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"The development of chiral liquid chromatography, facilitating the straightforward separation of enantiomers, was a significant advance in chromatography, leading to widespread application in analytical chemistry. Application in preparative chromatography has been less rapid, but with the development of single enantiomer pharmaceuticals its use is increasingly common in chemical synthesis at laboratory, pilot plant and even full production scale. This work: brings non-experts up to speed quickly and comprehensively, facilitating the rapid development of effective separations of enantiomeric mixtures on a range of process scales, and presents case studies drawn from within the pharmaceutical industry to clearly illustrate the utility and value of preparative scale enantioselective chromatography in chemical research, development and production."

"Kebutuhan akan enzim papain belakangan ini mengalami peningkatan, dengan laju permintaan sebesar 3 – 5 % pertahun. Proses pemisahan enzim papain dari buah pepaya dengan metode ekstraksi padat – cair (leaching) mempergunakan pelarut air dan campuran buffer dalam prosesnya, dalam experimen digunakan berbagai macam variabel operasi untuk mendukung proses ekstraksi ini berjalan dengan maksimal, seperti variasi suhu dan lama waktu pengadukan (345 rpm). Hasil ekstraksi yang diperoleh kemudian di analisa dengan metode tirosin untuk aktivitas enzim dan metode lowry untuk analisa kadar protein, yang kemudian akan digunakan untuk menghitung berapa aktivitas spesifik tertinggi yang akan diperoleh berdasarkan variasi suhu dan waktu pengadukan. Berdasarkan hasil penelitian diperoleh nilai aktivitas enzim tertinggi pada perlakuan suhu 70˚C dan waktu pengadukan selama 120 menit sebesar 4,68 EU/mL. Sedangkan untuk aktivitas spesifik enzim sebesar 10.34 EU/mg.

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The need for the enzyme papain is greatly increased, its about 3 – 4% /years. The Separation Process of Papain Enzyme from Papaya Fruit by Solid-Liquid Extraction or leaching by using water and solvent mixtures buffer, this process is used in a wide range of operating conditions to support the extraction process such as temperature variations and long stirring.

The results obtained from the extraction are then determine for the enzyme activity by tyrosin method and protein levels by lowry method, and then calculate how the highest specific activity will be retrieved based on variation of temperature and time of stirring.

Based on the research results obtained the value of the highest enzyme activity on the treatment temperature 70˚C and time under stirring for 120 minutes of 4,68 EU/mL. As for the specific enzyme activity of 10.34 EU/mg"

"Dengan permintaan hidrogen yang tinggi di masa depan, pemanfaatan energi dingin tampaknya menjadi solusi alternatif untuk meningkatkan rantai ekonomi hidrogen dengan memaksimalkan pemanfaatan limbah energi dingin selama regasifikasi. Suhu rendah hidrogen cair (-253℃ pada 1 atm) akan memberikan beragam aplikasi yang dapat diimplementasikan. Makalah ini mengusulkan pembangkit daya dan unit pemisahan udara sebagai proses integrasi dari regasifikasi hidrogen cair. Untuk mencapai desain proses terbaik, pemilihan proses dibuat dengan mempertimbangkan tingginya pembangkitan daya dan rendahnya kerusakan eksergi. Desain proses terpilih akan diintegrasikan dengan unit pemisahan udara dengan 4 skenario laju alir dan dioptimasi untuk mendapatkan kondisi ideal dengan maksimal energi listrik hasil dan kerusakan eksergi yang minimum. Solusi ideal setiap scenario akan dievaluasi keekonomiannya. Dari hasil pemilihan proses, cascade rankine cycle mampu memulihkan energi pencairan hidrogen hingga 11,46 % dan menghasilkan kerusakan eksergi yang paling minim. Cascade rankine cycle kemudian diintegrasikan dengan unit pemisahan udara dan dioptimasi. Dari hasil simulasi, semakin tinggi laju alir udara akan menghasilkan energi listrik yang semakin rendah tetapi mampu mengurangi kerusakan eksergi hingga 1700 kW. Dari hasil perhitungan, skenario D, dengan laju alir 12000 kg/jam mampu memberikan internal rate of return paling tinggi (23,96%) dan payback period tersingkat 5,14 tahun dibanding dengan skenario lainnya. 

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With the future's high demand for hydrogen, utilizing cold energy appears to be an alternative solution to enhance the hydrogen economic chain by maximizing the use of cold energy waste during regasification. The low temperature of liquid hydrogen (-253℃ at 1 atm) offers various applicable implementations. This paper proposes integrating a power plant and an air separation unit with the liquid hydrogen regasification process. To achieve the optimal process design, the selection process considers both high power generation and low exergy destruction. The chosen process design will be integrated with the air separation unit under four different flow rate scenarios and optimized to obtain ideal conditions, maximizing electrical energy output and minimizing exergy destruction. The economic feasibility of the ideal solution for each scenario will be evaluated. Based on the process selection results, the cascade Rankine cycle can recover up to 11.46% of the hydrogen liquefaction energy and produce the least exergy destruction. The cascade Rankine cycle is then integrated with the air separation unit and optimized. Simulation results indicate that higher air flow rates yield lower electrical energy but can reduce exergy destruction by up to 1700 kW. According to economic calculations, scenario D, with a flow rate of 12,000 kg/hour, provides the highest internal rate of return (23.96%) and the shortest payback period of 5.14 years compared to other scenarios."

"Traditional column chromatography dominates current purification technology, and many of the productivity gains that have been achieved have relied on upscaling such devices. However, this comes with a cost penalty and the pharmaceutical industry has reached the point at which further upscaling becomes economically unsupportable. This book offers a broad-based reassessment of old and new purification methods, incorporating an analysis of innovative new trends in purification. The book has wide coverage of different antibody purification strategies and brings together top-tier experts to address problems in process-scale antibody purification."