Development and Industrialization of the Ethylbenzene Production Technologies from Dilute Ethylene in FCC Dry Gas

2011 ◽  
Vol 233-235 ◽  
pp. 1708-1713
Author(s):  
Xiang Xue Zhu ◽  
Fu Cun Chen ◽  
Jie An ◽  
Peng Zeng ◽  
Long Ya Xu
Keyword(s):  
Gas Phase ◽  
Energy Cost ◽  
Low Energy ◽  
Alkylation Reaction ◽  
Chemical Physics ◽  
The Novel ◽  
Feed Addition ◽  
Production Technologies ◽  
Operation Results ◽  
Alkylation Catalyst

This article demonstrates the design and industrial operation results of the ethylbenzene(EB) production technology from FCC dry gas by a combination of gas-phase alkylation and liquid-phase transalkylation, developed and commercialized by Dalian Institute of Chemical Physics (DICP), CAS. Based on the high active modified ZSM-5/ZSM-11 co-crystalline zeolite alkylation catalyst and modified β zeolite transalkylation catalyst, both the alkylation and transalkylation reactions are performed under much milder conditions, resulting in low energy cost and low content of xylenes impurities in the EB product. Also, the novel process for EB production, developed by DICP recently, through alkylation of dilute ethylene with gas-liquid mixed phase benzene and transalkylation feed is optimized. The results show that the transalkylation feed addition into the middle-lower part of the reactor improves the EB selectivity from about 90% to more than 99%, and the alkylation and transalkylation reactions are unified into a single reactor. Moreover, the alkylation reaction temperature decreases from more than 320 °C to about 170 °C, and the content of the xylenes impurities in the EB product is further decreased to less than 100 ppm.

Recycling lead from spent lead pastes using oxalate and sodium oxalate and preparation of novel lead oxide for lead-acid batteries

RSC Advances ◽  
2015 ◽  
Vol 5 (115) ◽  
pp. 94895-94902 ◽  
Author(s):  
Cheng Ma ◽  
Yuehong Shu ◽  
Hongyu Chen
Keyword(s):  
Energy Cost ◽  
Lead Oxide ◽  
Low Energy ◽  
Sodium Oxalate ◽  
Lead Acid Batteries ◽  
Smelting Method ◽  
Lead Acid

A sustainable method, with minimal pollution and low energy cost in comparison with the conventional smelting method, is proposed for treating components of spent lead acid batteries with oxalate and sodium oxalate.

Microwave Torch Plasmas for Decomposition of Gaseous Pollutants

2004 ◽  
Vol 7 (1) ◽  
Author(s):  
Mariusz Jasiński ◽  
Jerzy Mizeraczyk ◽  
Zenon Zakrzewski
Keyword(s):  
Atmospheric Pressure ◽  
Energy Cost ◽  
Gas Flow ◽  
Coaxial Line ◽  
Low Energy ◽  
Gaseous Pollutants ◽  
Gas Flow Rate ◽  
Torch Discharge ◽  
Volatile Organic ◽  
Moderate Power

AbstractResults of the study of decomposition of volatile organic compounds (VOCs including Freons) in their mixtures with either synthetic air or nitrogen, and nitrogen oxides NOx in their mixtures with N2 or Ar in low (~ 100 W) and moderate-power (200-400 W) microwave torch plasmas at atmospheric pressure are presented. Three types of microwave torch discharge (MTD) generators, i.e. the low-power coaxial-line-based MID, the moderate-power waveguide-based coaxial-line MTD and the moderate-power waveguide-based MTD generators were used. The gas flow rate and microwave power (2.45 GHz) delivered to the discharge were in the range of 1÷3 l/min and 100÷ 400 W, respectively. Concentrations of the processed gaseous pollutants usually were from several up to several tens percent. The energy efficiency of decomposition of several gaseous pollutants reached 1000 g/kWh. It was found that the microwave torch plasmas fully decomposed the pollutants at relatively low energy cost. This suggests that the MTD plasma can be a useful tool for decomposition of highly-concentrated gaseous pollutants.

scholarly journals Low-energy positron scattering from gas-phase uracil

2014 ◽  
Vol 68 (7) ◽  
Author(s):  
Jan Franz ◽  
Franco A. Gianturco ◽  
Isabella Baccarelli
Keyword(s):  
Gas Phase ◽  
Low Energy ◽  
Positron Scattering

scholarly journals The effect of adenine protonation on RNA phosphodiester backbone bond cleavage elucidated by deaza-nucleobase modifications and mass spectrometry

2019 ◽  
Vol 47 (14) ◽  
pp. 7223-7234 ◽  
Author(s):  
Elisabeth Fuchs ◽  
Christoph Falschlunger ◽  
Ronald Micura ◽  
Kathrin Breuker
Keyword(s):  
Mass Spectrometry ◽  
Gas Phase ◽  
Vibrational Excitation ◽  
Bond Cleavage ◽  
Low Energy ◽  
Biological Processes ◽  
Phosphodiester Backbone ◽  
Collisionally Activated Dissociation ◽  
Rna Backbone ◽  
Ionic Hydrogen Bonds

Abstract The catalytic strategies of small self-cleaving ribozymes often involve interactions between nucleobases and the ribonucleic acid (RNA) backbone. Here we show that multiply protonated, gaseous RNA has an intrinsic preference for the formation of ionic hydrogen bonds between adenine protonated at N3 and the phosphodiester backbone moiety on its 5′-side that facilitates preferential phosphodiester backbone bond cleavage upon vibrational excitation by low-energy collisionally activated dissociation. Removal of the basic N3 site by deaza-modification of adenine was found to abrogate preferential phosphodiester backbone bond cleavage. No such effects were observed for N1 or N7 of adenine. Importantly, we found that the pH of the solution used for generation of the multiply protonated, gaseous RNA ions by electrospray ionization affects phosphodiester backbone bond cleavage next to adenine, which implies that the protonation patterns in solution are at least in part preserved during and after transfer into the gas phase. Our study suggests that interactions between protonated adenine and phosphodiester moieties of RNA may play a more important mechanistic role in biological processes than considered until now.

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