Method for simultaneously achieving two-stage catalytic pyrolysis, debromination and light-fraction conversion of pyrolyzed oil of waste printed circuit boards

Abstract

The invention discloses a method for simultaneously achieving two-stage catalytic pyrolysis, debromination and light-fraction conversion of pyrolyzed oil of waste printed circuit boards. The method comprises the following steps that S1, the waste printed circuit boards are crushed, nonmetal powder is extracted and put into a first temperature zone of a two-stage heating pyrolyzing furnace, and meanwhile a composite catalyst is put into a second temperature zone of the two-stage heating pyrolyzing furnace; S2, the first temperature zone and the second temperature zone are heated simultaneously, and the pyrolyzed oil is collected after pyrolyzation is completed, wherein according to heating conditions, the first temperature zone is heated to 400 DEG C to 450 DEG C, the temperature is kept for 1 h to 1.5 h, the second temperature zone is heated to 450 DEG C to 500 DEG C, and the temperature is kept for 1.5 h to 2.5 h. The composite catalyst is prepared from, by weight, 35-65 parts of Al2O3 and 65-35 parts of CaCO3. According to the method for simultaneously achieving two-stage catalytic pyrolysis, debromination and light-fraction conversion of the pyrolyzed oil of the waste printed circuit boards, efficient dehalogenation and light-fraction conversion of the pyrolyzed oil of the waste printed circuit boards can be achieved simultaneously, and the technical bottleneck of resource recovery of the nonmetal powder of the waste printed circuit boards is solved.

Description

technical field [0001] The invention belongs to the technical field of recycling waste circuit boards, and in particular relates to a two-stage catalytic pyrolysis method for simultaneous debromination and lightening of waste circuit board pyrolysis oil. Background technique [0002] Printed Circuit Boards (PCB for short) is a thermosetting composite material. As the core component of electronic products, it is widely used in many industrial fields such as electronic components and electric control. With the development of science and technology, the frequency of replacement and elimination of electronic products has accelerated, leading to an increase in the amount of PCB waste. According to the estimate of the United Nations University, in 2005, the e-waste in EU countries was as high as 9.1 million tons, and it was increasing at a rate of 2.5% to 2.7% every year. In 2008, China's output of printed circuit boards was as high as 26% of the world's total, occupying the firs...

AI Technical Summary

Problems solved by technology

The traditional treatment methods of WPCBs mainly include mechanical physical method, chemical method and pyrometallurgy, etc. The purpose is to recover the valuable metals in them. The remaining non-metallic parts are not fully utilized, and it is easy to produce a large amount of waste gas, waste liquid and waste residue, which is harmful to the environment. cause secondary pollution

The pyrolysis technology can effectively separate metals, organic matter and glass fibers, and has attracted much attention and research in recent years, especially the vacuum pyrolysis treatment technology. However, WPCBs contain halogen-containing flame retardants, resulting in thermal Pyrolysis oil contains a large amount of bromine-containing substances, which seriously hinders the further utilization of pyrolysis oil