Cofco (Jilin) Bio-Chemical Technology Co., Ltd

Nutrition & Health Research Institute, Cofco Corporation

Cofco Biotechnology Co., Ltd.

Jilin Cofco Biomaterial Co., Ltd

Tsinghua University

Tai An

Bo Chen

Wei Lin

Yi Tong

Lida Wu

Fang Tian

Kai Yang

Xiaoyan Wang

Kejia Xu

Chao Peng

Yuanheng Guo

Dayong Li

Haijun Liu

Weiqiang Zhou

Yuan Zhang

Qiong Wu

Peng Chen

Jin Tao

Zhaoning Cui

Zhigang Liu

Guoqiang Chen

Anni Liu

Xuemei Shen

Provided a method for separating PHA and PHA prepared therefrom. The method comprises the following steps: subjecting a PHA fermentation broth to solid-liquid separation to obtain a thallus precipitate; breaking cell walls of the thallus precipitate, and subjecting obtained wall-broken products to a plate and frame filtration to obtain PHA; a filter cloth for the plate and frame filtration is pre-coated with a PHA layer. The method adopts a plate and frame separation to replace the traditional centrifugal separation to prepare PHA, and the PHA layer is pre-coated on the filter cloth for the plate and frame filtration, thereby overcome the defects in the prior art such as high cost and operational difficulty caused by adopting multiple centrifugal separations; in addition, the method of the present disclosure also exhibits the advantages of high recovery rate of PHA and high purity of the prepared PHA product.

Method for separating PHA and PHA prepared therefrom

The present invention relates to the field of high polymer material manufacturing, and discloses an air-isolated continuous feeding system for synthesizing polylactic acid from lactide and a feeding method thereof. The continuous feeding system comprises a raw material bag/box and a raw material collector for collecting and outputting lactide, the raw material bag/box is connected with a shielding gas input pipeline, a discharge pipe is movably inserted into the raw material bag/box, a cyclone separator is connected downstream of the discharge pipe, and a solid substance outlet of the cyclone separator is connected with the raw material collector. According to the invention, deterioration of the lactide raw material incurred by moisture absorption and oxidation is avoided, and the reaction conversion ratio and final product purity are improved. The continuous feeding system is easy to operate, can save manpower and material resources, and is applicable to industrial application.

Air-isolated continuous feeding system for synthesizing polylactic acid from lactide and feeding method thereof

A method for efficiently producing PHA comprising: inoculating PHA fermentation strains into a fermentation medium for fermentation under the condition of being capable of producing PHA through fermentation; subjecting the fermentation broth to a solid-liquid separation to obtain fermentation supernatant and thallus precipitate; breaking the cell walls of the thallus precipitate, and subjecting the wall-broken products to a plate and frame filtration to prepare PHA; pre-coating a filter cloth for the plate and frame filtration with a PHA layer; at least part of the water of the fermentation medium is PHA process wastewater. The method utilizes the PHA process wastewater as at least part of the water of the fermentation medium, and filters and separates the broken thallus with the plate and frame filtration equipment pre-coated with PHA layer to prepare PHA, thereby recycling the high-salt wastewater, reducing costs, and potentially separating PHA on a large scale for industrial production.

Method for efficiently producing PHA

The present disclosure relates to the technical fields of genetic engineering and microbial fermentation, and discloses a recombinant strain for producing L-lactic acid, wherein the recombinant strain is obtained by genetically modifying a starting strain, the activity of D-lactate dehydrogenase of the recombinant strain is weakened or inactivated, and the activity of L-lactate dehydrogenase is enhanced, as compared with the starting strain. The present invention can significantly improve the fermentation effect, the yield of the L-lactic acid and the optical purity of the product L-lactic acid.

Recombinant strain for producing L-lactic acid

The present disclosure relates to the technical field of biotechnology and polymer synthesis, and discloses a method for producing polylactic acid, the method comprises the following steps: (i) inoculating a lactic acid fermentation strain into a lactic acid fermentation culture medium to perform a fermentation, so as to obtain a fermentation broth containing lactate; (ii) separating the fermentation broth to obtain a lactic acid; (iii) synthesizing a polymer-grade lactide by using the lactic acid as a raw material; (iv) subjecting the polymer-grade lactide to a polymerization reaction in a polymerization reaction device to obtain a polylactic acid. Through the above technical solution, the polylactic acid can be efficiently produced in the present disclosure.

Method for producing polylactic acid

The present invention relates to the field of devolatilization, and discloses a polylactic acid devolatilization evaporator, which comprises: a container comprising a cylinder; an agitating shaft coaxial with the cylinder; an agitating belt connected to the agitating shaft and arranged in a spiral shape around the central axis of the cylinder, comprising an outer belt surface facing the inner circumferential surface of the cylinder and spaced apart from the inner circumferential surface of the cylinder. With the above technical scheme, the agitating belt makes the materials distributed more uniformly on the inner circumferential surface of the cylinder and form a thin layer in uniform thickness, thereby avoids agglomeration of the materials, facilitates uniform heating of the materials, avoids deterioration (e.g., darkened color) of the materials owing to non-uniform heating of the materials and excessive retention time in a high-temperature environment, and improves product quality.

Polylactic acid devolatilization evaporator

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Beijing, China

Tai An