Marijuana Microwave Irradiation Degumming Process And Mechanism Studies

Hemp fiber is one kind of the bast fibers, its single fiber is relatively soft, textiles could avoid the hard feeling and the prickle, relatively soft and fitting. Hemp fiber has the advantages of fineness, good absorption, air permeability, shielding radiation and bacterial inhibition. Along with the improvement of the standard of living, people's dresses of their own require to be increased also. People enjoy clothing made by natural fibers more and more at the same time. So the fiber and the fabric are appreciated by consumers. Hemp fiber is the most prospective cellulosic fiber in the future.However, degumming of hemp fiber for textiles processing and applications is a very complicated process, it is closely related to the environment issues, ecological concerns, production costs, resource balance, and future demand for clothing. Compared with flax and ramie, the content of non-cellulose in hemp is as high as 40%. It makes the hemp degumming more difficult than flax and ramie. There are several methods for the hemp dugumming:natural fermentation, mechanical degumming, chemical dugumming, biological degumming, explosion degumming and ultrasonic degumming. However, it still exists various kind of problems and must be resolved,To resolve the problems of the degumming, Microwave-assisted extraction (MAE) combined with alkali-H2O2 one bath chemical process was used to obtain hemp fiber. The MAE used in alkali-H2O2 one-bath degumming which can be employed to the hemp fibers to remove non-cellulosic compounds, separate hemp fibres from their bundles, and modify the hemp fiber surface. Barium peroxide (BaO2) as a photoinitiator, an oxidant, bleaching agent and catalyst is introduced. The MAE degumming can remove the gum more effectively with shorter time, lower cost and consumption.In the MAE pretreatment, the quadratic regressive orthogonal design is employed to get the highly precise equation, in which the variables of MAE sulfuric acid pretreatment time and temperature, concentration and the ratio are considered to be the main technological parameters of MAE sulfuric acid pretreatment and alkali-H2O2 one bath degumming and bleaching of raw hemp. And the key technological parameters are also obtained by the quadratic regressive orthogonal design. In the MAE and alkali-H2O2 one bath degumming, the best range of the parameters are carried out by a series of tentative experiments, obtained the regression equation with high precision and the relations between the main parameters (MAE time, MAE temperature and BaO2 concentration) and the efficiency of wiping off gum and lignin, finding the best degumming parameters. The results show that MAE pretreatment time 18 min, MAE temperature 50℃, bath ratio 1:18, H2SO4 0.8 ml/L are the optimum parameters, MAE time 50 min, MAE temperature 99℃, BaO2 0.42 g/L, NaOH 9.9 g·L-1,H2O2 9.5 g·L-1,bath ratio 1:18 are the optimum parameters, the MAE combined alkali-H2O2 one-bath degumming which can be employed to the hemp fibers to remove non-cellulosic compounds, separate hemp fibres from their bundles.