• Home
  • Blog
  • LPG Purification with zeolite 13X and 3A molecular sieve

LPG Purification with zeolite 13X and 3A molecular sieve

Table of Contents

Customer Background

zeolite 13X for Liquefied Petroleum Gas
Combined use of 3A & 13X molecular sieves with activated carbon in LPG purification removes H₂S, odor, and moisture, preventing pipeline blockage.

An LPG refinery faced issues with H₂S, mercaptans, moisture, and heavy hydrocarbons in its product stream—leading to equipment corrosion, odor, and catalyst poisoning. Traditional adsorbents couldn’t effectively remove all impurities. A three-stage adsorption process using activated carbon, 13X, and 3A molecular sieves was adopted for deep desulfurization, dehydration, and heavy hydrocarbon removal.

Process Overview

1.LPG Feed Composition & Targets

Impurity                            Before (ppm)                          Target (ppm) 
H₂S                                     200                                             < 0.5 
CH₃SH                                50                                               < 1                                                                              H₂O                                     100                                             < 5      
C5+                                     300                                             < 10 

2.Three-Stage Adsorption Design

  • Stage 1 – Activated Carbon:
    Removes C5+ hydrocarbons and partial sulfur compounds.
    Prevents clogging and protects downstream adsorbents.
  • Stage 2 – 13X Molecular Sieve:
    Removes H₂S, mercaptans, and moisture.
    High sulfur capacity (4–6 wt%), reduces water to <10 ppm.
  • Stage 3 – 3A Molecular Sieve:
    Final dehydration to <5 ppm H₂O.
    Selective to water, prevents LPG loss and freezing.

3.Regeneration Methods

  • Activated Carbon: Hot N₂ or steam (150–200°C)
  • Zeolite 13X: High-temp N₂ (250–300°C)
  • Zeolite 3A: Low-temp purge (180–220°C)
3A molecular sieve for LPG

Results

Impurity                                        Before (ppm)                              After (ppm)
H₂S                                                200                                                < 0.5
CH₃SH                                           50                                                  < 1
H₂O                                                100                                                < 3
C5+                                                300                                                < 10

Benefits

  • 30% lower operating cost than traditional processes.
  • Longer adsorbent life (Carbon: 1 yr, 13X: 3 yrs, 3A: 5 yrs).
  • Reduced waste—saves ~¥800,000/year in alkali treatment.
  •  Meets GB 11174-2011 and reduces SO₂ emissions.

Application Scope & Value

Ideal for   

  • LPG/natural gas purification (refineries, depots)
  • Raw gas (propylene, butene) purification
  • Autogas treatment

Optimization Tips:

  • Adjust desiccants 13X loading based on sulfur content.
  • Use TSA (Temperature Swing Adsorption) for efficiency.
  • Monitor pressure drop to prevent bed clogging.

Conclusion

The 13X + 3A + activated carbon process offers a cost-effective, environmentally friendly solution for ultra-deep LPG purification, making it suitable for high-standard energy and chemical applications.

Comments

Newest Blog

Hot Product

Tags

Related Blogs

As a leading molecular sieve manufacturer, we share the latest industry news and insights on adsorbents like molecular sieves, sieve powder, and activated alumina.

Scroll to Top

Get a Quote and Free Sample