<![CDATA[The experiment of surfactant usage in biodeinking process for sorted white ledge (SWL) has been done. Biodeinking processes were carried out in waterbath shaker up to 20 SR and 26 SR freeness at consistency of 25% temperature of 50 ± 5oC, pH 6,5 – 7,0, for 2 hours and 3 hours reaction time. Cellulase addition was varied at 0-0,6% at a constant surfactant of 1,0%. The flotation stage was carried out for 20 minutes at a consistency of 0,8% temperature of 50 ± 5oC and the dosage of collector was 0,08%. The stock was then washed until neutral pH and creened in sommerville screen (150emsh) to remove a small ink particles that was still retained on the treated stock fiber. Handsheets of 60 g/m² made from biodeinking pulp were then tested for dirt count, brightness, tensile index and tear index. The test result showed that the use of SWL- biodeinking pulp up to 30% met the requitment of apacity and water absorption (Cobb). The handsheets caliper still did not meet the satndard yet. The handsheets brightness were lower than standard since the brightness of LBKP used was also low. Although the pH of handsheets were neutral/slighty alkaline (7,0 -7,2), it still did not meet the requirement, i.e. 7.5-8.5.Keywords: waste paper, sorted white ledge(SWL), biodeinking, combined enzyme-surfactant deinking, printing paper propertiesINTISARITelah dilakukan Percobaan penggunaan surfaktan pada proses biodeinking untuk mengolah sorted white ledger (SWL) dengan dua target freeness yakni: 20 dan 26 SR. Reaksi enzim dilakukan di dalam waterbath-shaker pada konsistensi 25% suhu konstant 50 ± 5oC, pH 6,5 - 7,0,dengan waktu reaksi divariasikan: 2 jam dan 3 jam waktu reaksi. Selain selulase bervariasi di 0-0,6% pada surfaktan konstan 1,0%. Tahap flotasi dilakukan selama 20 menit pada konsistensi 0,8% dan suhu 50 ± 5oC. Pada tahap ini ditambah kolektor sebanyak 0,08% terhadap berat kering serat. Stok hasil flotasi disaring menggunakan penyaring Sommervillen (150 menit) untuk menghilangkan sisa partikel tinta kecil yang masih tertinggal dalam serat. Pulp hasil biodeinking dibuat lembaran tangan (60g/m²) dan dievaluasi sifat optik, noda, dan fisik/ekkuatannya. Hasil pengujian lembaran menunjukkan bahwa penambahan pulp SWL hasil biodeinking mkasimum 30% masih dapat memenuhi persyaratan kualitas kertas cetak ditinjau dari opasitas dan daya serap air (Cobb). Tebal lembaran masih belum memenuhi persyaratan.derajat putih LBKP yang rendah yang menjadi penyebabnya. Meskipun pH lembaran sudah ada pada posisi netral / sedikit alkali (7,0 -7,2), itu masih tidak memenuhi persyaratan, yaitu 7,5-8,5.Kata kunci: kertas bekas, Sorted White Ledger (SWL), biodeinking, deinking kombinasi enzim-surfaktan, sifat kertas cetak]]>
