Thứ Sáu, 20 tháng 4, 2012

Sodium carbonate Na2CO3 China-technical-40kg Industry chemicals

Sodium carbonate
Na2CO3
China-technical-40kg
Industry chemicals
http://en.vietnamchemtech.com.vn/chitietSP.asp?id_pro=479

Product description :
Sodium carbonate (also known as washing soda or soda ash), Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as acrystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well known for its everyday use as a water softener. It can be extracted from the ashes of many plants. It is synthetically produced in large quantities from salt (sodium chloride) and limestone in a process known as the Solvay process.
Uses
The manufacture of glass is one of the most important uses of sodium carbonate. When combined with silica and calcium carbonate and heated to high temperatures, then cooled rapidly, glass is produced. This type of glass is known as soda lime glass.
Sodium carbonate is also used as a relatively strong base in various settings. For example, sodium carbonate is used as a pH regulator to maintain stable alkaline conditions necessary for the action of the majority of photographic developing agents.
It is a common additive in municipal pools used to neutralize the acidic effects of chlorine and raise pH.
In cooking, it is sometimes used in place of sodium hydroxide for lyeing, especially with German pretzels and lye rolls. These dishes are treated with a solution of an alkaline substance in order to change the pH of the surface of the food and thus improve browning.
In taxidermy, sodium carbonate added to boiling water will remove flesh from the skull or bones of trophies to create the "European skull mount" or for educational display in biological and historical studies.
In chemistry, it is often used as an electrolyte. This is because electrolytes are usually salt-based, and sodium carbonate acts as a very good conductor in the process of electrolysis. In addition, unlike chloride ions, which form chlorine gas, carbonate ions are not corrosive to the anodes. It is also used as a primary standard for acid-base titrations because it is solid and air-stable, making it easy to weigh accurately.
Domestic use
In domestic use, it is used as a water softener during laundry. It competes with the magnesium and calcium ions in hard water and prevents them from bonding with the detergent being used. Without using washing soda, additional detergent is needed to soak up the magnesium and calcium ions. Called washing sodasoda crystals, or sal soda in the detergent section of stores, it effectively removes oil, grease, and alcohol stains. Sodium carbonate is also used as a descaling agent in boilers such as those found in coffee pots, espresso machines, etc.
In dyeing with fiber-reactive dyes, sodium carbonate (often under a name such as soda ash fixative or soda ash activator) is used to ensure proper chemical bonding of the dye with cellulose (plant) fibers, typically before dyeing (for tie dyes), mixed with the dye (for dye painting), or after dyeing (for immersion dyeing).
Other applications
Sodium carbonate is a food additive (E500) used as an acidity regulator, anti-caking agent, raising agent, and stabilizer. It is one of the components of kansui, a solution of alkaline salts used to give ramen noodles their characteristic flavor and texture. It is also used in the production of snus (Swedish-style snuff) to stabilize the pH of the final product. In Sweden, snus is regulated as a food product because it is put into the mouth, requires pasteurization, and contains only ingredients that are approved as food additives.
Sodium carbonate is also used in the production of sherbet powder. The cooling and fizzing sensation results from the endothermic reaction between sodium carbonate and a weak acid, commonly citric acid, releasing carbon dioxide gas, which occurs when the sherbet is moistened by saliva.
In China, it is used to replace lye-water in the crust of traditional Cantonese moon cakes, and in many other Chinese steamed buns and noodles.
Sodium carbonate is used by the brick industry as a wetting agent to reduce the amount of water needed to extrude the clay.
In casting, it is referred to as "bonding agent" and is used to allow wet alginate to adhere to gelled alginate.
Sodium carbonate is used in toothpastes, where it acts as a foaming agent and an abrasive, and to temporarily increase mouth pH.
Sodium carbonate is used to create the photo process known as reticulation.
Sodium carbonate, in a solution with common salt, may be used for cleaning silver. In a non-reactive container (glass, plastic or ceramic) aluminium foil and the silver object are immersed in the hot salt solution. The elevated pH dissolves the aluminium oxide layer on the foil and enables an electrolytic cell to be established . Hydrogen ions produced by this reaction reduce the sulphide ions on the silver restoring silver metal. The sulphide can be released as small amounts of hydrogen sulphide. Rinsing and gently polishing the silver restores a highly polished condition. [4]
Identifiers
CAS number497-19-8 Yes
5968-11-6 (monohydrate)
6132-02-1 (decahydrate)
PubChem10340
ChemSpider9916 Yes
UNII45P3261C7T Yes
EC number207-838-8
ChEBICHEBI:29377 Yes
ChEMBLCHEMBL186314 Yes
RTECS numberVZ4050000
Jmol-3D imagesImage 1
Properties
Molecular formulaNa2CO3
Molar mass105.9784 g/mol (anhydrous)
124.00 g/mol (monohydrate)
286.14 g/mol (decahydrate)
AppearanceWhite solid, hygroscopic
OdorOdorless
Density2.54 g/cm3 (anhydrous)
2.25 g/cm3 (monohydrate)
1.51 g/cm3 (heptahydrate)
1.46 g/cm3 (decahydrate)
Melting point
851 °C (anhydrous)[1]
100 °C (decomp, monohydrate)
33.5 °C (decomp, decahydrate)
32 °C (heptahydrate)
Boiling point
1633 °C (anhydrous)
Solubility in water7 g/100 mL (0 °C)
21.6 g/100 mL (20 °C)[1]
450 g/L (100 °C)[2]
Solubilityinsoluble in ethanolacetone
Basicity (pKb)4.67
Refractive index(nD)1.485 (anhydrous)
1.420 (monohydrate)
1.405 (decahydrate)
Structure
Coordination
geometry
trigonal planar
Thermochemistry
Std enthalpy of
formation
 ΔfHo298
−1131 kJ·mol−1[3]
Standard molar
entropy
 So298
136 J·mol−1·K−1[3]
Hazards
MSDSMSDS
EU Index011-005-00-2
EU classificationIrritant (Xi)
R-phrasesR36
S-phrases(S2)S22S26
NFPA 704
NFPA 704.svg
0
1
1
Flash pointNon-flammable
LD504090 mg/kg (rat, oral)
Related compounds
Other anionsSodium bicarbonate
Other cationsLithium carbonate
Potassium carbonate
Rubidium carbonate
Caesium carbonate
Related compoundsAmmonium carbonate
Natron
Sodium percarbonate

Thứ Tư, 18 tháng 4, 2012

Sodium metabisulfite Na2S2O5 Italia-Foog grade-25kg Pharmaceuticals & fine Chemical

Sodium metabisulfite
Na2S2O5
Italia-Foog grade-25kg
Pharmaceuticals & fine Chemical
http://en.vietnamchemtech.com.vn/chitietSP.asp?id_pro=478

Product description :
Sodium metabisulfite or sodium pyrosulfite (IUPAC spelling Br. E. sodium metabisulphite or sodium pyrosulphite) is an inorganic compound of chemical formula Na2S2O5. The substance is sometimes referred to asdisodium (metabisulfite). It is used as a disinfectantantioxidant and preservative agent.
Uses
Food additive
It is used as a preservative and antioxidant in food and is also known as E223.[3]
It may cause allergic reactions in those who are sensitive to sulfites, including respiratory reactions in asthmatics,anaphylaxis and other allergic reactions in sensitive individuals.[4][5]
Sodium metabisulfite and potassium metabisulfite are the primary ingredients in Campden tablets, used for wine andbeer making.[6]
The acceptable daily intake is up to 0.7 mg per kg of body weight.[7] Sodium metabisulfite has no side effects it is oxidised in the liver to harmless sulfate and excreted in urine.[8][clarification needed]
Sanitization and cleaning agent
It is commonly used in homebrewing and winemaking to sanitize equipment. It is used as a cleaning agent for potable water reverse osmosis membranes in desalination systems. It is also used to remove chloramine from drinking water after treatment.
Other uses

Natri metabisunfit Na2S2O5 Ý-TP-25kg Phụ gia thực phẩm http:

Natri metabisunfit
Na2S2O5
Ý-TP-25kg
Phụ gia thực phẩm
http://vietnamchemtech.com.vn/chitietSP.asp?id_pro=73
Mô tả sản phẩm:

Natri metabisunfit hay natri pyrosunfit là hợp chất vô cơ có công thức Na2S2O5. Nó được dùng làm chất tẩy uế, chất chống ôxy hóachất bảo quản.

Sử dụng

Phụ gia thực phẩm

Nó được dùng làm chất chống oxi hóa và chất bảo quản trong thực phẩm và còn được biết dưới tên E223.[2]
Nó có thể gây tác dụng dị ứng đối với những thứ nhạy cảm với sunfit, bao gồm các ảnh hưởng đến hệ hô hấp như hen phế quản, tính quá mẫn cảm và các ảnh hưởng riêng biệt khác.[3][4]
Natri metabisunfit và kali metabisunfit là thành phầm cơ bản trong viên Campden, dùng trong sản xuất biarượu. [5]
Liều dùng cho phép mỗi ngày là đến 0.7 mg trên mỗi kg khối lượng cơ thể.[6] Natri metabisunfit không có tác dụng phụ; nó bị oxi hóa trong gan chuyển thành sunfat vô hại và thải ra theo đường tiết niệu.[7]

Chất chùi rửa và sát trùng

Nó thường dùng trong việc ủ bia tại gia và nấu rượu để sát trùng các thiết bị và dụng cụ. Nó còn làm chất chùi rửa cho màng thẩm thấu ngược (RO) trong sản xuất nước sạch trong hệ thống tách muối khỏi nước biển. Nó còn dùng để loại bỏ cloramin ra khỏi nước uống sau khi xử lý.

 Các ứng dụng khác

  • Trong ngành nhiếp ảnh.[8]
  • Dung dịch đậm đặc để loại bỏ các gốc cây. Một vài loại chứa dung dịch nồng độ 98%, và làm biến chất lignin trong gốc cây, tạo thuận lợi cho việc loại bỏ nó.[9]
  • Làm tá dược trong một số thuốc, như paracetamol. Xấp xỉ 0.5 mg trong máy phun adrenalin như EpiPen.
  • Một khía cạnh liên quan đến sức khỏe rất quan trọng của chất này là nó có thể được cho vào một mẫu máu trong một phép thử cho hội chứng tế bào hình liềm ( một hình thứ tương tự khác của sự đột biến hemoglobin). Chất này gây cho tế bào bị chết đến hình liềm (thông qua các phản ứng polyme hóa phức tạp) do đó chứng thực đã nhiễm bệnh.
Tên khác Natri pyrosunfit
Natri đisunfit
Nhận dạng
Số CAS [7681-57-4]
PubChem 24346
Số EINECS 231-673-0
Số RTECS UX8225000
Thuộc tính
Công thức phân tử Na2S2O5, Na-O-(S=O)-O-(S=O)-O-Na
Phân tử gam 190.107 g/mol
Bề ngoài dạng bột trắng
Tỷ trọng 1.48 g/cm3
Điểm nóng chảy >170 °C (bắt đầu ở 150 °C)
Độ hòa tan trong nước 54 g/100 ml
Các nguy hiểm
MSDS Mallinckrodt MSDS
Phân loại của EU Có hại (Xn)
Chất gây kích thích (Xi)
Chỉ mục EU 016-063-00-2
NFPA 704
NFPA 704.svg
0
2
0
 
Chỉ dẫn R R22, R31, R41 (xem Danh sách nhóm từ R)
Chỉ dẫn S S2, S26, S39, S46 (xem Danh sách nhóm từ S)
Các hợp chất liên quan
Anion khác Natri sunfit
Natri bisunfit
Cation khác Kali metabisunfit
Hợp chất liên quan Natri đithionit
Natri thiosunfat
Natri sunfat

Thứ Ba, 17 tháng 4, 2012

Trichloroisocyanuric acid 200g tablet C3Cl3N3O3 Japan-90%-50kg Chemicals for pool

Trichloroisocyanuric acid 200g tablet
C3Cl3N3O3
Japan-90%-50kg
Chemicals for pool
http://en.vietnamchemtech.com.vn/chitietSP.asp?id_pro=466

Product description :
Trichloroisocyanuric acid is the organic compound with the formula (C3Cl3N3O3). It is used as an industrial disinfectant, bleaching agent and a reagent in organic synthesis.[1][2] This white crystalline powder, which has a strong "chlorine odour," is sometimes sold in tablet or granule form for domestic and industrial use.
Use in water treatment
The compound is a disinfectant, algicide and bactericide mainly for swimming pools and dyestuffs, and is also used as a bleaching agent in the textile industries.
Applications: It is widely used in civil sanitation, pools and spas, preventing and curing diseases in husbandry and fisheries, fruits and vegetables preservation, wastewater treatment, algaecide for recycling water of industry and air conditioning, anti shrink treatment for woolen, treating seeds, bleaching fabrics, and organic synthesis industry
Benefits of TCCA in Swimming Pool-
  • Available with 90% chlorine concentration
  • Due to high chlorine content, handling is easy for large pools.
  • Reduces chlorine loss during day time. TCCA is stable it does not strip like any other halogen compounds.
  • Reduces algae growth.
  • Dissolves slowly in water, allowing for continuously metered dosing of available chlorine, especially when in tablet form.
Drawbacks of TCCA in Swimming Pool-
  • Cyanuric Acid (CYA) build-up from TCCA use can decrease the effectiveness of Free Active Chlorine (FAC) over time.
  • Such build up can only be reduced by dilution with water that does not contain CYA.
  • The economics of this effect can greatly reduce the cost-effectiveness of high chlorine availability in TCCA.
  • At high CYA concentrations, normal chlorine levels can be rendered ineffective, requiring either dilution by draining and refilling the pool or by adding abnormally high doses of chlorine to overcome this effect.

Thứ Hai, 16 tháng 4, 2012

Sodium peroxide Na2O2 China-AR-0,5kg China chemical reagent

Sodium peroxide
Na2O2
China-AR-0,5kg
China chemical reagent
http://en.vietnamchemtech.com.vn/chitietSP.asp?id_pro=451

Natri peroxit Na2O2 AR 500g Hóa chất tinh khiết TQ

Natri peroxit
Na2O2
AR 500g
Hóa chất tinh khiết TQ

http://vietnamchemtech.com.vn/chitietSP.asp?id_pro=62