Kadang kita merasa bahwa kita mencintai seseorang, tapi tanpa kita sadari itu hanya kamuflase. Coba kita renungkan lagi. Apakah yang kita kira cinta itu sebenarnya adalah kita yang tidak ingin sendirian dan kesepian? Apakah yang kita kira cinta itu sebenarnya adalah karena orang itu bisa memupuk ego kita? Apakah yang kita kira cinta itu sebenarnya adalah karena orang itu terlalu baik untuk hidup kita yang kita rasa menyedihkan? Jika jawaban dari semua pertanyaan itu adalah ya, maka cinta yang kita kira ada itu hanyalah cinta kita kepada diri sendiri.

Ketika ada orang yang ingin berteman dengan kita, terimalah. Jangan ditolak. Mungkin kita tidak menyukainya atau tidak suka pada sifatnya, bahkan mungkin buat kita dia tidak berarti. Tapi dengan dia mau berteman dengan kita, artinya dia menyukai kita. Bahkan mungkin buat dia kita berarti. Bukankah menyenangkan disukai orang bahkan dianggap berarti? Jangan terlalu cepat tidak suka pada seseorang tanpa berusaha mengenal lebih jauh, karena itu hanyalah penilaian subyektif kita berdasarkan apa yang mau kita lihat. Mereka yang datang ke dalam hidup kita dikirim langsung oleh Tuhan. Kita tidak pernah tau, mungkin orang itulah yang akan menjadi pengaruh terbesar dalm hidup kita.

Ketika ada teman yang meminta tolong pada kita, bantulah. Jangan ditolak mentah-mentah, apalagi jika memang kita mampu membantunya. Karena bahkan dengan meminta tolong saja dia sudah buang malu. Sekarang ini dia yang meminta tolong pada kita, besok mungkin kita yang akan meminta tolong padanya. ~MYF

Kelebihan dan kekurangan akan sifat seseorang merupakan penilaian subyektif dari sesama manusia berdasarkan apa yang disukai dan tidak. Tapi di mata Tuhan Yang Maha Menciptakan tidak ada sifat ciptaanNya yang lebih maupun kurang, karena semua bersumber dariNya. ~MYF

Dalam hidup kadang kita temukan orang yang terkesan tidak mau meminta tolong pada orang lain dan karenanya kita jadi tidak suka padanya, menilai bahwa dia arogan. Padahal mungkin saja dia bersikap begitu karena dulunya pernah meminta tolong pada temannya dan ditolak mentah-mentah sehingga menimbulkan trauma batin baginya. Jangan terlalu cepat menilai orang hanya dari luarnya saja. Setiap orang punya cerita masa lalu yang tidak kita ketahui. ~MYF

Bahkan perbuatan baik kita sekalipun bisa tidak disukai dan dihargai semua orang. Namun demikian berbahagialah, Tuhan tau niat kita tulus. Tetaplah berbuat kebaikan bahkan sekalipun tidak ada yang menyukai dan menghargai. Selama niat tulus itu selalu mendasari, Tuhan sudah mencatatnya sebagai amal ibadah. ~MYF

Manajemen Limbah Medis

DEFINISI

Sebenarnya tidak ada definisi yang pasti dan universal tentang limbah medis. Oleh sebab itu banyak sekali istilah yang digunakan untuk limbah jenis ini, mulai dari limbah medis, limbah rumah sakit, limbah infeksius, limbah fasilitas kesehatan dan regulated medical waste.

Berdasarkan US-EPA, limbah medis adalah limbah yang dihasilkan dari fasilitas medis: rumah sakit, klinik, praktek dokter/dokter gigi, bank darah, rumahsakit/klinik khusus hewan, lembaga riset medis dan laboratorium medis. Sedangkan menurut Medical Waste Tracking Act 1988, limbah medis adalah semua limbah padat yang dihasilkan dari kegiatan diagnosa, pengobatan atau imunisasi manusia dan hewan; riset medis; dan produksi atau pengujian material biologis.

Karena banyaknya pengertian yang beredar tentang limbah jenis ini, maka untuk lebih memudahkan dilakukan klasifikasi sebagai berikut:

  • Limbah rumah sakit atau limbah fasilitas kesehatan adalah semua limbah, baik biologis maupun non-biologis, yang dibuang oleh suatu fasilitas kesehatan dan tidak ditujukan untuk penggunaan lebih lanjut.
  • Limbah medis adalah material yang ditimbulkan dari hasil kegiatan diagnosa pasien, pengobatan atau pemberian imunisasi kepada manusia atau hewan.
  • Limbah infeksius atau regulated medical waste adalah limbah medis yang dapat menyebarkan wabah infeksi.

Catatan: Kongres Amerika Serikat dan US-EPA menggunakan istilah regulated medical waste untuk limbah infeksius.

CONTOH LIMBAH MEDIS

  • Perban bekas membalut luka/darah
  • Peralatan bekas kultur
  • Sarung tangan bedah bekas pakai
  • Instrumen bedah bekas pakai
  • Jarum suntik bekas pakai
  • Semua peralatan untuk penanaman kultur
  • Organ tubuh sisa pembedahan

BIOHAZARD

Adalah substansi biologis yang mengandung bahaya yang dapat mengancam makhluk hidup terutama manusia. Termasuk di dalamnya antara lain limbah medis, contoh mikroorganisme, virus atau racun yang berasal dari sumber biologis yang berefek pada manusia, serta substansi yang berbahaya bagi hewan.

KLASIFIKASI BIOHAZARD

  • Kategori A, UN2814 – substansi infeksius yang berefek kepada manusia dan hewan. Merupakan substansi infeksius yang dapat menyebabkan disabilitas permanen atau mengancam nyawa atau penyakit fatal pada manusia atau hewan ketika terpapar.
  • Kategori B, UN2900 – substansi infeksius yang hanya berefek kepada hewan. Merupakan substansi infeksius yang tidak dapat menyebabkan disabilitas permanen atau mengancam nyawa ataupenyakit fatal pada manusia atau hewan ketika terpapar.
  • Kategori B, UN3373 – substansi biologis yang digunakan untuk tujuan diagnosa dan investigasi.
  • Regulated Medical Waste, UN3291 – limbah atau material yang dapat digunakan kembali yang dihasilkan dari pengobatan medis terhadap manusia atau hewan, atau dari riset biomedis, termasuk produksi dan pengujian produk biologis.

TINGKATAN BIOHAZARD

  • Tingkat 1 – bakteri dan virus beberapa kultursel dan bakteri non-infeksius. Tindakan pencegahan pada tingkat ini tergolong minimal, hanya meliputi sarung tangan dan pelindung wajah.
  • Tingkat 2 – bakteri dan virus yang menyebabkan penyakit ringan pada manusia, atau yang sulit dimatikan dengan aerosol pada prosedur laboratorium.
  • Tingkat 3 – bakteri dan virus yang dapat menyebabkan penyakit berat dan fatal pada manusia, tetapi sudah ada vaksin atau pengobatannya.
  • Tingkat 4 – bakteri dan virus yang dapat menyebabkan penyakit berat dan fatal pada manusia dan belum adavaksin atau pengobatannya.

REGULASI MANAJEMEN LIMBAH MEDIS DI INDONESIA

  • Undang-undang No.32/2009 tentang Perlindungan dan Pengelolaan Lingkungan Hidup.
  • Peraturan Pemerintah No. 18/1999 tentang Pengelolaan Limbah B3.
  • Peraturan Pemerintah No. 85/1999 tentang Revisi Beberapa Pasal PP 18/1999.
  • Peraturan Menteri Lingkungan Hidup No. 14/2013 tentang Simbol dan Label Limbah B3.
  • Peraturan MenteriKesehatan No. 1204/2004 tentang Persyaratan Kesehatan Lingkungan Rumah Sakit.
  • Keputusan Kepala BAPEDAL Kep-01/BAPEDAL/09/1995 tentang Tata Cara dan Persyaratan Teknis Penyimpanan dan Pengumpulan Limbah B3.
  • Keputusan Kepala BAPEDAL Kep-02/BAPEDAL/09/1995 tentang Dokumen Limbah B3.
  • Keputusan Kepala BAPEDAL Kep-03/BAPEDAL/09/1995 tentang Persyaratan Teknis Pengolahan Limbah B3.

PENGEMASAN

  • Semua limbah medis hanya boleh dibuang menggunakan kemasan khusus berlogo biohazard.
  • Limbah medis tajam seperti jarum, pisau bedah, alat suntik (dengan atau tanpa jarum) dan benda medis lainnya yang dapat menyayat dan menusuk kulit, serta limbah infeksius seperti sisa preparat dan kultur bakteri harus dikemas menggunakan kemasan yang keras, tahan pecah, tahan tusuk, anti bocor dan kedap air.
  • Limbah infekisus seperti kapas, masker dan sarung tangan dapat dibuang menggunakan plastic bag.
  • Batas pengisian maksimal adalah ¾ penuh.

PENGUMPULAN, PENYIMPANAN DAN PENGANGKUTAN

  • Pengumpulan limbah medis harus menggunakan troli tertutup.
  • Pengumpulan limbah medis berupa bendatajam (scalpel, jarum, kaca preparat) dikumpulkan ke dalam suatu wadah khusus tanpa memperhatikan terkontaminasi atau tidaknya.
  • Penyimpanan limbah medis harus sesuai dengan iklim tropis, yaitu paling lama 48 jam pada musim hujan dan 24 jam pada musim kemarau.
  • Pengangkutan limbah medis keluar dari fasilitas medis harus menggunakan kendaraan khusus.

PENGOLAHAN

  • Sterilisasi panas kering dengan menggunakan oven Poupinel pada suhu 160 derajat Celsius selama 120 menit atau pada suhu 170 derajat Celsius selama 60 menit.
  • Sterilisasi panas basah dengan menggunakan autoclave pada suhu 121 derajat Celsius selama 30 menit.
  • Sterilisasi dengan menggunakan bahan kimia berupa gas ethylene oxide pada suhu 50-60 derajat Celsius selama 3-8 jam, atau dengan menggunakan glutaraldehyde selama 30 menit.
  • Disinfeksi
  • Degradasi kimia
  • Insinerasi suhu tinggi
  • Enkapsulasi
  • Inersisasi

Catatan:

  • Bagi fasilitas medis yang memiliki insinerator di lingkungannya harus membakar limbah medisnya selambat-lambatnya 24 jam.
  • Bagi fasilitas medis yang tidak memiliki insinerator di lingkungannya, maka limbah medisnya harus diolah melalui kerjasama dengan fasilitas medis lain atau pihak lain yang memiliki izin pengoperasian insinerator untuk diolah selambat-lambatnya 24 jam jika disimpan pada suhu ruang.

PENGGUNAAN KEMBALI

  • Limbah medis yang akan digunakan kembali harus melalui proses sterilisasi terlebih dahulu. Untuk mengetahui efektivitas sterilisasi panas harus menggunakan tes Bacillus stearothermophillus, sedangkan untuk mengetahui efektivitas sterilisasi bahan kimia harus menggunakan tes Bacillus subtilis.
  • Limbah medis yang dapat digunakan kembali meliputi scalpel, jarum hipodermik, syringe dan botol gelas.

Catatan:

Limbah jarum hipodermik TIDAK dianjurkan untuk digunakan kembali. Apabila fasilitas medis tidak mempunyai jarum sekali pakai, maka limbah jarum hipodermik dapat digunakan kembali setelah melalui sterilisasi.

Treatibility Trial for Stabilization of Dry Flux Waste

Overview:

The aim of this trial was to determine the ratio of stabilization prescription to treat dry flux waste generated from a musical instrument manufacturer which leached out high level of boron, i.e. 1301 ppm; while the limit is only 500 ppm according to the Indonesian environmental regulations. Stabilization is required in response to the regulations which restrict specific categories of waste from hazardous waste landfills unless the wastes are pretreated to a minimum leachibility standard. The intent is to reduce the leachibility of hazardous constituents as measured by the TCLP. Stabilization process is effective in treating a variety of difficult to manage waste materials for reuse or disposal. This method has been identified as the Best Demonstrated Available Technology (BDAT) for treating a wide range of Resource Conservation and Recovery Act (RCRA) non-wastewater hazardous waste categories.

Flux is a chemical cleaning agent, flowing agent or purifying agent. It is usually used in the field of metallurgy in both extractive metallurgy and metal joining (welding, brazing and soldering). In soldering of metals, flux serves a threefold purpose: it removes oxidation from the surfaces to be soldered; it seals out air thus preventing further oxidation; and by facilitating amalgamation improves wetting characteristics of the liquid solder. Common fluxes are: ammonium chloride or rosin, hydrochloric acid, zinc chloride and borax.

Experiment:

Method for Mixing Dry Flux and Pozzolanic

The first step of this trial was by mixing the waste with stabilization reagents. Water was then added for the stabilization reagents to react, performing a cementation reaction. All the mixing was performed by hand. After all the mixing procedures, the waste was then placed into a plastic bottle and was left undisturbed and let to dry. After a period of time, TCLP test was conducted to observe the leaching concentration. In this trial, three stabilization reagents were used, i.e. fly ash, Portland cement and lime.

Measurement of Leaching Concentration

According to the regulation of the State Ministry of Environment – Republic of Indonesia, sulfuric acid pH of 5 was used as the extraction fluid on the TCLP with liquid to solid ratio of 20:1. The sample was extracted for 16-20 hours on an agitation tumbler. The TCLP extract was then separated from the solid phase by filtering through a 0.6 micron filter.

Analysis of Leaching Elements

The leaching concentration of boron was analyzed by ICP-OES method.

Waste Characteristics

The waste to be treated on this case was flux generated from soldering process on a musical instrument manufacturer. The condition of the waste was already cured and attached on the surface of the product. The finger print test results showed that the physical appearance of the waste was broken white homogeneous lumps, odorless, not detected sulfide, cyanide, oxidizer, ammonia and phenol, at/below background level of radioactivity and insoluble in water. The metal on waste analysis results showed that the waste was containing 45190 ppm of boron; while the TCLP test results confirmed that the waste was leaching out 1301 ppm of boron.

Results and Discussion:

Concerning its generating process that was soldering and the physical appearance of the waste that is broken white, flux on this case is suspected to be a mixture of borax and ammonium chloride as is common for soldering. This has been confirmed via both on waste analysis and TCLP test results shown on the Table 2 and Table 3. The high concentrations of boron shown on the TCLP pure waste results were caused by the low pH level. In order to be able to reduce the leaching concentration of this metal, the pH level must be increased to the alkaline condition.

Stabilization with fly ash and Portland cement

A pozzolanic compound composed of fly ash and Portland cement is the common reagents used for stabilization process. A combination of these reagents with ratios of 0.15 of fly ash and 0.10 of Portland cement has been proven in the stabilization of so many hazardous waste. But on this case, this prescription was unable to reduce the leaching concentrations of boron, whereas the desired alkaline condition was not obtained and the concentration of boron remained high even after doubled up the ratio. The results are shown on the following table:

FA Ratio

PC Ratio

pH

Boron (ppm)

0.15

0.10

6.33

1378

0.30

0.20

6.59

1246

Table 1. TCLP stabilized waste results with fly ash and Portland cement

Stabilization with fly ash, Portland cement, lime and filler

From the results presented above, reducing the leaching concentrations of boron simultaneously with only fly ash and Portland cement was seemed to be difficult; therefore led to the consideration of adding other reagents, i.e. lime and filler (sand) on this trial referred to the similar research case on Oji Paper Co. Ltd in Japan at 2006 performed by Makoto Iwasaki, et al, which focused on the leaching of fluorine and boron on coal ash. Lime was selected due to its ability to maintain the alkaline condition, as well as from the economical and general usage point of view. The presence of lime was also expected to form more ettringite during the cement swelling, which has been reported to be effective for reducing the leaching concentration of boron (J.K. Solem-Tishmack et al, 1995). Filler (sand) was used as binder to bind the aggregate particles together, preventing the entrance of moisture. The results are shown on the following table:

FA Ratio

PC Ratio

Lime Ratio

Filler Ratio

pH

Boron (ppm)

0.15

0.10

1.00

0.50

13.00

603.6

0.15

0.10

1.50

0.50

13.52

245.2

Table 2. TCLP stabilized waste results with fly ash, Portland cement, lime and filler

Table 2 clearly shows that the presence of lime in every prescription, combined with the existing ratios of fly ash and Portland cement, was able to reduce the leaching concentration of boron significantly. With the ratios of 0.15 of fly ash, 0.10 of Portland cement, 1.50 of lime and 0.50 of filler, the prescription was able to reduce the concentration of boron on the leaching from 1301 ppm to 245.2 ppm.

This prescription indeed resulted extreme pH levels out of the standard range (i.e. 9-11) which was predicted would be affecting the quality of leachate after the treated waste been disposed to the secure landfill, i.e. causing the significant level of TDS due to the precipitation of metal ions as carbonates and hydroxides. As alternative to encounter the pH level of the treated waste from exceeding the limits, the waste can also be treated by double encapsulation in concrete method followed by disposal into class 1 secured landfill. In this method, the waste will not undergo any chemical reactions but isolated inside a massive solid mass hence will not be migrating to the environment.

Conclusions:

  1. The prescription consisting of fly ash, Portland cement, lime and filler was able to reduce the leaching concentration of boron below the Indonesian environmental standard (i.e. 500 ppm).
  2. The ettringite structure was formed on this prescription, which might be related to the reducing of the leaching concentration of boron.
  3. The optimum ratios were obtained by 0.15 of fly ash, 0.10 of Portland cement, 1.50 of lime and 0.50 of filler.
  4. As alternative the waste can also be treated by double encapsulation in concrete method to encounter the pH level of the treated waste from exceeding the limits.

References:

  1. Chou, S.T. and L.T. Fan, 1995, “Stabilization and Solidification”, Chemical Engineering Department – Kansas State University, Kansas.
  2. Flux (Metallurgy). In Wikipedia. Retrieved August 22, 2013, from http://en.wikipedia.org/wiki/flux_(metallurgy).
  3. Iwasaki, Makoto et al, 2006, “Prevention of Elements Leaching from Coal Ash by Adding Fixation Chemicals”, Research and Development Department – Oji Paper Co. Ltd, Tokyo.
  4. Lear, Paul and Jesse Conner, “Stabilization Reagent Testing”, GenevaResearchCenter – Chemical Waste Management Inc., Illinois.
  5. Republic of Indonesia, 1999, Government Regulations No. 85 Year 1999: Hazardous Waste Management.
  6. Solem-Tishmack, J.K. et al, 1995, “High Calcium Coal Combustion By-products: Engineering Properties, Ettringite Formation and Potential Application in Solidification and Stabilization of Selenium and Boron”, Cement and Concrete Research, 125(3) 658.
  7. US EPA, 1993, “Technical Resource Document: Solidification/Stabilization and its Application to Waste Materials”, Office of Research and Development, Washington, D.C.

Medical and Infectious Waste

Medical waste: any solid waste which is generated in the diagnosis, treatment (e.g. provision of medical services) or immunization of human beings or animals, in research pertaining thereto, or in the production or testing of biologicals (US-EPA).

Infectious agent: any organism (such as virus or bacteria) that is capable of being communicated by invasion or multiplication in body tissues and capable of causing disease or adverse health impacts in humans (US-EPA).

Infectious waste: waste that contains pathogens with sufficient virulence and quantity such that exposure to the wastes could result in infectious diseases.

However, currently there is no definitive quantitative analysis that can be used to determine whether or not a waste is infectious. The characteristic of infectious potential is therefore based on principles of disease transmission. The process of disease transmission can be conceptualize as a series of six links, with each link representing an essential step in the transfer of an infectious agent from one susceptible host to the next. If a break occurs in any of the links along the chain, the process of disease transmission is inhibited. The six links are as follows:

  1. The presence of a sufficient quantity  of an infectious agent.
  2. The existence of a favourable environment for survival of infectious agents.
  3. A mode of escape for infectious agents.
  4. An infectious mode of transmission.
  5. An infectious route of entry.
  6. A susceptible host.

Four main transmission modes of infection (US Department of Health and Human Services):

  1. Direct transmission occurs when there is contact between an agent’s source and susceptible host. Direct transmission can occur through direct contact or droplet spray.
  2. Airborne transmission occurs when the etiologic agent is contained in or on relatively small particles that remain suspended in air for long periods of time.
  3. Vehicle-borne transmission occurs when an infectious agent is transported from its source to a susceptible host by contaminated materials or objects (indirect contact).
  4. Vector-borne transmission occurs when a vector, most commonly insect, carries the agent on or in its body, or the agent develops in the vector.

Types of Medical Waste

The rationale behind the definition of what constitutes medical waste is based on two sets of criteria:

1. The potential of the waste to transmit infection. These wastes, by virtue of their characteristics, are capable of preserving the chain of disease transmission. These wastes are universally handled as medical wastes, regardless of their source, because:

  1. The infectious potential of a waste cannot necessarily be determined by its appearance.
  2. The particular source of the item and/or its infectious nature may not be identifiable.
  3. It is impractical and infeasible to test each item for its pathogen content (i.e. type and quantity).

These types of medical waste fall into seven categories as follows:

  1. Sharps that have been used in animal or human patient care or treatment or in medical, research or industrial laboratories. Includes hypodermic needles, syringes, scalpel blades, blood specimen tubes, pasteur  pipettes and broken glass that have been exposed to infectious agents.
  2. Cultures and stocks of infectious agents and associated biologicals. Includes specimen cultures from medical and pathological laboratories; cultures and stocks of infectious agents from research and industrial laboratories; waste from the production of biologicals; discarded live and attenuated vaccines; and culture dishes and devices used to transfer, inoculate and mix cultures.
  3. Bulk human blood and blood products. Liquid waste human blood, products of blood, items saturated and with the potential for dripping blood, serum, plasma and other blood components.
  4. Pathological wastes. Human tissues, organs, body parts and body fluids that are removed during surgery and post mortem procedures, with the exception of teeth, faeces, excreta and corpses and body parts intended for interment or cremation.
  5. Isolation wastes. Includes wastes contaminated with blood, excretions, exudate or secretions from sources isolated to protect others from highly communicable infectious disease which are identified as viruses.
  6. Animal waste. Contaminated animal carcasses, body parts, fluids and bedding of animals that have been afflicted with suspected zoonotic disease or purposely infected with agents infective to humans during research, in the production of biologicals or the in vivo testing of pharmaceuticals.
  7. Unused sharps. Hypodermic needles, suture needles, syringes, scalpel blades. This category is included because of the risk of the item having been used without the handlers’ knowledge and the added potential for illicit use if these items are disposed as solid waste. In addition, unused sharps have the potential to causing physical injury from improper handling.

2. Wastes which possess a risk to public health or the environment for reasons other than infectious potential. These wastes fall into three additional categories as follows:

  1. Low level radioactive waste. From administering radiopharmaceuticals and performing nuclear medicine procedures and radioimmunology procedures. These wastes, such as radioactive sharps, are not under the regulations of nuclear agency/commission.
  2. Antineoplastic (cytotoxic, cytostatic) drugs. Trace contaminated materials and contaminated human excreta that are not handled as hazardous waste.
  3. Small volume of chemical hazardous waste. These wastes are products of a process or operation involving the use of hazardous chemicals.

Items That Are Not Medical Waste

According to the principles of infectious disease transmission, minimally soiled items in contact with infectious agents are probably not capable of infectious disease transmission because the potentially infectious materials will be contained or confined in the waste materials. If the items become saturated with blood, excretions, exudate or secretions containing a sufficient number of infectious agents, however, they would then be similar to material in the cultures and stocks, bulk human blood and blood products and animal waste categories and capable of infectious disease transmission, provided an appropriate portal of entry is present in a susceptible host (US Department of Health and Human Services).

Generation of Medical Wastes

There are many sources of medical waste with a wide variation in the amount of waste produced by each type of generator. The range of potential generators includes:

  1. Hospitals: general medical and surgical, psychiatric, tuberculosis, other specialty (OB/GYN, eye, ENT, rehabilitation)
  2. Intermediate care facilities: nursing homes, in-patient care facilities for the developmentally disabled
  3. Clinics: chronic dialysis, free clinics, community, employee, surgical, urgent care, abortion, drug rehabilitation, health maintenance organization
  4. Physician offices: general and family practice, internal medicine, paediatrics, OB/GYN, ophthalmology, orthopaedic surgery, general surgery, dermatology, psychiatry, otorhinolaryngology, urological surgery, cardiovascular disease, neurology
  5. Dental offices
  6. Laboratories: medical, research, industrial, commercial diagnostic, biologics manufacturing, medicinal chemicals and botanical products, pharmaceutical preparations
  7. Funeral homes
  8. Veterinarians
  9. Agricultural
  10. Blood banks
  11. Animal care: shelters, fur farms, breeders, experimentation units
  12. Emergency medical services: ambulance service
  13. Hospices
  14. Household/home health care: health care providers, self care
  15. Health units in industry, schools, correctional facilities, fire and rescue services
  16. Medical and nursing schools
  17. Illicit drug users

Ekstraksi Superkritis

Ekstraksi superkiritis merupakan salah satu metode operasi ekstraksi dengan menggunakan solven berupa fluida superkritis, yaitu fluida yang kondisinya berada di atas temperatur dan tekanan kritis. Temperatur kritis adalah suhu tertinggi yang dapat mengubah fase gas suatu zat menjadi fase cair dengan cara menaikkan tekanan. Sedangkan tekanan kritis adalah tekanan tertinggi yang dapat mengubah fase cair suatu zat menjadi fase gas dengan cara menaikkan temperatur. Pada kondisi ini fluida memiliki sifat di antara cairan dan gas. Metode ini memiliki beberapa kelebihan, antara lain:

  1. Kekuatan solven dapat diatur sesuai keperluan dengan mengatur kondisi operasinya.
  2. Daya larut solven tinggi karena bersifat seperti cairan.
  3. Viskositas solven rendah karena bersifat seperti gas, sehingga koefisien perpindahan massanya tinggi.
  4. Pemisahan kembali solven dari ekstrak cukup cepat dan sempurna karena pada keadaan normal solven tersebut berupa gas, sehingga dengan penurunan tekanan solven otomatis akan keluar sebagai gas.
  5. Dapat menggunakan solven berupa fluida yang tidak merusak lingkungan dan tidak mudah terbakar.
  6. Difusi dalam padatan dapat berlangsung cepat.
  7. Temperatur operasi bisa rendah sekalipun tekanannya tinggi.

Salah satu fluida yang sering dipakai sebagai solven dalam ekstraksi superkritis adalah gas CO2, yang memiliki temperatur kritis 31,3 derajat Celcius dan tekanan kritis 74 atm. Dengan menggunakan CO2 sebagai solven, ekstraksi superkritis dapat dijalankan pada suhu rendah dan tekanan yang tidak terlalu tinggi. Keuntungan lain adalah kita tidak perlu membuat CO2 melainkan cukup menyaringnya dari udara sekitar.

Sebagai fluida superkritis, CO2 telah cukup banyak dimanfaatkan di bidang penelitian dan industri. Contohnya adalah dalam proses ekstraksi maupun de-ekstraksi senyawa-senyawa aktif dari tumbuhan untuk pengobatan atau senyawa-senyawa penting untuk industri makanan, misalnya ekstraksi minyak atsiri lemon, jahe, beta-carotene dari tumbuh-tumbuhan atau de-ekstraksi kafein pada kopi.

Follow

Get every new post delivered to your Inbox.

Join 102 other followers