Thermolytic fragmentation of sugars

Abstract

A process for large scale and energy efficient production of oxygenates from sugar is disclosed in which a sugar feedstock is introduced into a thermolytic fragmentation reactor including a fluidized stream of heat carrying particles. The heat carrying particles may be separated from the fluidized stream prior to cooling the fragmentation product and may be directed to a reheater to reheat the particles and recirculate the heated particles to the fragmentation reactor.

1 . A process for thermolytic fragmentation of a sugar into C 1 -C 3  oxygenates, said process comprising the steps of:
 a. providing particles carrying heat and suitable for fluidization;   b. providing a fluidized bed fragmentation reactor comprising a riser and suitable for conducting thermolytic fragmentation and suitable for fluidizing a stream of particles;   c. providing a feedstock solution comprising a sugar;   d. introducing the particles into the reactor at a rate sufficient to maintain a temperature of at least 250° C., such as at least 300 350, 400 or 450° C., after the thermolytic fragmentation has taken place, and sufficient to obtain a fluidized stream of particles;   e. introducing the feedstock into the fluidized stream of particles to obtain thermolytic fragmentation of the sugar to produce a particle dense fragmentation product; then   f. separating a fraction of the particles from the particle dense fragmentation product to produce a particle lean fragmentation product;   g. quenching the particle lean fragmentation product at least 50° C. such that from introducing the feedstock into the particle containing fluidization stream to the quench is performed, the mean residence time of the gas is maximum 5, such as maximum 3 seconds, such as maximum 2, 1, 0.8 or 0.6 seconds;   h. recovering the crude fragmentation product,   i. transferring the particles separated in step f) to a reheater for heating; and   j. recirculating the heated particles to the fragmentation reactor.   
     
     
         2 . A system for fragmentation of a sugar composition into C 1 -C 3  oxygenates comprising a fragmentation reactor, said reactor comprising within the reactor,
 a riser   a first particle separator   a fluidization stream inlet   a particle inlet   a feedstock inlet   a particle outlet   a product outlet,   
       wherein the riser is arranged within and in the lower part of the fragmentation reactor; and the fluidization stream inlet and the particle inlet is arranged in the lower part of the riser; the feedstock inlet is arranged in the lower part of the riser above the particle inlet; the riser is adapted to fluidize particles in the riser; and the first particle separator is arranged in the upper part of the riser and is adapted to separate at least a part of the particles from a fluidization stream, and 
       wherein the fragmentation reactor further comprises a cooling section arranged downstream the first particle separator in relation to the gas stream, said cooling section being adapted to cool the fluidization stream exiting the first particle separator and the system further comprises a reheater for reheating particles exiting the fragmentation reactor, the reheater comprises a fuel and combustion air inlet, a burner, a reheater particle inlet, a reheater riser, a reheater particle separator, a reheater gas outlet and a reheater particle outlet.