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Title: Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor

Abstract

The gas-solid reaction and breakthrough curves in the fixed-bed reactor are of great importance, and being influenced by a number of factors makes the prediction of these factors a difficult problem. In this study, the reaction rate between solid sorbents and hydrogen chloride gas at high temperature was first investigated. On the basis of a fixed-bed reactor, the experimental results were analyzed by the shrinking core model of diffusion and surface chemical reaction control. The results showed that reaction rates of two sorbents with hydrogen chloride gas were controlled by the combination of the surface chemical reaction and diffusion of product layers, and the reaction rates nearly keep constant within 15 h of the initial reaction period and then decrease gradually. The results of the breakthrough curves show that solid sorbents in the fixed-bed reactor are capable of reducing the HCl level to near-zero levels at 550{sup o}C. The experimental results and prediction for breakthrough curves are in good agreement for two sorbents. 13 refs., 9 figs., 7 tabs.

Authors:
; ; ;  [1]
  1. Shanghai University of Electric Power, Shanghai (China). Department of Environment Engineering
Publication Date:
OSTI Identifier:
20700952
Resource Type:
Journal Article
Resource Relation:
Journal Name: Energy and Fuels; Journal Volume: 19; Journal Issue: 6; Other Information: doubinlin@hotmail.com
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; HYDROCHLORIC ACID; PACKED BEDS; ADSORBENTS; GASES; CHEMICAL REACTORS; CHEMICAL REACTION KINETICS; DIFFUSION; BENCH-SCALE EXPERIMENTS; DECHLORINATION; TEMPERATURE DEPENDENCE; CHLORINE; ADSORPTION; PARAMETRIC ANALYSIS; HOT GAS CLEANUP; REMOVAL; SORPTIVE PROPERTIES; TEMPERATURE RANGE 0400-1000 K

Citation Formats

Binlin Dou, Bingbing Chen, Jinsheng Gao, and Xingzhong Sha. Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor. United States: N. p., 2005. Web.
Binlin Dou, Bingbing Chen, Jinsheng Gao, & Xingzhong Sha. Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor. United States.
Binlin Dou, Bingbing Chen, Jinsheng Gao, and Xingzhong Sha. Thu . "Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor". United States. doi:.
@article{osti_20700952,
title = {Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor},
author = {Binlin Dou and Bingbing Chen and Jinsheng Gao and Xingzhong Sha},
abstractNote = {The gas-solid reaction and breakthrough curves in the fixed-bed reactor are of great importance, and being influenced by a number of factors makes the prediction of these factors a difficult problem. In this study, the reaction rate between solid sorbents and hydrogen chloride gas at high temperature was first investigated. On the basis of a fixed-bed reactor, the experimental results were analyzed by the shrinking core model of diffusion and surface chemical reaction control. The results showed that reaction rates of two sorbents with hydrogen chloride gas were controlled by the combination of the surface chemical reaction and diffusion of product layers, and the reaction rates nearly keep constant within 15 h of the initial reaction period and then decrease gradually. The results of the breakthrough curves show that solid sorbents in the fixed-bed reactor are capable of reducing the HCl level to near-zero levels at 550{sup o}C. The experimental results and prediction for breakthrough curves are in good agreement for two sorbents. 13 refs., 9 figs., 7 tabs.},
doi = {},
journal = {Energy and Fuels},
number = 6,
volume = 19,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 2005},
month = {Thu Dec 01 00:00:00 EST 2005}
}
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  • A distillation fraction of a coal-derived liquid (tar) was cracked over a char-dolomite mixture, calcined dolomite, and silicon carbide in a fixed-bed reactor. The char-dolomite mixture (FWC) was produced from Pittsburgh No. 8 coal and dolomite in a Foster Wheeler carbonizer. The experiments were conducted under nitrogen and simulated coal gas (SCG), which was a mixture of CO, CO{sub 2}, H{sub 2}S, CH{sub 4}, N{sub 2}, and steam, at 1 and 17 atm. The conversion over these materials under nitrogen was much higher at 17 atm than at 1 atm. At higher pressures, tar molecules were trapped in the poresmore » of the bed material and underwent secondary reactions, resulting in the formation of excess char. However, when nitrogen was replaced by SCG, the reactions that induce char formation were suppressed, thus increasing the yield of gaseous products. The analysis of the gaseous products and the spent bed materials for organic and inorganic carbons suggested that the product distribution can be altered by changing the carrier gas, temperature, and pressure.« less