Method for using polyolefin plastic to prepare micromolecule alkene

A polyolefin and small molecule technology, which is applied in the thermal cracking/catalytic cracking-microwave cracking two-step method to recover polyolefin plastics and produce small molecule olefins, can solve the problems of limiting the scope of application of cracking raw materials, and achieve higher cracking temperature, The effect of improving heating efficiency and low energy consumption

Inactive Publication Date: 2017-03-22
INST OF PROCESS ENG CHINESE ACAD OF SCI
View PDF17 Cites 36 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This inevitably limits the scope of

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for using polyolefin plastic to prepare micromolecule alkene
  • Method for using polyolefin plastic to prepare micromolecule alkene
  • Method for using polyolefin plastic to prepare micromolecule alkene

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0058] Example 1

[0059] In this embodiment, LDPE is used as a raw material to prepare small molecular olefins, figure 1 It is a flow chart of the method for preparing small molecular olefins with polyolefin plastics, and the specific steps are as follows:

[0060] (1) Cracking:

[0061] like figure 2 As shown, before the cracking reaction, a nitrogen purge device 203 is used to purge the semi-continuous mild cracking device to remove the air in the device. First, use the mass flow meter 204 to control the nitrogen flow rate to 50ml / min, and purge for 20 minutes; then set the nitrogen flow rate to 20ml / min, and use nitrogen purge throughout the cracking reaction. The LDPE cleaned and pulverized particles are transported into the reactor 201, and the temperature control device 208 is used to control the power of the heating device 202, so that the temperature rise rate of the reactor 201 is 5°C / min, and the reactor 201 is monitored in real time through the temperature meas...

Example Embodiment

[0068] Example 2

[0069] In this example, LDPE is used as raw material to prepare small molecular olefins. The specific steps differ from Example 1 in that the mass ratio of water to liquid product b is 0.5:1, the cracking temperature is 1100°C, and the mixture of liquid product b and water The residence time of the feedstock in the cracking zone 302 is 0.005s.

[0070] The results of this embodiment are shown in Table 2-5. As can be seen from Table 3, since the cracking temperature of this embodiment is higher than that of Example 1, the molar content of ethylene and propylene in the gas product c is higher than that of Example 1.

[0071]It can be seen from Table 4 that the total mass yield of the gas product c in this embodiment is 75%, and the mass yield of ethylene and propylene is 52.32%, which is lower than that of Example 1. This is because compared with Example 1, the residence time of the mixture of liquid product b and water in the cracking zone 302 is shorter an...

Example Embodiment

[0072] Example 3

[0073] In this example, LDPE is used as a raw material to prepare small molecular olefins. The difference between the specific steps and Example 1 is that the cracking temperature is 700°C.

[0074] The results of this embodiment are shown in Table 2-5. As can be seen from Table 4, the total mass yield of gas product c of the present embodiment is only 52.02%, wherein the mass yield of ethylene and propylene is 25.33%, which is significantly lower than that of Example 1, indicating that when the microwave cracking temperature is too low, the cracking Insufficient response.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a method for using polyolefin plastic to prepare micromolecule alkene. According to the method, at first, the polyolefin plastic is cracked, then a liquid/ waxy product obtained through cracking is mixed with selectable liquid petroleum hydrocarbon and water, and the mixture is subjected to microwave pyrolysis to obtain micromolecule alkene. The method specifically comprises the following steps that the polyolefin plastic is conveyed into a moderate cracking device to be cracked, and a gas product a and the liquid/ waxy product b are obtained through gas-liquid separation; the product b is mixed with selectable liquid petroleum hydrocarbon and the water, and the mixture serves as a microwave pyrolysis raw material; and the microwave pyrolysis raw material is mixed with the water, the mixture is conveyed into a microwave pyrolysis device, after microwave pyrolysis is carried out, the mixture is quenched to be 500 DEG C or below, and a cracked product is obtained. According to the method, microwave heating of hydrocarbon raw materials insensitive to microwaves is achieved, the source of the raw material for preparing micromolecule alkene is expanded, by means of the inner heating characteristic of microwave heating, the cracking temperature is increased, the cracking efficiency is improved, and energy consumption is lower than that of a traditional pipe cracking furnace.

Description

technical field [0001] The invention belongs to the field of cracking polyolefin plastics, and relates to a method for preparing small molecular olefins from polyolefin plastics, in particular to a method for recovering polyolefin plastics by thermal cracking / catalytic cracking-microwave cracking two-step method to prepare small molecular olefins method. Background technique [0002] Polyolefins are bulk plastic products with a wide range of uses. Statistics show that in 2011, China's plastic consumption has reached nearly 60 million tons, accounting for more than a quarter of the world's total consumption, and China has become the world's largest plastic consumer. At the same time, due to the generally short service life of plastic products, especially plastic packaging, a large amount of waste plastics has caused increasingly serious "white pollution". In waste plastics, polyolefins represented by polyethylene and polypropylene usually account for 60-70%, and the treatme...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C10G1/10C10G9/24
CPCC10G1/10C10G9/24C10G2300/805C10G2400/20
Inventor 景晓东温浩徐志宏
Owner INST OF PROCESS ENG CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products