Judul: Utilization of Chitosan as a Coagulant for Wastewater Treatment at CV. Bio Chitosan Indonesia
Abstrak: CV. Bio Chitosan Indonesia (BCI) merupakan sebuah perusahaan yang mengolah limbah cangkang udang dan kepiting salju untuk diproses menjadi kitin dan kitosan. Salah satu permasalahan yang dihadapi perusahaan saat ini adalah proses penanganan limbah yang belum optimal, sehingga diperlukan upaya penanganan yang dapat mengatasi permasalahan tersebut agar limbah yang dihasilkan dapat lebih aman untuk dibuang dan memenuhi standar baku mutu yang berlaku. Upaya yang dapat dilakukan adalah dengan memanfaatkan kitosan sebagai koagulan. Penelitian ini dilakukan untuk mengetahui efektivitas kitosan dan rasio terbaik dalam menurunkan parameter mutu limbah cair di CV. Bio Chitosan Indonesia. Alternatif penanganan limbah terbaik dapat dilakukan dengan melarutkan kitosan dengan rasio 0,75% ke dalam limbah asam dari proses demineralisasi. Jenis kitosan yang digunakan untuk penanganan limbah cair adalah jenis kitosan jatuhan, karena berdasarkan hasil analisis ragam (ANOVA) kitosan komersial maupun kitosan jatuhan memiliki efektivitas yang sama dalam menurunkan nilai pH, TSS, COD dan BOD., CV. Bio Chitosan Indonesia (BCI) is a company that processes shrimp and snow crab shells into chitin and chitosan. One of the current challenges faced by the company is the suboptimal handling of waste, necessitating efforts to address this issue to ensure that the waste is safe to dispose of and meets the quality standards. One potential solution is to utilize low grade of chitosan as a coagulant for waste treatment process. This study was aimed to determine the effective concentration of chitosan for reducing wastewater quality parameters at CV. Bio Chitosan Indonesia. The result shows the the best alternative for waste treatment can be achieved by dissolving 0.75% chitosan into the acidic waste from the demineralization process. The type of chitosan used for wastewater treatment is rejected chitosan, as based on analysis of variance (ANOVA), both commercial and rejected chitosan have the same effectiveness in reducing pH, TSS, COD, and BOD.
Keyword: Chitosan, kitosan, coagulant, waste treatment

Judul: The Chitin Production Process from Shell of Crab Legs at CV. Bio Chitosan Indonesia
Abstrak: CV. Bio Chitosan Indonesia merupakan perusahaan yang mengolah cangkang udang dan kepiting salju (snow crab) menjadi kitin dan kitosan yang berkualitas tinggi. Penelitian ini dilakukan untuk menganalisis pengaruh konsentrasi HCl, waktu proses, dan suhu proses demineralisasi pada produksi kitin dari cangkang kaki rajungan di CV. Bio Chitosan Indonesia. Percobaan dilakukan melalui dua tahapan proses produksi kitin pada skala laboratorium menggunakan Rancangan Acak Lengkap Faktorial (RALF) dan Rancangan Acak Lengkap Single Factor (RALSF). Analisis ragam menunjukkan konsentrasi HCl, waktu proses demineralisasi, dan interaksi keduanya tidak berpengaruh nyata terhadap rendemen dan mutu kitin dari cangkang kaki rajungan, namun suhu proses demineralisasi berpengaruh nyata terhadap rendemen dan mutu kitin dari cangkang kaki rajungan. Perlakuan terbaik diperoleh dari kondisi proses produksi kitin dari cangkang kaki rajungan menggunakan larutan HCl 8%, waktu proses 3 jam, dan suhu ruang (30oC) dengan rendemen, kadar air, dan kadar abu masing – masing sebesar 20,44%, 3,36%, 0,33%. Kitin yang diperoleh sudah memenuhi standar mutu yang ditetapkan pembeli CV. Bio Chitosan Indonesia dan SNI., CV. Bio Chitosan Indonesia is a company engaged in processing shrimp and snow crab shells into high-quality chitin and chitosan. This research was conducted to analyze the influence of HCl concentration, process time, and demineralization process temperature on chitin production from shell of crab legs at CV. Bio Chitosan Indonesia. The experiment was carried out in two stages of chitin production at the laboratory scale using a Full Factorial Randomized Complete Design (FFRCD) and a Single Factor Randomized Complete Design (SFRCD). Analysis of variance showed that the concentration of HCl, demineralization process time, and their interaction did not significantly affect the yield and quality of chitin from the shell of crab legs. However, the demineralization process temperature significantly affected the yield and quality of chitin from the shell of crab legs. The best treatment was obtained from the chitin production process conditions from shell of crab legs using an 8% HCl solution, a process time of 3 hours, and room temperature (30°C), resulting in yields, moisture content, and ash content of 20.44%, 3.36%, and 0.33%, respectively. The obtained chitin meets the quality standards set by the buyers of CV. Bio Chitosan Indonesia and SNI.
Keyword: crab leg shell, demineralization, chitin

Judul: Konstruksi Hukum Grup Kurva Eliptik Atas F3m
Abstrak: Elliptic curves upon F3m can be divided in two cases, i.e. supersingular and nonsupersingular case. Based on group laws on elliptic curves, a new arithmetic upon F3m can be formulated as an addition process of two random points on the curve. This addition process can then be applied to the ElGamal algorithm.
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