Oxygen Trapping in Science and Industry

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Transcript Oxygen Trapping in Science and Industry

OXYGEN TRAPPING IN SCIENCE & INDUSTRY

Presented by :niloofar sadat fasih Superwizer:Dr.Ghazi asgar

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Today’s Overview

•Introduction of oxygen and its properties: 2 •Why O 2 Trapping is important in science ??

3 4 5 6 •Reasons to remove O 2 in industries??

•What is OXYGEN Trapping ??

•Important examples of oxygen trap •References

• •

Introduction of oxygen and its properties :

Landfill gas contains O 2 which enters the landfill as the landfill gas is withdrawn. O 2 may get added or introduced in the process of being used in gas dryers.

Why O2 Trapping is important in science??

Oxygen is a column killer . • in UHP gases, leaks allow O 2 to influx against the osmotic gradient. • O 2 can enter a gas line at any fitting.

GC needs pure N2 gas

O2 trap should be installed before the gas line enters the Gc.

Reasons to remove O2 in industries??

Types of oxygen contaminated natural gas streams Natural gas streams : Vacuum system • landfills • Vacuum oil recovery systems • Coal mine (gob gas) methane Tradition al pipeline systems •May contain only 100 ppm of oxygen

(LPG) &(LNG) contain some amount of O 2 • LPG blending processing with air to reduce its calorific value and achieve air balancing. • Many pipeline specifications require natural gas to contain less than 10 ppm of O 2 .

• • O2 is difficult to separate from natural gas.

Technology not available and developed High cost of such a removal project

 increase corrosion in pipelines exceed pipeline specifications

1) O 2 reacts with H2S to form sulfur. 2 H2S + 3 O2 2 H20 + 2 SO2 2) O2 creates salt in acid gas removal systems and affect the purge streams.

3) O2 cause corrosion drying plants in the steel by handling glycol solvents used in

Benefits of using O2 trap in purification natural gas  Prevent degradation of process Chemicals  decrease corrosion in pipelines  viable  Profitable

O 2 removal sys are rarely employed & usually abandoned or blended to meet pipeline specifications High capital costs Lack of industrial expertise Limited O removal range 2 Lack of O 2 removal system

What is OXYGEN Trapping ??

Oxygen removal catalyst is :

A chemical used in a reaction or process to remove O 2 from gas streams like :  N 2 , H 2 , Ar  Saturated hydrocarbons  Ethylene  Propylene And more.

Removal of oxygen from gas streams.

used for the purification of N 2 , Ar,CO 2 .

Adsorbents for O2 Removal

Metal catalysts Mixed-metal catalysts

Types of O2 trappers catalysts :

   Transition metal based deoxidizer (OX-RM) Hydro deoxygenation catalyst (OX-HR) Nickel based deoxidizer (OX-RN)

Important examples of oxygen trap

Transition Metal Based Deoxidizer OX-RM : • • Takes transition metal oxides as the promoter.

Designed for gas without hydrogenation directly • The ineffective deoxidizer can be used through regeneration.

OX-RM Properties :

• • O 2 -removal active : Min15 ml O2/g deoxidizer Remaining O 2 :Max.0.5ppm

• • • • Operation Conditions (with N2-H2 mixed gas reduction activation before usage) : Temperature : 200 ℃ Pressure : 0-6.0MPa

Feedstock gas inlet O 2 content : Max4000ppm Space velocity :0.5-3.0 hr

EX : Cu-0226 S Contain A copper oxide on a high surface area alumina sphere catalyst. Recovery Can be restored by regeneration Application Removing trace quantities of O 2 in inert gases at 25 ℃ .( Up to 90 % )

• • Hydro deoxygenation Catalyst OX-HR : Chemical composition :Pd-Al2O3 Removing O 2 and others.

from nitrogen, hydrogen,

Process conditions :

• Pressure: 0.1-10MPa • • • Temperature :100-210 ℃ Space velocity : 1000-2000 hr-1 • • Hydrogen/ Oxygen : >2 V/V Raw material :Nitrogen oxygen Activity index : O 2 < 10ppm.

EX : ( Puristar R0-20) Contain Robust , Pd on an alumina carrier.

Deoxo cat Application Removal of O2 and/or H2 from gas streams. Purification of N 2 , Ar , and CO2.

Nickel Based Deoxidizer OX-RN : • • • • Gases without hydrogenation directly. Use at ambient temperature.

Deoxidation activity : ≥20 mlO2/g deoxidizer Remaining O 2 :≤0.5 ppm

Operation (with N2-H2 mixed gas reduction activation before usage) : • • • • • Temperature : Room temperature to 200 ℃ Pressure :MPa 0~2.0

Feedstock gas inlet O 2 content : Max.4000ppm

Feedstock gas inlet dew point : Max.-60 ℃ Space velocity :100-300(gas),0.5-3.0(liquid) hr-1

DeOxo

  Removal of O 2 streams. and/or H 2 from gas The by-products generated at H 2 O and CO 2 .

Regenerator

  CuO catalyst tablet regenerate removal of O 2 , CO, H 2 , and other industrial gases and liquids.

Manganese (II) oxide supported on Celite

 Reduce the O2 in N2 streams to 1 ppn  chromatographic suitable  Non catalytic properties  enable to be packed directly into columns.