Types and Applications of Filter Membranes

The membrane filter is widely used in today’s life, including ultrafiltration membrane, microporous membrane, nanofiltration membrane, microfiltration membrane, mesopore fiber ultrafiltration membrane, etc.

Working Principle

Known as surface filtration, membrane filtration is a process that the solid particles can be separated through a very thin filter medium. The particles are usually larger than the pore size of the membrane.

During separation, a semi-permeable membrane acts as a selective barrier retaining the particles bigger than the pore size, as the smaller molecules go through the pores. Removing all micro-organisms and particles reliably, without any effects on the ingredients during the whole process.

Types of Filter Membrane

In terms of shape, filter membranes are usually divided into two types: disc membranes and roll membranes.

Roll filter membrane

Hawach can supply a variety of raw materials for different materials to meet and adapt to the differentiated needs of production membrane manufacturers. The rolling membrane is rectangularly rolled together and is indicated by the width, with 254mm, 260mm, 270mm, 280mm, and 310 mm available. The inner core is 22mm.

Disc filter membrane

The disc membrane filter that HAWACH can provide diameter is 13mm to 293mm, the hole diameter is 0.1μm to 10μm, etc., and other specifications of the membrane can be customized according to the needs of users.

Material of filter membrane

Filter membrane materials include nylon, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), mixed cellulose (MCE), cellulose acetate (CA), glass fiber (GF), Polypropylene (PP), polyethersulfone (PES).

Its application includes HPLC sample preparation, routine QC analysis, protein deposit movement, dissolution test, food analysis, biofuel analysis, and environmental test. We choose some of them for a detailed introduction. For all membrane features and performance, please contact Hawach directly(email: membrane@hawach.com or tel: +86-29-89284429).

Features

1. High porosity: High porosity allows air and liquid to provide high filtration rates in each zone. High porosity also provides a large surface area for adsorption and binding.
2. Diversity: There are many different types of filter membranes, and you can easily find the products you need in our various membranes.
3. High purity: All membranes are produced with high purity raw materials and auxiliaries.
4. High strength: Our membranes have been tested for both rupture and tensile strength. Polytetrafluoroethylene membranes and nylon membranes have strong chemical resistance.
5. Heat resistance: It has excellent heat resistance and low-temperature resistance.
6. Suitability: There is a low coefficient of friction.
7. Moisture resistance: the surface is not wet with water and oil, so it is not easy to dip the solution during operations.
8. Wear resistance: under high load, it has excellent wear resistance.
9. Corrosion resistance: it can protect parts from any kind of chemical corrosion.

Applications

The membrane filter is used for food, beverage, medical medicine, municipal water treatment, industrial high pure water, boiler water, seawater desalination, electronic industry ultra-pure water, wastewater treatment and reuse, material concentration and purification, and other industries.

PP

The PP filter membrane has acid and alkali resistance, abrasion resistance, impact resistance, uniform micropore distribution, large filtration area, and good water permeability. Widely used in injection cleaning, medicinal liquid, medicinal wine, oral liquid, beverage, daily water, wastewater, air filtration, etc.

Glass Fiber(GF)

Due to the fiber material of the glass fiber membrane, it is not easy to clog, so it can provide excellent prefiltration functions for a series of filtration workflows. From basic liquid filtration to highly specialized gas and air filtration, it’s all covered. These properties also make it excellent as a direct filter for a buffer, reagent, and protein solution clarification, as well as for gravimetric analysis, air monitoring, and wastewater analysis. The 100% borosilicate structure of the glass fiber membrane not only gives it a pure white appearance but compared with standard cellulose membranes, even with continuous use, there will be no performance degradation due to increased filtration load.

Cellulose Acetate(CA)

Cellulose acetate(CA) the membrane is mainly used for daily air pollution monitoring and special monitoring of solid pollutants, microorganisms, oil and acid mist in the air, efficient collection of fine particles, and water pollution analysis. It is an ideal product for collecting smoke and dust in the air and measuring it accurately. And it is used for the pre-filtration of the membrane to prevent the clogging of the membrane. Large surface area uses glass fiber membranes for excellent retention.

Polyethersulfone(PES)

In addition to the wide range of applications in the pharmaceutical and biotechnology industries, PES membranes are also suitable for other fields such as medical, food and beverage and drinking water, microelectronics, fine chemicals, etc.

Nylon

The nylon filter membrane material is aliphatic nylon, which has good hydrophilicity and resistance to acid and alkali of the appropriate concentration. It is not only suitable for aqueous solutions containing acid and alkali, but also for organic solvents, such as alcohols, hydrocarbons, ethers, esters, ketones, homologs of benzene and benzene, dimethyl formamide, dimethyl sulfoxide, etc., are one of the most widely applicable microporous membranes. (Belonging to the terminal filter membrane).

Polyvinylidene fluoride(PVDF)

For the PVDF filter, as the pore size of the membrane continues to decrease, the membrane binds to low molecular weight proteins more firmly. The use of the PVDF membrane requires pretreatment. The purpose of treatment with methanol is to activate the positively charged groups on the membrane and make it easier to bind to negatively charged proteins.

Nitro Cellulose

NC membranes are used in Northern Blot, Southern Blot, and Western Blot. Hybridization techniques are divided into solid phase hybridization and liquid phase hybridization. The solid-phase hybridization technology is currently more commonly used. The nucleic acid to be tested is first bound to certain solid-phase support, and then hybridized with the labeled probe in the liquid phase. The solid support is usually the nitrocellulose membrane.

Mixed Cellulose Esters(MCE)

The MCE filter membrane has relatively uniform pore size, high porosity, no media shedding, thin texture, low resistance, fast filtration speed, minimal adsorption, and low cost, but it is not resistant to strong acid & alkali solutions and organic solutions.

Polytetrafluoroethylene(PTFE)

The PTFE filter membrane is made of PTFE, through a special process, two-way stretching, using the unique node fibril properties of the PTFE film, smooth surface, chemical resistance, air and water impermeability, large air permeability, flame retardant, high temperature resistance. The product is resistant to strong acids and alkali, non-toxic, etc., with high filtration efficiency, up to 99.99%, near zero emission; low running resistance, fast filtration speed; long service life, and reusable, thereby reducing operating costs.

Hydrophilic PTFE

Hydrophilic PTFE filter membrane has wide applications, like the flue gas filtration of various industrial furnaces, for instance, the chemical industry, metallurgy,  power generation, cement, etc.

Hawach filter membranes have two types: round disc membrane filters and roll type ones. They can be used for filtration and sterilization of liquids, gas, and other samples.

Summary of the Filter Membrane