Maleic anhydride   is an   organic compound   with the formula C ₂ H ₂ (CO) ₂ O. It is the   acid anhydride   of   maleic acid . It is a colorless or white solid with an acrid odor. It is produced industrially on a large scale for applications in   coatings   and   polymers .

 

Maleic anhydride   is produced by vapor-phase oxidation of   n -butane . The overall process converts the methyl groups to carboxylate and   dehydrogenates   the backbone. The selectivity of the process reflects the robustness of maleic anhydride, with its conjugated double-bond system. Traditionally maleic anhydride was produced by the   oxidation   of   benzene   or other   aromatic compounds . As of 2006, only a few smaller plants continue to use benzene.

In both cases, benzene and butane are fed into a stream of hot air, and the mixture is passed through a catalyst bed at high temperature. The ratio of air to hydrocarbon is controlled to prevent the mixture from igniting.   Vanadium pentoxide   and   molybdenum trioxide   are the catalysts used for the benzene route, whereas   vanadium phosphate   is used for the butane route:

C ₄ H ₁₀   + 3.5 O ₂   → C ₄ H ₂ O ₃   + 4 H ₂ O H = −1236 kJ/mol

The main competing process entails full combustion of the butane, a conversion that is twice as exothermic as the partial oxidation.

The traditional method using benzene became uneconomical due to the high and still rising benzene prices and by complying with the   regulations   of benzene   emissions . In addition, in the production of maleic anhydride (4 C-atoms) a third of the original carbon atoms is lost as carbon dioxide when using benzene (6 carbon atoms). The modern catalytic processes start from a 4-carbon molecule and only attaches   oxygen   and removes water; the 4-C-base body of the molecule remains intact. Overall, the newer method is therefore more   material efficient .

Maleic anhydride is used in many applications.

Around 50% of world maleic anhydride output is used in the manufacture of unsaturated polyester resins (UPR). Chopped glass fibers are added to UPR to produce fiberglass reinforced plastics that are used in a wide range of applications such as pleasure boats, bathroom fixtures, automobiles, tanks and pipes.

Maleic anhydride is hydrogenated  used in the production of thermoplastic polyurethanes, elastane/Spandex fibers, polybutylene terephthalate (PBT) resins and many other products.

Diels-Alder reaction of maleic anhydride and butadiene and isoprene gives the respective tetrahydrophthalic anhydrides which can be hydrogenated to the corresponding hexahydrophthalic anhydrides. These species are used as curing agents in epoxy resins. Another market for maleic anhydride is lubricating oil additives, which are used in gasoline and diesel engine crankcase oils as dispersants and corrosion inhibitors. Changes in lubricant specifications and more efficient engines have had a negative effect on the demand for lubricating oil additives, giving flat growth prospects for maleic anhydride in this application.

A number of smaller applications for maleic anhydride. The food industry uses malic acid which is derivative of maleic anhydride in artificial sweeteners and flavour enhancements. Personal care products consuming maleic anhydride include hair sprays, adhesives and floor polishes. Maleic anhydride is also a precursor to compounds used for water treatment detergents, insecticides and fungicides, pharmaceuticals, and other copolymers.

Shandong Near Chemical Co.,Ltd is located in the beautiful Yellow River Delta , the mouth of the Yellow River into the sea - Dongying City . W ith a registered capital of 30 million yuan , it  was founded in 2011  and has grown rapidly with total assets   180   million   yuan and 100 employees. Near Chemical is a comprehensive service company focusing on import & export of chemicals and domestic trade. We are integrating rich chemical resources along with  individual customized services for all global clients.
Our company adheres to the market-oriented, committing to exploring the diversified international market, as well as the principle of honesty and trustworthiness. The clients of Near Chemical always come first.
In the past decade , Near Chemical has established a stable and friendly partnership with thousands of customers over 60 countries and regions. We have spread wide range of chemicals in  various  fields such   as pharmac y ,   petroleum, animal husbandry, food   processing, printing&dyeing, manufacturing industr ies etc. Near Chemical now has warehousing, trading, public utilities ,property management and other comprehensive entities, and gradually develop to collectivization, internationalization and Industrialization. Our company has a good development prospect and unlimited potential future.
Our main production lines are including Methylene Chloride 30,000 tons/year, Maleic Anhydride 30,000 tons/year, Propylene Glycol 20,000 tons/year.   
Meanwhile, we specialized in offering the following chemicals: Aniline,Dimethyl  F ormamide,Isopropanol ,Toluene diisocyanate,Polyether P olyol ,Polymer Polyol,  Methyl Acetate, Ethyl Acetate, Butyl Acetate, Glacial Acetic Acid, Potassium Hydroxide, Nitrile Butadiene Rubber Latex, Caustic Soda, Dipropylene Glycol, Ethylene Glycol, Phenol, Phthalic Anhydride, C yclohexanone, Thiourea, Barium Carbonate, Aluminum Chloride, Calcium Nitrate, N-propanol, Methyl Ethyl Ketone, Methanol, Ethanol, C yclohexane, Dimethyl Carbonate,  Dichlorodifluoromethane, Dichlorofluoromethane, Trichloroethylene, Tetrachloroethylene, Epichlorohydrin, Sodium Hydroxide Liquid, etc.
We always carry out   "quality first and service the best" .  

Near Chemical, Near U, W arm the world.

 

1 Q:Are you manufacture r ?
A: Yes, We are the largest manufacture on Methylene Chloride, Chloroform and Aniline oil. And ready stock on cyclohexanone, Dimethyl Formamide, Propylene Glycol, Ethylene Glycol, Dimethyl Carbonate, Thiourea, Polyol, TDI, IPA, Ethanol etc.

2 Q: How can you guarantee your quality?
A: Our factory owns mature production line under EPR quality system. We can guarantee the stab ility  and qualifi cation of the raw  material s . And we also have SOP loading system to ensure the safety and timely transportation.

3 Q: Can I get some samples?
  A:  Yes, we can supply sample s free of charge ,  the courier shipping cost will b e pre paid by customers.

4 Q: How to confirm the Product Quality before placing orders?
  A :  You can get free samples from us or taking our previous SGS Report s  as reference or arrange SGS before loading.

5 Q: What is your MOQ ?
A: Our MOQ is 20'FCL for each product.

6 Q: What  kind of package do you have?
A: We have many different packages to meet needs of our customers,like Iron drums, plastic drums,  IBC d rums, Flexitank, ISO TANK and bags etc.


7  Q :Which kind of payment terms do you accept?
A: TT, LC at sight/ LC 90/120days payment terms are acceptable.  

8  Q:Can you give me a discount price?
A: Yes. It depends on your order qty.

9  Q: How about your delivery? How long is your delivery time?
A: Prompt and reliable delivery by professional shipping line s .
Generally it takes 14  days after deposit or original LC.