Abstrak 
Produksi sampah plastik di Indonesia sebesar 5,4 juta ton per tahun, berdasarkan data statistik persampahan domestik Indonesia jumlah sampah plastik tersebut sebesar 14% merupakan total produksi sampah di Indonesia. Pencampuran limbah plastik LDPE dengan tempurung kelapa yang memiliki nilai kalor tinggi dan kadar volatile matter cukup rendah dinilai sangat berpotensi untuk dijadikan sumber energi alternative yaitu briket. Tujuan dari penelitian ini adalah 1) Mengetahui pengaruh persentase pencampuran briket dengan bahan baku limbah plastik LDPE dan tempurung kelapa dari kampung nelayan kabupaten cilacap selatan 2) Pengaruh briket terhadap karakteristik briket yaitu kadar air, kadar abu, kadar zat mudah menguap (volatile matter), kadar karbon terikat (fixed carbon), lama nyala api dan nilai kalor. Tempurung kelapa yang digunakan di pirolisis terlebih dahulu pada suhu 500ºC. Briket dicetak dengan menggunakan perekat tapioka sebanyak 5 % lalu dikeringkan pada temperatur 105ºC selama 4 jam menggunakan oven. Briket terbaik diperoleh pada komposisi pencampuran 75% tempurung kelapa dan 25 % plastik LDPE dengan menghasilkan nilai kalor 7.577 kalori/gram, kadar air 5,417 %, kadar abu 2,55 %, volatil matter 38,39 %, dan Fixed carbon 54,67 %. Briket terbaik yang dihasilkan telah memenuhi standar briket PERMEN ESDM no. 47 Th. 2006 
Kata Kunci: briket, plastik LDPE, tempurung kelapa 
 
 
 
 
 
 
 
Abstract 
Production of plastic waste in Indonesia amounted to 5.4 million tons per year , based on the statistical data Indonesia Period Domestic waste plastic waste in the amount of 14 % is the amount of waste production in Indonesia .Mixing waste plastic LDPE with coconut shell which is known to have a high calorific value and the content of volatile matter is quite low rated very potential to be alternative energy sources, namely briquettes. The purpose of this study were 1) Determine the influence of the percentage of briquettes blending with LDPE plastic waste materials and coconut shell from a fishing village south cilacap district 2) The influence of briquettes on the characteristics are water content, ash content, volatile matter content , the levels of carbon bonded (fixed carbon), the old flame and calorific value. Coconut shell used in the first pyrolysis at temperatures of 500ºC. Briquettes are printed using adhesives tapioka as much as 5% and then dried at 100ºC for 4 hours using an oven. Best briquette obtained on the mix composition of 75% and 25% coconut shell by producing LDPE plastic calorific value of 7577 calories / gram, 5.417% moisture content, ash content of 2.55%, volatile matter 38.39%, and 54.67% Fixed carbon , Best produced briquette fulfill the briquettes standards PERMEN ESDM no. 47 Th. 2006 
Keywords: briquettes, LDPE plastic, coconut shells