Table 5. Ni/Al₂O₃ Catalysts Reported in the Literature for the Pyrolysis and In-line Steam Reforming of Plastic Wastes.

Catalys	Feed	Preparation methoda	Reactor configuration	Operating conditionsb	H2 conc. (vol %)	H2 prod. (wt %)	Ref.
Ni/Al2O3	PP	commercial C11-NK	fluidized/fluidized (1 g min–1)	TP = 600 °C	70.0	34.0	Czernik and French54
				TR = 850 °C
				S/C = 4.6
11Ni/Al2O3	HDPE	commercial (G90 LDP)	spouted/fixed (0.75 g min–1)	TP = 500 °C	71.0	34.5	Erkiaga et al.97
				TR = 700 °C
				S/C = 3.1
11Ni/Al2O3	HDPE	commercial (G90 LDP)	spouted/fluidized (0.6 g min–1)	TP = 500 °C	72.7	38.1	Barbarias et al.44
				TR = 700 °C
				S/C = 3.9
11Ni/Al2O3	HDPE	commercial (G90 LDP)	spouted/fluidized (0.75 g min–1)	TP = 500 °C	69.8	37.3	Barbarias et al.56,99
				TR = 700 °C
				S/C = 3.1
11Ni/Al2O3	PP	commercial (G90 LDP)	spouted/fluidized (0.75 g min–1)	TP = 500 °C	70.1	34.8	Barbarias et al.56
				TR = 700 °C
				S/C = 3.1
11Ni/Al2O3	PS	commercial (G90 LDP)	spouted/fluidized (0.75 g min–1)	TP = 500 °C	65.4	29.1	Barbarias et al.46,56
				TR = 700 °C
				S/C = 2.9
11Ni/Al2O3	PET	commercial (G90 LDP)	spouted/fluidized (0.75 g min–1)	TP = 500 °C	63.6	18.2	Barbarias et al.56
				TR = 700 °C
				S/C = 4.3
11Ni/Al2O3	HDPE 48 wt %; PP, 35 wt %; PS, 9 wt %; PET: 8 wt %	commercial (G90 LDP)	spouted/fluidized (0.75 g min–1)	TP = 500 °C	63.9	32.5	Barbarias et al.56
				TR = 700 °C
				S/C = 3.2
10Ni/Al2O3	PP	wi	spouted/fluidized (0.75 g min–1)	TP = 500 °C	70.8	34.1	Arregi et al.55
				TR = 700 °C
				S/C = 3.1
Ni/Al2O3 (1:1 molar ratio)	PP	cp	fixed/fixed (1 g)	TP = 500 °C	66.6	24.8	Wu and Williams150
				TR = 800 °C
				steam = 4.74 g h–1
10Ni/Al2O3	PP	wi	fixed/fixed (1 g)	TP = 500 °C	56.3	11.5	Wu and Williams164
				TR = 800 °C
				steam = 4.74 g h–1
10Ni/Al2O3	PE	wi	fixed/nonthermal plasma (1 g)	TP = 500 °C		0.9	Aminu et al.165
				TR = 250 °C
				steam = 4 g h–1
10Ni/Al2O3	HDPE	wi, cp, sg	fixed/fixed (1 g)	TP = 500 °C	62.0	12.1	Yao et al.63
				TR = 800 °C
				steam = 6 g h–1
10Ni/Al2O3	PP	wi, cp, sg	fixed/fixed (1 g)	TP = 500 °C	59.4	13.4	Yao et al.63
				TR = 800 °C
				steam = 6 g h–1
10Ni/Al2O3	PS	wi, cp, sg	fixed/fixed (1 g)	TP = 500 °C	57.9	12.5	Yao et al.63
				TR = 800 °C
				steam = 6 g h–1
5 Ni/Al2O3	PP	wi	fixed/fixed (1 g)	TP = 500 °C	49.5	6.9	Acomb et al.163
				TR = 800 °C
				steam = 4.74 g h–1
5 Ni/Al2O3	LDPE	wi	fixed/fixed (1 g)	TP = 500 °C	53.1	9.2	Acomb et al.163
				TR = 800 °C
				steam = 4.74 g h–1
5 Ni/Al2O3	PS	wi	fixed/fixed (1 g)	TP = 500 °C	60.0	7.4	Acomb et al.163
				TR = 800 °C
				steam = 4.74 g h–1

^awi, Wetness impregnation; cp, co-precipitation; sg, sol–gel; ie, ion-exchange.

^bT_P = Pyrolysis temperature; T_R = reforming temperature.