Method 1: a method for producing L-cysteine hydrochloride monohydrate, the device is equipped with a ceramic reactor, a filter, an electrolytic cell, a concentration kettle, a vacuum dryer, a pulverizer, and a packing machine, and the L- Cystine, hydrochloric acid, activated carbon, and water are used as raw materials, and L-cysteine hydrochloride monohydrate is prepared through processes such as decolorization after acid addition, filtration, electrolysis, concentration, filtration, drying, crushing, and packaging. The technical solution is:
(1) Put L-cystine into the ceramic reaction kettle, add water five times the weight of L-cystine, start the agitator at a speed of 20 rpm, and dilute the L-cystine and water into a viscous Liquid, slowly add hydrochloric acid to the ceramic reactor, stop adding hydrochloric acid when the pH value in the ceramic reactor is adjusted to 1-1.2, stir and react for 2-2.2 hours, at this time, add catalyst activated carbon to the ceramic reactor, the quantity is L – 2-2.2% of the weight of cystine, while raising the temperature to 60° C. and stirring for 0.5-0.6 hours to carry out the decolorization reaction.
(2) Cool down to normal temperature, send the material in the ceramic reactor to the filter for filtration, and discharge and recover the solid impurities obtained after filtration, and send the liquid part to the electrolytic cell for electrolysis for 10-10.5 hours. After the electrolysis, the material is sent to the concentrated The kettle is concentrated to one-half of the original liquid volume, and the concentrated material is sent to a filter to filter out the liquid and discharged for recovery. The solid part is sent to a vacuum dryer for drying at a drying temperature of 70-75°C. The time is 3-3.5 hours, and the L-cysteine hydrochloride monohydrate solid is obtained after drying.
(3) Send the obtained L-cysteine hydrochloride monohydrate solid into a pulverizer to be pulverized into a uniform powder, and then send it into a packaging machine, and after the product powder is packaged, a finished product is obtained.
Method 2: a production method of L-cysteine hydrochloride monohydrate, which is characterized in that it consists of the following steps:
(1) Put the L-cystine into the ceramic reaction kettle, add an appropriate amount of water, start the agitator at a speed of 25 rpm, and dilute the L-cystine and water into a viscous liquid. At this time, add 9‑11 equivalent hydrochloric acid After being filtered through a precision filter, slowly add to the ceramic reactor, measure the pH value between 0.8-1.2, add catalyst activated carbon, the amount is 2% of the weight of L-cystine, and then send steam to start heating, when the temperature rises to Insulate and stir for 0.5 hours at 58°C-62°C.
(2) After the reaction, the materials in the ceramic reaction kettle are sent to the decolorization reaction kettle for decolorization. After decolorization, they are sent to the filter for filtration. The filtered filtrate is sent to the electrolytic cell for electrolysis for 9-11 hours. After the electrolysis, the materials are filtered with After filtering by machine, L-cysteine hydrochloride solution was obtained.
(3) Send the L-cysteine hydrochloride solution into a ceramic reactor for heating and concentration under reduced pressure, and send the concentrated and crystallized material into a centrifuge for solid-liquid separation to obtain a solid L-cysteine hydrochloride monohydrate.
(4) Send the obtained L-cysteine hydrochloride monohydrate solid into a vacuum dryer for drying at a drying temperature of 75°C-85°C and a drying time of 4-6 hours to obtain L-cysteine hydrochloride monohydrate The obtained L-cysteine hydrochloride monohydrate crystals are sieved, and then packaged to obtain the L-cysteine hydrochloride monohydrate finished product.