[Produksi biogas menggunakan limbah cair kelapa sawit (LCKS) dengan prosesdigesting anaerob menggunakan tangki digester menghasilkan CH4 sebesar ±87% dangas CO2 sebsar ±13%. Metode absorpsi dan kolom adsorpsi adalah beberapa prosessederhana yang mudah untuk diaplikasikan, aplikasinya dapat menggunakan zeolitalam sebagai adsorben dan larutan Ca(OH)2 sebagai absorben. Kedua metode tersebutdapat digunakan secara simultan untuk proses purifikasi biogas dengan cara biogasdialirkan terlebih dahulu ke dalam larutan Ca(OH)2 dan kemudian akan dilewatkan kedalam kolom dengan ukuran tinggi dan diameter dalam sebesar 15cm dan 0,8cm yangberisi zeolit alam termodifikasi. Untuk meningkatkan daya adsorpsi dapat dilakukanmodifikasi permukaan zeolit alam dengan perlakuan asam kuat-basa kuat denganvariasi konsentrasi 1, 2, dan 3M, kalsinasi pada suhu 450°C, dan melapisi permukaanzeolit alam dengan beberapa variasi konsentrasi kitosan yaitu 0,25; 0,5; dan 1%.Penggunaan asam kuat-basa kuat dapat meningkatlkan luas permukaan dan diameter,sedangkan pelapisan kitosan dapat meningkatkan kapasitas adsorpsi pada zeolit alamkarena adanya gugus amine pada kitosan. Hasil modifikasi dan aktivasi zeolit akandiuji menggunakan SEM-EDX, BET, FTIR, dan XRD, sedangkan hasil purifikasibiogas akan diuji menggunakan gas chromatography (GC). Adsorben terbaik yangdidapatkan dari penelitian ini adalah adsorben dengan perlakuan asam-basa 2M yangkemudian dilapisi kitosan 0,5%. Hasil purifikasi yang didapatkan adalah pengurangankadar CO2 pada biogas menjadi 0.42% dan peningkatan kadar CH4 menjadi 99.58%.;Production of biogas from POME by anaerobic digestion process using digester has been shown able to produce CH4 87 and CO2 13 The methods of absorption and adsorption is simple to be applied this method can be done with zeolite as adsorbent and Ca OH 2 as absorbent Both methods can be applied simultaneous for purification which the gas will pass through the chamber Ca OH 2 solution and then passed the column filled with modified natural zeolite Enhancing the adsorption capability done with modified the zeolite using some concentration in strong acid base 1 2 and 3M calcination at 450 C and coating with chitosan 0 25 0 5 and 1 Usage of strong acid and strong base can increase the surface area and diameter of the zeolite pores while coating with chitosan can increase the adsorption capacity because the amine functional group from chitosan The result of the modification of zeolite will be tested with SEM EDX BET FTIR and XRD while the result of the purification will be characterized with GC The best adsorbent from this research is zeolite modified with acid base 2M and coated with 0 5 of chitosan The final result from this research is CO2 about 0 42 and the CH4 become 99 58 , Production of biogas from POME by anaerobic digestion process using digester has been shown able to produce CH4 87 and CO2 13 The methods of absorption and adsorption is simple to be applied this method can be done with zeolite as adsorbent and Ca OH 2 as absorbent Both methods can be applied simultaneous for purification which the gas will pass through the chamber Ca OH 2 solution and then passed the column filled with modified natural zeolite Enhancing the adsorption capability done with modified the zeolite using some concentration in strong acid base 1 2 and 3M calcination at 450 C and coating with chitosan 0 25 0 5 and 1 Usage of strong acid and strong base can increase the surface area and diameter of the zeolite pores while coating with chitosan can increase the adsorption capacity because the amine functional group from chitosan The result of the modification of zeolite will be tested with SEM EDX BET FTIR and XRD while the result of the purification will be characterized with GC The best adsorbent from this research is zeolite modified with acid base 2M and coated with 0 5 of chitosan The final result from this research is CO2 about 0 42 and the CH4 become 99 58 ]