Co-pyrolysis performances, synergistic mechanisms, and products of textile dyeing sludge and medical plastic wastes

Kinetics, Product Evolution, and Mechanism for the Pyrolysis of Typical Plastic Waste

“…The pyrolysis of plastic waste is complicated due to numerous parallel or consecutive reactions. , The global pyrolysis reaction can be represented and split as The detailed kinetic equation derivation process was reported in various studies. , Through the mathematic separation of variables (α and T ) in the kinetic equation of the solid-state reaction, integration of both sides leads to the eq . Therefore, the pyrolysis process can be exhibited via eq : where α is the conversion degree at the actual time t ; β is the heating rate, K min –1 ; E (α) is the apparent activation energy, kJ mol –1 ; A is the pre-exponential factor, min –1 ; R represents the universal gas constant; the f (α) is the kinetic model; the P ( u ) is an exponential integration of the temperature; and u = E / RT …”

“…The detailed kinetic equation derivation process was reported in various studies. 5,25 Through the mathematic separation of variables (α and T) in the kinetic equation of the solid-state reaction, integration of both sides leads to the eq 2. Therefore, the pyrolysis process can be exhibited via eq 2:…”

“…Besides, the CH 4 was the main gaseous product produced from copyrolysis of a tire with polyethylene and polypropylene. The pyrolyzer coupled with gas chromatography and mass spectrometry (Py-GC–MS) and TG-FTIR together analyzed the pyrolysis of plastic waste, which could obtain the information on evolution of gas products, functional groups, and hydrocarbon structure accurately. − Ding et al identified the pyrolysis characteristics of polyethylene and polypropylene via TG-FTIR and Py-GC–MS and found that the main hydrocarbons obtained from pyrolysis of polypropylene were C 4 C 24 alkenes and dialkene, whereas C 6 C 41 alkanes and C 8 C 41 1-alkenes were produced from pyrolysis of polyethylene. However, plastic waste have the characteristics of massive production, wide varieties, and complex component, and most previous studies generally pyrolyzed one or two representative components.…”

Methods for Natural and Synthetic Polymers Recovery from Textile Waste

“…In this way, textile waste can be transformed after pyrolysis into three products: char, pyrolytic oil, and syngas. This method has been studied extensively in an attempt to find an efficient method of recycling textile waste [ 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 ]. The mechanisms and the kinetics of cotton pyrolysis are well known [ 106 , 107 ].…”

“…One method to remedy this is co-pyrolysis of textile dyeing sludge with high-calorific plastic waste (medical plastic wastes from syringes, medical bottles). Polyolefin plastics with high calorific value and low ash content have an optimum pyrolysis temperature in the range of 400–550 °C [ 88 ].…”