A process for converting magnesium chloride into magnesium oxide having the steps of: subjecting a magnesium chloride solution to a spray drying step in a spray-drying apparatus at a temperature of 300-475° C., resulting in the formation of a spray-dried product having 10-80 wt. % magnesium oxide and 20-90 wt. % of the total of magnesium hydroxychloride and magnesium chloride, subjecting the product of the spray drying step to a roasting step in a roaster at a temperature of 600-900° C. in the presence of water, resulting in the formation of a product having at least 98 wt. % of MgO, and less than 2 wt. % of the total of magnesium hydroxychloride and magnesium chloride, wherein the percentages of MgO, magnesium hydroxychloride and magnesium chloride, are calculated on the total of MgO, magnesium hydroxychloride and magnesium chloride.

A process for converting magnesium chloride into magnesium oxide having the steps of: subjecting a magnesium chloride solution to a spray drying step in a spray-drying apparatus at a temperature of 300-475° C., resulting in the formation of a spray-dried product having 10-80 wt. % magnesium oxide and 20-90 wt. % of the total of magnesium hydroxychloride and magnesium chloride, subjecting the product of the spray drying step to a roasting step in a roaster at a temperature of 600-900° C. in the presence of water, resulting in the formation of a product having at least 98 wt. % of MgO, and less than 2 wt. % of the total of magnesium hydroxychloride and magnesium chloride, wherein the percentages of MgO, magnesium hydroxychloride and magnesium chloride, are calculated on the total of MgO, magnesium hydroxychloride and magnesium chloride.

A process is described for making acrylic acid from dextrose, which comprises fermenting dextrose; removing solids from the resulting fermentation broth; removing lactic acid from the clarified broth by extraction into an organic solvent; separating out the lactic acid-loaded organic solvent while recycling at least a portion of the remainder back to the fermentation step; reacting the lactic acid with ammonia to provide a dehydration feed comprising ammonium lactate while preferably recycling the organic solvent; carrying out a vapor phase dehydration of the ammonium lactate to produce a crude acrylic acid product; and purifying the crude acrylic acid by distillation followed by melt crystallization, chromatography or both melt crystallization and chromatography.

A process is described for making acrylic acid from dextrose, which comprises fermenting dextrose; removing solids from the resulting fermentation broth; removing lactic acid from the clarified broth by extraction into an organic solvent; separating out the lactic acid-loaded organic solvent while recycling at least a portion of the remainder back to the fermentation step; reacting the lactic acid with ammonia to provide a dehydration feed comprising ammonium lactate while preferably recycling the organic solvent; carrying out a vapor phase dehydration of the ammonium lactate to produce a crude acrylic acid product; and purifying the crude acrylic acid by distillation followed by melt crystallization, chromatography or both melt crystallization and chromatography.

Provided is a process for producing acrylic acid, the process comprising: (step 1) preparing a first aqueous lactic acid solution by diluting a lactic acid raw material with water; (step 2) heat exchanging the first aqueous lactic acid solution to form a vaporized second lactic acid vapor and an unvaporized third aqueous lactic acid solution; (step 3) including the unvaporized third aqueous lactic acid solution in the aqueous solution of the step 1; and (step 4) supplying and absorbing an absorption liquid to the vaporized second lactic acid vapor to form an absorbed fourth aqueous lactic acid solution and an unabsorbed fifth lactic acid vapor, wherein the absorption liquid is water or an aqueous lactic acid solution.

Provided is a process for producing acrylic acid, the process comprising: (step 1) preparing a first aqueous lactic acid solution by diluting a lactic acid raw material with water; (step 2) heat exchanging the first aqueous lactic acid solution to form a vaporized second lactic acid vapor and an unvaporized third aqueous lactic acid solution; (step 3) including the unvaporized third aqueous lactic acid solution in the aqueous solution of the step 1; and (step 4) supplying and absorbing an absorption liquid to the vaporized second lactic acid vapor to form an absorbed fourth aqueous lactic acid solution and an unabsorbed fifth lactic acid vapor, wherein the absorption liquid is water or an aqueous lactic acid solution.

The present invention relates to an improved process for producing polylactide where the goal is to recover a maximum of useful matters in order to recycle without loss and so significantly improving the global yield of the production process of polylactide when starting from lactic acid.

Liquid formulations of lactic acid addition salts of 1-[2-(2,4-dimethylphenylsulfanyl)-phenyl]piperazine are provided.

A catalyst system includes a complex having formula I which advantageously has a sterically protecting N-heterocyclic carbene (NHC) carbene-pyridine ligand to handle harsh reactions conditions than many prior art catalysts:

##STR00001##

wherein M is a transition metal; o is 0, 1, 2, 3, or 4; R.sub.1 is a C.sub.1-6 alkyl, a C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl. In a refinement, R.sub.1 is methyl, ethyl, butyl, n-propyl, isopropyl, n-butyl, sec-butyl, or t-butyl; R.sub.2, R.sub.3, R.sub.3′ are independently an optionally substituted C.sub.1-6 alkyl, halo (e.g., Cl, F, Br, etc), NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; R.sub.4, R.sub.4′ are independently an optionally substituted C.sub.1-6 alkyl, halo, NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; and X.sup.− is a negatively charge counter ion and L.sub.1, L.sub.2 are each independently a neutral ligand.

A catalyst system includes a complex having formula I which advantageously has a sterically protecting N-heterocyclic carbene (NHC) carbene-pyridine ligand to handle harsh reactions conditions than many prior art catalysts:

##STR00001##

wherein M is a transition metal; o is 0, 1, 2, 3, or 4; R.sub.1 is a C.sub.1-6 alkyl, a C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl. In a refinement, R.sub.1 is methyl, ethyl, butyl, n-propyl, isopropyl, n-butyl, sec-butyl, or t-butyl; R.sub.2, R.sub.3, R.sub.3′ are independently an optionally substituted C.sub.1-6 alkyl, halo (e.g., Cl, F, Br, etc), NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; R.sub.4, R.sub.4′ are independently an optionally substituted C.sub.1-6 alkyl, halo, NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; and X.sup.− is a negatively charge counter ion and L.sub.1, L.sub.2 are each independently a neutral ligand.