31 results about "SALT RETENTION" patented technology

The invention belongs to the technical field of filtering materials, and discloses a non-woven cloth based forward osmosis membrane as well as a preparation method and application thereof. The non-woven cloth based forward osmosis membrane comprises a non-woven cloth support layer and a polyamide active layer, wherein the polyamide active layer is compounded on the non-woven cloth support layer; the quantity of the non-woven cloth support layer is 5-40 g / m<2>; the thickness of the non-woven cloth support layer is 10-55 [mu]m; the average aperture of the non-woven cloth support layer is 5-35 [mu]m; the porosity of the non-woven cloth support layer is greater than or equal to 80%. Wet-method non-woven cloth is used as a support layer material, and the polyamide active layer is prepared from a water-phase solution with alkylated fatty amine or a multi-functional amino compound and an oil-phase solution with an acid chloride compound on the wet-method non-woven cloth via upper-interface polymerization. The water flux of the forward osmosis membrane disclosed by the invention is as high as 80.9 L / (m<2>*h), and the salt retention rate of the forward osmosis membrane is greater than or equal to 97%. The water flux of the forward osmosis membrane is far higher than that of a conventional commercial forward osmosis membrane, and meanwhile a high salt retention rate is maintained. The forward osmosis membrane can be applied to fields such as sweater treatment and wastewater recycling.

Disclosed are methods of preparing antifouling coatings on reverse osmosis membranes with initiated chemical vapor deposition. The coatings enhance the stability and lifetime of membranes without sacrificing performance characteristics, such as permeability or salt retention.

A calcium lactate crystal inhibitor is added to the typical cheese-making recipe to inhibit the growth of calcium lactate crystals as the cheese ages. The calcium lactate crystal inhibitor is preferably a sodium salt of an organic acid, and is preferably added with sodium chloride or shortly after sodium chloride as part of the salting step. The calcium lactate crystal inhibitor can be identified in a solubility model as being effective in preventing calcium lactate crystal formation by having no or essentially no visually observable crystals and a minimal reduction (less than 5.0%, and more preferably less than 1.0%) in the calcium and lactate content of a calcium L-lactate pentahydrate solubility solution after 14 days of storage at 7° C. The amount of calcium lactate crystal inhibitor salt is within the range of greater than zero to 10% of the weight of the curd, to result in a cheese having 0.26 to 2.8% calcium lactate crystal inhibitor in a cheddar cheese. The amount of calcium lactate crystal inhibitor salt added for other cheeses can be based upon the lactate content and salt retention of the cheese.

Sodium gluconate is added to the typical cheese-making recipe to inhibit the growth of calcium lactate crystals as the cheese ages. The sodium gluconate is preferably added with sodium chloride or shortly after sodium chloride as part of the salting step. The amount of sodium gluconate is within the range of greater than zero to 10% of the weight of the curd, to result in a cheese having 0.26 to 2.8% gluconate in the cheese. The amount of sodium gluconate added for other cheeses can be based upon the lactate content and salt retention of the cheese.

The invention relates to a sulfonated polyphenol nanofiltration membrane and a preparation method thereof, comprising a supporting bottom membrane and a separation surface layer, wherein the separation surface layer is formed by a cross-linked reaction product of sulfonated polyphenols and aromatic acid chlorides. Due to the introduction of sulfonic acid groups in the present invention, on the one hand, it can regulate the interfacial polymerization process to obtain a smooth and loose interfacial polymerization layer; on the other hand, it can endow the nanofiltration membrane with higher hydrophilicity and negative charge, ensuring high At the same time of salt interception, the water flux of the membrane is greatly improved, and it also has good anti-pollution ability, and has great industrialization potential.

Disclosed is a semipermeable membrane and its preparation method. The semipermeable membrane obtained has a Turing structure. The Turing structure is an ordered pattern composed of microstructures. The existence of the structure enables the semipermeable membrane of this invention to have both high water permeation flux and excellent salt retention performance, which breaks the flux limit value of the semipermeable membrane while ensuring high selective permeability of the membrane. It also has good anti-pollution properties. The preparation method of the invention can be easily integrated into the existing semipermeable membrane production line without further cost input which has far-reaching practical significance and commercial value.

Disclosed are methods of preparing antifouling coatings on reverse osmosis membranes with initiated vapor deposition or oxidative vapor deposition. The coatings enhance the stability and lifetime of membranes without sacrificing performance characteristics, such as permeability or salt retention.

The present invention provides a polyamide reverse osmosis composite membrane and a preparation method thereof. According to the present invention, polyarylene ether sulfone with side carboxyl is added to a membrane casting liquid of a support layer to prepare a porous support layer of a reverse osmosis composite membrane, and a reverse osmosis function layer is compounded on the porous support membrane, wherein the hydrophilicity of the support layer and the binding performance between the polyamide function layer and the support layer are increased through the polyarylene ether sulfone with side carboxyl so as to increase the chemical resistance stability of the composite membrane interface, and the flux and the salt retention rate of the reverse osmosis composite membrane are improved. The method of the present invention has the simple process and is suitable for industrial production.

Disclosed are methods of preparing antifouling and chlorine-resistant coatings on reverse osmosis membranes with initiated chemical vapor deposition. The coatings enhance the stability and lifetime of membranes without sacrificing performance characteristics, such as permeability or salt retention.