Facile method to manipulate the molecular weight and practical mass production of chitosan by mechanical shearing and concurrent ultrafiltration treatment

Abstract

The objective of this study was to propose a facile method to manipulate the molecular weight and practical mass production of chitosan by mechanical shearing and concurrent ultrafiltration (UF) treatment. The proposed method was based on the degradation rate and rate constant of various process variables, such as: solution temperature, reaction time, concentration of chitosan solution, with or without concurrent removal of degraded fragments during mechanical shearing. The result obtained was that the degradation rate constant was 1.8-6.0 times higher for those using UF to remove smaller degraded molecules concurrently during treatment, than that without UF treatment. The degradation rate constant increased with increasing solution temperature; however, the solution temperature should not exceed than 50 C to prevent the undesired color changes of the resulting product. A method combining mechanical shearing/UF treatment at 50 C and ultrasonic radiation or microfluidization/UF treatment at 30 C is proposed here for a facile method to manipulate the molecular weight of the resultant chitosan with an energy saving, efficient and practical mass production.

Application of Polysaccharide Biopolymer in Petroleum Recovery

“…However, the enzymatic treatment is only feasible for the production in lab-scale due to its high cost [ 53 ]. The principle of mechanical methods lies in the physical force to break the chemical bonds between units of Chitin or Chitosan and the physical force can be generated from shearing, ultrasonication, and micro fluidization flow [ 54 , 55 , 56 ]. The mechanical method is environmentally friendly, energy effective, and effects are focused on increasing its process rate.…”

“…Amphoteric cellulose can be synthesized by The commercial cellulose in the microcrystalline structure and the manufacturing process was shown in Figure 7. First, pure cellulose is separated from plants with physical or chemical processes [56]. Then, acid hydrolysis of cellulose is conducted with 1-2.5 M HCl or H 2 SO 4 solution at 80-105 • C aiming to selectively remove the amorphous region of cellulose fiber, but retain the microcrystalline region [75].…”