{"id":7752,"date":"2024-03-15T15:00:12","date_gmt":"2024-03-15T15:00:12","guid":{"rendered":"https:\/\/vipur.at\/?p=7752"},"modified":"2024-03-15T15:05:52","modified_gmt":"2024-03-15T15:05:52","slug":"membrane-filter-2","status":"publish","type":"post","link":"https:\/\/vipur.at\/en\/membranfiltertypen\/","title":{"rendered":"Which type of membrane filter do you need?"},"content":{"rendered":"<p class=\"p1\"><span class=\"s1\"><b>Here is our vipur tip for the first important distinguishing feature when choosing a membrane filter:<\/b><\/span><\/p>\n<h2 class=\"translation-block\">Hydrophilic versus Hydrophobic Membrane<\/h2>\n<p class=\"p1\"><span class=\"s1\">You want to filter something with a membrane - but don't quite know which membrane you should use to achieve the desired results? In addition, each membrane has its own special properties, hence our tip for you:<\/span><\/p>\n<p class=\"p1\" style=\"margin-bottom: 0em;\"><span class=\"s1\">The first important question is:<\/span><\/p>\n<h3 class=\"p1\" style=\"margin-top: 0.2em;\"><span class=\"s1\"><b>What do you need to filter - liquid or gas media?<span class=\"Apple-converted-space\">\u00a0<\/span><\/b><\/span><\/h3>\n<p class=\"p1\"><span class=\"s1\">There are two main types of membrane:<\/span><\/p>\n<ul>\n<li class=\"p1\"><span class=\"s1\">hydrophilic membranes \u2192 filtration of liquid substances<\/span><\/li>\n<\/ul>\n<ul class=\"ul1\">\n<li class=\"li1\"><span class=\"s1\">hydrophobic membranes \u2192 filtration of gas substances<\/span><\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p class=\"p1\" style=\"margin-bottom: 0em;\"><span class=\"s1\">What is there to say about them in brief?<\/span><\/p>\n<h3 style=\"margin-top: 0.2em;\"><span class=\"s1\"><b>Hydrophilic membranes<\/b><\/span><\/h3>\n<p class=\"p1\"><span class=\"s1\"><b>Hydrophilic membranes<\/b><\/span><span class=\"s2\"> are \u201cmore or less easily\u201d permeable to water and, as already mentioned, are therefore used for liquid filtration.<span class=\"Apple-converted-space\"><br \/>\n<\/span><\/span><span class=\"s2\">Their structure usually differs depending on the material. The most common at present are:<span class=\"Apple-converted-space\">\u00a0<\/span><\/span><\/p>\n<ul class=\"ul1\">\n<li class=\"li1\"><span class=\"s2\">Polyethersulfone membranes (PES)<\/span><\/li>\n<li class=\"li2\"><span class=\"s2\">Polyvinylidene fluoride membranes (PVDF)<\/span><\/li>\n<\/ul>\n<p class=\"p3\" style=\"margin-top: 1.2em;\"><span class=\"s2\">Depending on the pore size, they are used for bioburden reduction through to virus filtration.<\/span><\/p>\n<p>&nbsp;<\/p>\n<h3><span class=\"s1\"><b>Hydrophobic membranes<\/b><\/span><\/h3>\n<p class=\"p1\"><span class=\"s1\"><b>Hydrophobic membranes<\/b><\/span><span class=\"s2\"> are generally impermeable to water. As a rule, because there are of course various exceptions here too. Normally, PTFE membrane filters are mainly used for sterile gas filtration.<\/span><\/p>\n<ul class=\"ul1\">\n<li class=\"li1\"><span class=\"s2\">Polytetrafluoroethylene membranes (PTFE)<br \/>\n<\/span><br \/>\nThey are characterized by high strength and high chemical compatibility. In practice, this means that PTFE membrane filters can be used for three-digit steam sterilization cycles with up to 145\u00b0C\/30min in the direction of flow and against the direction of flow. By reducing the surface tension, these membranes become hydrophilic and can be used, for example, for the sterile filtration of aggressive liquids.<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p class=\"p2\" style=\"text-decoration: underline;\"><span class=\"s1\">Here is an important note:<\/span><\/p>\n<p class=\"p1\"><span class=\"s1\"><b>Please note that wetting of the hydrophobic membrane with liquid must be prevented.<\/b><\/span><\/p>\n<p class=\"p1\" style=\"text-decoration: underline;\"><span class=\"s1\">What are the most common sources of error\/possible problems?<br \/>\n<\/span><\/p>\n<p class=\"p1\"><span class=\"s1\">Since many PTFE sterile air filters are used for fermenter supply and exhaust air, the formation of condensate and\/or foaming of the fermentation medium is a given.<span class=\"Apple-converted-space\">\u00a0<\/span><\/span><\/p>\n<p class=\"p1\" style=\"text-decoration: underline;\"><span class=\"s1\">Possible solutions:<\/span><\/p>\n<ul class=\"ul1\">\n<li class=\"li1\"><span class=\"s1\">In the event of condensate formation (= wetting of the hydrophobic PTFE membrane with liquid), the use of a filter housing heater is a relatively simple solution.<span class=\"Apple-converted-space\">\u00a0<\/span><\/span><\/li>\n<li class=\"li1\"><span class=\"s1\">If the fermenter frequently foams over, causing the hydrophobic PTFE membrane to block, a polypropylene pre-filter may be a solution.<span class=\"Apple-converted-space\">\u00a0<\/span><\/span><\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p class=\"p1\"><span class=\"s1\">Another membrane type would be hydrophobic PVDF. However, this is only used peripherally due to the limited supply and, above all, the lower air flow rates.<\/span><\/p>\n<p class=\"p1\"><span class=\"s1\">Hydrophilic or hydrophobic membranes - the difference is as simple as that, but there are certain points to consider when using them.<span class=\"Apple-converted-space\"><br \/>\n<\/span><\/span><\/p>\n<p class=\"p1\"><span class=\"s1\">We are happy to provide you with this information for <a href=\"https:\/\/vipur.at\/wp-content\/uploads\/2024\/03\/Dok_vipur_Hydrophilic-vs-Hydrophobic-Membrane_en_2024_03.pdf\" target=\"_blank\" rel=\"noopener\">download<\/a> on our website.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p class=\"p1\"><span class=\"s1\">See you next time - we look forward to further filtration.<\/span><\/p>\n<p class=\"p1 translation-block\">Have a nice day,<br>\nthe vipur Team<\/p>","protected":false},"excerpt":{"rendered":"<p>Hier unser vipur-Tipp f\u00fcr das erste wichtige Unterscheidungsmerkmal bei der Wahl eines Membranfilters: Hydrophile versus Hydrophobe Membrane Sie m\u00f6chten etwas membranfiltrieren \u2013 wissen aber nicht ganz so recht, welche Membrane Sie verwenden sollen, um die gew\u00fcnschten Ergebnisse zu erzielen? Hinzu kommt, dass jede Membrane seine besonderen Eigenschaften hat, daher unser Tipp f\u00fcr Sie: Die erste [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":7125,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"%%post_title%%","_seopress_titles_desc":"Sie m\u00fcssen fl\u00fcssige oder gasf\u00f6rmige Medien filtrieren. Hydrophile vs Hydrophobe Membranen: Unser\r\nvipur Blog zu Membranfiltertypen wie PES \u2714 PVDF \u2714 PTFE \u2714","_seopress_robots_index":"","footnotes":""},"categories":[17],"tags":[],"class_list":["post-7752","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wissenswertes"],"_links":{"self":[{"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/posts\/7752","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/comments?post=7752"}],"version-history":[{"count":1,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/posts\/7752\/revisions"}],"predecessor-version":[{"id":7753,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/posts\/7752\/revisions\/7753"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/media\/7125"}],"wp:attachment":[{"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/media?parent=7752"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/categories?post=7752"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vipur.at\/en\/wp-json\/wp\/v2\/tags?post=7752"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}