Difference Between Filtration and Centrifugation

Key Difference – Filtration vs Centrifugation

在进行对过滤和离心之间的差异（两种分离技术）之间的差异进行深入分析之前，首先让我们看看是什么分离技术。在生物科学和工程学中，使用一种分离技术来将所需的成分与混合物分离。这是一种传质现象，可将成分的混合物转换为两个或更多不同的分数。混合物的分离取决于混合物组成部分中化学性质或物理特性的差异，例如质量，密度，大小，形状或化学亲和力。分离技术通常根据它们用于实现分离的特定差异进行分类。过滤和离心是仅基于所需颗粒的物理运动的常用分离技术。这key differencebetween过滤和离心在利用力和方法中。过滤通常使用筛分技术在重力的帮助下应对/清除污染物或不希望的材料。This can be achieved through physical barriers such as media, membranes, or strainers.离心利用离心力根据molecular weight。离心机用于此分离。较密集的化合物转移到离心机外部，可以从那里去除。在本文中，让我们详细介绍过滤和离心之间的差异。

什么是过滤？

Filtration is used to separate desiredparticlesor constituents in a mixture orsuspension。根据应用程序，可以使用过滤技术隔离一个或多个感兴趣的组件。这是物理分离方法and it is very important in chemistry, food science, and engineering to separate materials of different chemical composition or to purify化合物。在过滤过程中，分离发生在单个或多个穿孔层/s。在过滤时，保留了太大而无法穿过穿孔层的孔的颗粒。然后，大颗粒可能会在滤波器顶部形成残留物或蛋糕层，也可能阻止滤网，从而防止流体相越过过滤器。

什么是离心？

离心是一个过程centrifuge machine is used to separate desired constituents of a complex liquid mixture/slurry。As a result of centrifugation, the precipitate is more rapidly and completely gathered on the bottom of the centrifuge tube. The remaining liquid is known as the supernatant liquid. This supernatant is then either rapidly transferred from the tube without disturbing theprecipitate,or removed using a Pasteur pipette. The particles precipitating in centrifugation depend on centrifugal acceleration, particles’ size and shape, the volume portion of solids present, the density difference between the particle and the fluid, and theviscosity.

过滤和离心之间有什么区别？

Definition of Filtration and Centrifugation

Filtration:从液体中取出不需要的东西的行为或过程。

离心：分离溶液或混合物的较轻部分的过程。

Characteristics ofFiltration and Centrifugation

过滤和离心可能具有显着不同的特征，可以将其分类为以下亚组。

Force Used

Filtration:这地心引力is used in filtration.

离心：这离心力is used in centrifugation.

Equipment

Filtration:Sieves or perforated layer or strainer or media or physical membrane or filter funnel or their combinations can be used. Some filter aids can be used to help filtration. These are commonly incompressible diatomaceous earth or silica.

离心：使用离心机和离心管。

Method of Operation

Filtration:Large particles in the mixture cannot pass through the mesh/perforated structure of the filter while fluid and small particles pass under the force of gravity becoming filtrate (Figure 1)

离心：将溶液混合物离心，以将较重/浓密的固体迫使底部，在那里经常产生坚固的蛋糕，可以去除或倒入该蛋糕上方的液体。该方法对于分离不滤光的固体特别有用（例如：凝胶状或细颗粒）。（图2）

类型

Filtration:有three filtration techniques基于滑稽可笑的ipated outcome known as hot, cold and vacuum filtration.Hot filtration技术主要用于将固体与热溶液分开。为了避免与溶液接触的滤波器漏斗中的晶体开发。Cold filtrationtechnique is primarily used to rapidly cool the solution to be crystallized. This method results in the development of very small crystals as oppose to getting big crystals by cooling the solution slowly to a room temperature.Vacuum filtrationmethod is primarily used for a small batch of the solution to quickly dry out small crystals. This is the most efficient filtration technique compared to hot and cool filtration.

离心：有三个离心技术即微中心，高速离心机和超中心离心。Microcentrifugeis often used in research activities to process small volumes of biological molecules. This machine is small enough to fix on a table-top.High-speed centrifuges可以处理较大的样品量，主要用于大规模行业应用。Ultra-centrifugationis mainly used for research purposes such as studying properties of biological particles. It is the most efficient separation method compared to micro-centrifuges and high-speed centrifuges.

Purpose

Filtration:过滤的主要目的是通过从混合物中去除杂质或从混合物中分离固体来获得所需的结果。

离心：Main purpose of centrifugation is the isolation of solids from a solution.

效率

Filtration:简单的过滤技术可能需要大量时间来分离所需的材料，因此，过滤效率不如离心效率。

离心：与过滤技术相比，分离发生非常快。因此，离心比过滤更有效。

缺点

Filtration:If very small amounts of solution are filtered, most of this solution may be absorbed by the filter medium. Mixtures containing gelatinous or fine particles do not filter well. Therefore, to separate these mixtures centrifugation can be used.

离心：This method requires know-how and electricity compared to filtration techniques.

成本

Filtration:成本取决于过滤p的复杂性rocess, and usually simple filtration techniques do not require electricity as well as trained persons. Therefore, the associated cost may be low compared to centrifugation.

离心：与简单的过滤技术相比，成本很高，因为离心机需要电力和训练有素的技术人员。

Applications

Filtration:Coffee filter, water filter, furnaces filter to remove particles, Pneumatic conveying systems use filters, in the laboratory, a glass funnel, a Buchner funnel or sintered glass funnel is used for filtration. In the human kidney, renal filtration is used to filter blood and selective re-absorption of many elements vital for the body to maintain homeostasis.

离心：One of the most常见应用is the treatment of sewage sludge where the separation of solid from highly concentrated suspensions. Centrifugation is also used for uranium enrichment process. In addition to that, this technique is used in biological research for isolation of desired solid or liquid from a mixture. In addition, centrifugation is used to remove fat from milk to produce skimmed milk, to clarify and stabilize the wine and to separate of urine constituents and blood elements in forensic and medical research laboratories.

In conclusion, filtration and centrifugation are different separation techniques and the key difference between them is the utilized force and separation equipment. As a result, they may have substantially different applications.

References:

Harrison, Roger G., Todd, Paul, Rudge, Scott R. and Petrides D.P. Bioseparations Science and Engineering. Oxford University Press, 2003.

Cao，W。和Demeler B.（2008）。使用适应性时空有限元元素解决方案进行分析超速离心实验，用于多组分反应系统。Biophysical Journal,(95), 54–65.