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Qualitative filter paper 18cm slow speed

12.5cm diameter qualitative filter paper

Professional handling of laboratory filter paper

Bulk round laboratory filter paper stock

Texture of laboratory cellulose filter paper

Qualitative vs Quantitative filter paper chart

Qualitative filter paper 18cm medium speed

Qualitative filter paper 18cm fast speed

Qualitative filter paper 15cm slow speed

Qualitative filter paper 15cm medium speed

Qualitative filter paper 15cm fast speed

Qualitative filter paper 12.5cm medium speed

Qualitative filter paper 12.5cm fast speed

Qualitative filter paper 11cm slow speed

Qualitative filter paper 11cm medium speed

Qualitative filter paper 11cm fast speed

Qualitative filter paper 9cm medium speed

Qualitative filter paper 7cm medium speed

Features & Details

🌿 100% ALPHA CELLULOSE	High-purity cotton linters deliver superior wet strength and liquid absorbency without lint shedding.
⏱️ 3 RETENTION SPEEDS	Fast (80-120μm), Medium (30-50μm), and Slow (1-3μm) grades for tailored precipitate separation.
🔥 LOW ASH CONTENT	Controlled ash content (<0.15%) makes these circles ideal for qualitative assays and filtration.
📏 7CM TO 18CM SIZES	Standard circular discs cut cleanly to fit conical funnels and ceramic Buchner funnels snugly.

About this item

Product specification

Parameter

Xin Tester Specification Details

Material & General Specifications

Material

100% Virgin Cotton Fiber (α-cellulose >98%)

Ash Content

< 0.1% (Standard Qualitative Grade)

Max Operating Temp

120 °C (Suitable for hot liquid filtration)

Packaging

100 Sheets per Box

Filtration Speeds & Pore Sizes

Speed Type

Pore Size (µm)

Filtration Time (per 100mL)

Fast

10 – 12 µm

28 – 35 sec

Medium

7 – 8 µm

50 – 60 sec

Slow

3 – 4 µm

80 – 90 sec

Funnel Size Compatibility Guide

7 cm Paper → Fits 40-50mm Funnels

9 cm Paper → Fits 50mm Funnels

11 cm Paper → Fits 60mm Funnels

12.5 cm Paper → Fits 75mm Funnels

15 cm Paper → Fits 90-100mm Funnels

18 cm Paper → Fits 120mm Funnels

Solid-Liquid Gravimetric Clarification & Analysis

Qualitative Filter Paper, 100% Cotton Cellulose Lab Solid-Liquid Separation Circles Professional Series

Ensuring dependable accuracy during daily operations requires professional equipment engineered to withstand demanding laboratory and industrial environments. The Xin Tester Qualitative Filter Paper, 100% Cotton Cellulose Lab Solid-Liquid Separation Circles (100 Pcs) provides verified stability, user-friendly operation, and certified safety compliance across standard maintenance protocols. Discover our complete line of diagnostic and testing instruments in the Lab Consumables catalog.

High Wet-Tensile Strength

Treated to resist pressure tearing during suction or gravity filtration, ensuring that filter cakes remain intact without fiber shedding.

Uniform Pore Matrix

Homogeneous fiber intertwining guarantees steady flow rates while cleanly trapping coarse or gelatinous precipitates.

💡

Filtration Insight: Membrane Selection & Pore Integrity

Selecting the proper polymer membrane prevents dissolution and extractable contamination. 0.22μm grades provide biological sterility, while 0.45μm grades clarify solutions and culture buffers efficiently under negative pressure.

Ordering & Model Verification

Ensure pore size, membrane diameter, and chemical compatibility match your fluid before ordering in the right-side checkout panel.

Related technical collections:
Lab Consumables |
Lab Glassware

Use Cases

Chemical Synthesis Filtration & Separation Pocket Size Portable Sample Preparation School Science Labs

FAQs

What is the difference between Slow, Medium, and Fast filtration speeds, and how do I choose the right one for my experiment?

The three speeds differ in pore size and filtration time. Slow speed (3–4 μm, 80–90 sec) is ideal for fine precipitates and samples requiring high clarity. Medium speed (7–8 μm, 50–60 sec) suits most routine laboratory filtrations. Fast speed (10–12 μm, 28–35 sec) works best for coarse particles or when rapid flow is needed. Choose based on your sample’s particle size and the desired filtrate clarity.

Which diameter of filter paper should I select for my funnel?

Match the filter paper diameter to your funnel’s top diameter. Recommended pairs: 7 cm paper fits 40–50 mm funnels, 9 cm fits 50 mm, 11 cm fits 60 mm, 12.5 cm fits 75 mm, and 18 cm fits 120 mm funnels. For 15 cm paper, use approximately 90–100 mm funnels. Ensure the paper sits comfortably inside the funnel with its edge below the rim after folding.

Can I use this qualitative filter paper for quantitative (gravimetric) analysis?

No. Xin Tester Qualitative Filter Paper is specifically designed for general qualitative analysis and removing suspended solids. It is not suitable for quantitative analysis because its ash content (<0.1%) is higher than that of quantitative grades and does not meet the strict weight‑consistency requirements for gravimetric work. For precise mass‑based analysis, please use dedicated quantitative filter paper.

What are the key usage tips, especially regarding temperature and reusability?

This filter paper can withstand temperatures up to 120°C, so it may be used for hot filtration within that limit – do not exceed it. The paper is intended for single use only; discard after each filtration to avoid cross‑contamination or clogging. Before use, always wet the paper with water to ensure it adheres firmly to the funnel wall, and keep the liquid level below the paper edge during filtration to prevent bypass and ensure proper separation.

Xin Tester Qualitative Filter Paper, 100% Cotton Cellulose Lab Solid-Liquid Separation Circles (100 Pcs)

Price range: $7.07 through $15.18

Extra 5% Off with code: welcome5

SIZE

Filtration Speed

Clear

6–12 Month Warranty

Repair & Refund support available for most products.

Free Worldwide Shipping

Ships within 3 business days.

Taxes & Duties

Buyer responsible for local import fees.

24/7 After-Sales Support

Technical assistance & video guidance within 24h.