Analisis Eksperimental Konversi Bahan Bakar dari Sampah Plastik HDPE (High-Density Polyethylene) Menggunakan Metode Thermal Pyrolysis dan Catalytic Pyrolysis dengan Heat Pipe sebagai Passive Cooling System = An Experimental Analysis of Fuel Conversion from HDPE (High-Density Polyethylene) Waste Using Thermal Pyrolysis and Catalytic Pyrolysis Methods with Heat Pipe as Passive Cooling System.