Cream coloured molecular sieve pellets in a white dish

Representative photo. Your order is made to your specification by a verified seller. Photo: “Molecular sieve 4A crop” by Nao1958, CC0.

Molecular sieves 4A supplier in Bangladesh

Order through Roptan, your molecular sieves 4A supplier in Bangladesh. Tell us what you dry, the dew point you need, the bead size and the bed volume: we source desiccant-grade beads from a verified seller, check the lot and deliver sealed drums.

Verified sellers
Checked before it ships
Delivered by Roptan

Prefer to deal with suppliers yourself? Post it on the requirement board

Buying molecular sieves 4A in Bangladesh

Molecular sieve 4A is the sodium form of zeolite A, a synthetic aluminosilicate with pores of about 4 angstroms. Water and other small molecules enter the pores; larger ones stay out. It is the general drying grade of the zeolite family, used to dry gas streams, compressed air and laboratory solvents, and to keep sealed packs of drugs and electronic parts dry.

The name zeolite A also covers a detergent powder, usually the larger market by volume. As your molecular sieves 4A supplier in Bangladesh, Roptan states the form, bead size and duty in the order, compares verified sellers on that, checks the lot papers and delivers drums that stay sealed until you load them.

Kinds of molecular sieve, and where 4A fits

4A beads

Spherical beads, the usual choice for dryer vessels because they give a lower pressure drop and are mechanically robust. Choose 4A for general drying of gas, air and solvents.

4A pellets

The same zeolite in extruded form. Follow the dryer maker's specification for shape and size.

3A

The potassium form, with pores of about 3 angstroms. It takes up water but keeps ethanol out, so it is the grade for drying ethanol and petroleum cracking gas.

5A

The calcium form, used for air purification and pressure swing adsorption. Oxygen PSA units often use 5A or 13X types; nitrogen generators usually run on a carbon molecular sieve. Check the machine maker's specification.

13X

Larger pores, about 10 angstroms, used to dry and purify natural gas and in air separation. A 4A bed will not take up molecules that need the larger pore.

How to specify molecular sieve 4A

Duty: Name what is dried: natural gas, compressed air, a solvent or a sealed pack. State temperature, pressure, flow and cycle time.
Outlet dryness: Give the dew point or water content wanted at the outlet. Gas for LNG, for example, is usually dried to below 1 ppmv water to avoid blockages from ice or methane hydrate.
Form and size: Bead or pellet, with diameter in mm, and desiccant grade in writing, so the offer cannot be detergent powder.
Dryer type: For compressed air, say whether the sieve goes into a polishing dryer after a refrigerated one. Regenerative desiccant dryers typically reach dew points of minus 40 degrees Celsius or lower.
Regeneration: Sieves are regenerated by heating and purging, by vacuum or by pressure swing, at about 175 to 315 degrees Celsius depending on type. Ask for the grade's regeneration temperature and cycle life.
Bed quantity: Give the bed volume and ask for the bulk density of the grade. Listed values for 4A are about 0.60 to 0.65 g/mL; the lot's own figure sets the kilograms.

Papers to ask a molecular sieves 4A supplier in Bangladesh for

Certificate of analysis for the lot: Water adsorption, bulk density, crush strength and attrition, each with the seller's test method named. Sellers test to their own methods, so agree the method in the order.
21 CFR 182.2727 and E554: For food or drug contact only. Sodium aluminosilicate is listed by the US FDA under 21 CFR 182.2727 and carries the food additive number E554; ask for the matching declaration.
Safety data sheet to GHS: Required with every delivery. It covers handling and storage; keep sieves sealed and away from water, acids and alkalis.

What moves the price of molecular sieve 4A

Bead or pellet size, and how narrow a size range you ask for.
Strength and attrition limits stricter than a standard grade.
Exchanged grades: 3A and 5A are made from 4A by ion exchange, an extra step that usually shows in the price.
Packing: sealed drums or vacuum packs cost more than plain bags but protect the charge.
Quantity and freight: demand in Bangladesh is usually met by imports, so freight, clearance and the exchange rate count.

Lead times and delivery

Where a seller holds 4A beads in common sizes, delivery is usually quick. Other sizes, pellets and the 3A, 5A and 13X grades are usually brought in to order, which adds sea freight to Chattogram and customs clearance before delivery. Minimums depend on the seller and the packing. Roptan confirms the date and the minimum in the quote.

We deliver to your plant across Bangladesh in sealed drums or moisture-barrier packs, with the lot number matching the certificate of analysis, the safety data sheet to GHS and a VAT invoice (Mushak 6.3). Open each drum at the vessel and load it at once. If you want the dryer charged, we arrange it through the seller.

What we check for this order

Desiccant grade, not powderWe confirm the offer is for 4A beads or pellets of your size, not the detergent-grade zeolite powder sold under the same name.
Grade against dutyWe check the grade fits your duty: 3A for ethanol, and 5A or 13X where a PSA machine maker specifies them.
Lot certificateWe check the certificate of analysis for the lot against the values and test methods agreed in the order.
Seals intactWe check drums are sealed at dispatch and on arrival, because 4A takes up moisture from the air quickly.

Questions buyers ask

Should I use molecular sieve or silica gel in my dryer?

Silica gel suits general air and packaging duty and regenerates at about 120 degrees Celsius. Molecular sieve reaches much lower residual moisture, such as gas below 1 ppmv water, but needs about 175 to 315 degrees Celsius to regenerate. Choose sieves when the outlet must be very dry and the dryer is built for that heat.

Can I put 4A in our PSA oxygen or nitrogen generator?

Usually not. PSA units adsorb the target gas at high pressure and release it at low pressure, and each uses its own adsorbent: oxygen units often a 5A or 13X type, nitrogen generators usually a carbon molecular sieve. Send us the machine maker's specification, or the label from the old charge, and we source the grade it names.

Why does 4A have to stay sealed until loading?

It is strongly water-seeking. Daily humidity in Bangladesh reached 94 to 100 per cent in July in readings from 1986, so an open drum starts loading water before it reaches the vessel. Keep drums closed until loading and charge the dryer in one go.

Can spent 4A be regenerated on site?

Yes, that is how industrial desiccant dryers work, by heat and purge gas or by pressure swing. Ask the seller for the grade's regeneration temperature and cycle life, and plan the next charge around your dew point record.

How soon will I hear back about filter media?

Within 48 hours of a complete requirement, with a price and a delivery date. A requirement is complete when it has the quantity, where it is needed and by when.

Who do I deal with?

With Roptan, when Roptan manages the order: we buy from the verified seller and deliver to you. With the supplier directly, when you post on the requirement board and choose a quote yourself.