temperatures. In contrast, under alkaline conditions it reacts nucleophilically with electron deficient carbonyl and conjugated carbonyl structures in lignin. The reaction pattern in the oxidation of lignin usually involves cleavage of the aromatic ring, the aliphatic side chain or other linkages which will be discussed in this review.


2020 ◽  
Vol 317 ◽  
pp. 124033
Author(s):  
Guanyi Chen ◽  
Yingying Yu ◽  
Wanqing Li ◽  
Beibei Yan ◽  
Kaige Zhao ◽  
...  

RSC Advances ◽  
2021 ◽  
Vol 11 (43) ◽  
pp. 26763-26772
Author(s):  
Jian Yang ◽  
Chen Hong ◽  
Yi Xing ◽  
Zixuan Zheng ◽  
Zaixing Li ◽  
...  

In this study, the antibiotic residue was used as a raw material to catalyze hydrothermal liquefaction (HTL) in an ethanol–water system to prepare bio-oil.


1984 ◽  
Vol 57 (2) ◽  
pp. 275-283 ◽  
Author(s):  
R. Vukov

Abstract The study of the halogenation behavior of butyl rubber model compounds has brought about a better understanding of the behavior of these systems. It has been established that the presence of methyl groups, in a position B to the reaction site in the butyl rubber model compound, profoundly influences the course of halogenation. Due to the steric hindrance imposed by these groups, both the products of chlorination and bromination deviate from patterns typical of other trisubstituted alkenes. In the case of chlorination, this deviation is demonstrated by the absence of addition products of chlorine across the double bond. In the case of bromination reactions, the change in product distribution is even more dramatic. Thus, substitution products normally not observed in bromination reactions of other trisubstituted alkenes become predominant products found in yields of between 70–90% depending on the precise reaction conditions. The behavior of the butyl model compound appears to be entirely consistent with the behavior of butyl rubber itself; the model compound approach is therefore a valuable tool for use in the basic study of this type of system.


Fuel ◽  
2020 ◽  
Vol 277 ◽  
pp. 118146 ◽  
Author(s):  
Kodanda Phani Raj Dandamudi ◽  
Kato Muhammed Luboowa ◽  
Maymary Laideson ◽  
Tessa Murdock ◽  
Mark Seger ◽  
...  

2014 ◽  
Vol 798-799 ◽  
pp. 205-210
Author(s):  
Jairo Alberto Gomez-Cuaspud ◽  
Martin Schmal

We investigated the synthesis of nanosized Co3O4 oxide by the polymerization-combustion technique, with different concentrations (3, 12 and 25% w/w) in the ethanol oxidation reaction. Characterization was done by X-ray fluorescence analysis, X-ray diffraction, temperature programmed reduction, scanning and transmission electronic microscopy and CO and H2 chemisorption. Principal results from physicochemical characterization show that the concentration of the metal oxide influence the product distribution and selectivity under isothermal conditions at 420 °C showed the formation of intermediate etoxi-species and preferential dehydrogenation reaction on stream of material. Specific concentrations result in high conversions and H2 selectivity under present reaction conditions.


2019 ◽  
Vol 6 (11) ◽  
pp. 191165 ◽  
Author(s):  
Kayla A. DeNike ◽  
Stefan M. Kilyanek

Deoxydehydration (DODH) is an important reaction for the upconversion of biomass-derived polyols to commodity chemicals such as alkenes and dienes. DODH can be performed by a variety of early metal-oxo catalysts incorporating Re, Mo and V. The varying reduction methods used in the DODH catalytic cycle impact the product distribution, reaction mechanism and the overall yield of the reaction. This review surveys the reduction methods commonly used in homogeneous DODH catalyst systems and their impacts on yield and reaction conditions.


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