Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y

Ethylene is an important raw material for the downstream petrochemical industry. Significantly, with the shortage of natural resource and fossil fuel-derived energy, catalytic dehydration of ethanol to ethylene route has become compelling, and therefore has been drawing attention lately. In this wor...

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Main Author:	Soh, Jiah Chee
Format:	Thesis
Language:	English
Published:	2017
Subjects:	TP Chemical technology
Online Access:	http://umpir.ump.edu.my/id/eprint/18157/19/Ethylene%20production%20from%20ethanol%20dehydration%20over%20non-%20modified%20and%20phosphorus%20modified%20zeolite%20Y.pdf
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spelling	my-ump-ir.181572021-12-15T00:10:49Z Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y 2017-02 Soh, Jiah Chee TP Chemical technology Ethylene is an important raw material for the downstream petrochemical industry. Significantly, with the shortage of natural resource and fossil fuel-derived energy, catalytic dehydration of ethanol to ethylene route has become compelling, and therefore has been drawing attention lately. In this work, commercial zeolite Y was screened to identify the best Si/Al ratio as well as analyze the catalysts’ physicochemical properties. Besides, zeolite Y and phosphorus modified zeolite Y were employed as catalysts to study the effect of reaction temperatures and ethanol partial pressure on dehydration of ethanol to form ethylene. Towards achieving this goal, zeolite Y with various Si/Al ratio (5.1:1. 12:1, 30:1, 60:1 and 80:1) were firstly screened; zeolite Y with Si/Al ratio 80:1, coded H-Y (80) demonstrated the best catalytic performance with high ethanol conversion and ethylene selectivity (73.0% and 99.5% respectively) at 773 K. Subsequently, wet impregnation technique was employed to modify the H-Y (80) with phosphoric acid solution. For activity evaluation, a bench-scale fixed-bed reactor was employed and only the gaseous product from ethanol dehydration was collected and subjected to GC analysis. From the results obtained, BET specific surface area of fresh catalysts showed decreasing trend with increasing phosphorus loadings. Moreover, phosphorus modification on H-Y (80) can decrease the volume of micropores and mesopores due to channel blocking by PO43-. In addition, the NH3-TPD analysis showed that the increase in phosphorus loading had increased the moderate-strong acid sites. Among all the phosphorus modified H-Y (80), 3.15P/H-Y (80) was shown to exhibit the highest ethanol dehydration activity, where the conversion of ethanol at 773 K was 66.45%. The ethylene selectivity over all the catalysts was almost similar, easily attaining values of greater than 88.0%. Based on the N2 physisorption and SEM-EDX analysis of spent catalysts, it can be confirmed that the there was less carbon deposition on phosphorus modified H-Y (80) and demonstrated a better stability during the reaction although this has come at the expense of reduced activity. In conclusion, H-Y (80) showed the best catalytic activity among all the tested zeolite Y, and phosphorus modification decreased the BET specific area but increase the strength of acid sites in the catalysts. From the results, high reaction temperature and low ethanol partial pressure favour ethanol dehydration by H-Y (80). 2017-02 Thesis http://umpir.ump.edu.my/id/eprint/18157/ http://umpir.ump.edu.my/id/eprint/18157/19/Ethylene%20production%20from%20ethanol%20dehydration%20over%20non-%20modified%20and%20phosphorus%20modified%20zeolite%20Y.pdf pdf en public masters Universiti Malaysia Pahang Faculty of Chemical and Natural Resources Engineering
institution	Universiti Malaysia Pahang Al-Sultan Abdullah
collection	UMPSA Institutional Repository
language	English
topic	TP Chemical technology
spellingShingle	TP Chemical technology Soh, Jiah Chee Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y
description	Ethylene is an important raw material for the downstream petrochemical industry. Significantly, with the shortage of natural resource and fossil fuel-derived energy, catalytic dehydration of ethanol to ethylene route has become compelling, and therefore has been drawing attention lately. In this work, commercial zeolite Y was screened to identify the best Si/Al ratio as well as analyze the catalysts’ physicochemical properties. Besides, zeolite Y and phosphorus modified zeolite Y were employed as catalysts to study the effect of reaction temperatures and ethanol partial pressure on dehydration of ethanol to form ethylene. Towards achieving this goal, zeolite Y with various Si/Al ratio (5.1:1. 12:1, 30:1, 60:1 and 80:1) were firstly screened; zeolite Y with Si/Al ratio 80:1, coded H-Y (80) demonstrated the best catalytic performance with high ethanol conversion and ethylene selectivity (73.0% and 99.5% respectively) at 773 K. Subsequently, wet impregnation technique was employed to modify the H-Y (80) with phosphoric acid solution. For activity evaluation, a bench-scale fixed-bed reactor was employed and only the gaseous product from ethanol dehydration was collected and subjected to GC analysis. From the results obtained, BET specific surface area of fresh catalysts showed decreasing trend with increasing phosphorus loadings. Moreover, phosphorus modification on H-Y (80) can decrease the volume of micropores and mesopores due to channel blocking by PO43-. In addition, the NH3-TPD analysis showed that the increase in phosphorus loading had increased the moderate-strong acid sites. Among all the phosphorus modified H-Y (80), 3.15P/H-Y (80) was shown to exhibit the highest ethanol dehydration activity, where the conversion of ethanol at 773 K was 66.45%. The ethylene selectivity over all the catalysts was almost similar, easily attaining values of greater than 88.0%. Based on the N2 physisorption and SEM-EDX analysis of spent catalysts, it can be confirmed that the there was less carbon deposition on phosphorus modified H-Y (80) and demonstrated a better stability during the reaction although this has come at the expense of reduced activity. In conclusion, H-Y (80) showed the best catalytic activity among all the tested zeolite Y, and phosphorus modification decreased the BET specific area but increase the strength of acid sites in the catalysts. From the results, high reaction temperature and low ethanol partial pressure favour ethanol dehydration by H-Y (80).
format	Thesis
qualification_level	Master's degree
author	Soh, Jiah Chee
author_facet	Soh, Jiah Chee
author_sort	Soh, Jiah Chee
title	Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y
title_short	Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y
title_full	Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y
title_fullStr	Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y
title_full_unstemmed	Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y
title_sort	ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite y
granting_institution	Universiti Malaysia Pahang
granting_department	Faculty of Chemical and Natural Resources Engineering
publishDate	2017
url	http://umpir.ump.edu.my/id/eprint/18157/19/Ethylene%20production%20from%20ethanol%20dehydration%20over%20non-%20modified%20and%20phosphorus%20modified%20zeolite%20Y.pdf
_version_	1783732028633513984

Ethylene production from ethanol dehydration over non- modified and phosphorus modified zeolite Y

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