ABSTRACT
Objective@#To study the effect of activated carbon on the purification of formaldehyde in the clean workshop return air purification device and its influencing factors.@*Methods@#From May to June 2018, choosed 4 different commercial activated carbons (bamboo charcoal, 1-3 mm, 3-5 mm; coconut shell charcoal, 6-12 mesh, 8-16 mesh) to make 5 types of activated carbon purification net. In the simulated clean plant laboratory, the detection of occupational disease hazards was used to test the purification effect of different types of activated carbon purification nets on formaldehyde.@*Results@#The purification effect of different types of activated carbon increased with the prolongation of purification time, and the difference was statistically significant (P<0.05) . Compared with other types of activated carbon, coconut shell charcoal (8-16 mesh, double layer) had the best purification effect, 15 min and 30 min purification efficiency was 58.72% and 85.20% respectively, and the difference was statistically significant (P<0.05) . The purification effect of double-layer coconut shell charcoal was better than single layer (P<0.05) . The purification effect of double-layer coconut shell charcoal (8-16 mesh) was better than double-layer coconut shell charcoal (6-12 mesh) , the difference was statistically significant (P<0.05) . Coconut shell charcoal (8-16 mesh, double layer) had better purification effect than bamboo charcoal (P<0.05) .@*Conclusion@#Different specific surface area, particle size, and thickness of activated carbon have a certain effect on the purification effect of formaldehyde, and its selection has a certain significance in improving the occupational health protection level in the clean plant, solving the safe use of return air and reducing energy consumption.
ABSTRACT
Objective The separation and purification of anthocyanin from blueberry was studied to determine the optimum purification conditions. Methods Static adsorption and desorption analytical test was conducted to screen the best macroporous resin from HPD-600, HPD-100A, DM130, D4020, and D3520 for purification of anthocyanins from blueberry. Effects of the sample liquid concentration, pH, adsorption flow rate, eluent ethanol concentration, eluent ethanol amount, and elution flow rate were investigated through dynamic adsorption-desorption test by single factor and orthogonal experiments. Results D3520 resin was the most effective resin for adsorption and desorption of anthocyanins from blueberry, when the amount of macroporous resin (g) and the amount of anthocyanin from blueberry (mL) was 1:5. The optimal conditions were as follows: The concentration of sample was 1.0 mg/mL, adsorption flow rate was 2.0 mL/min, and sample solution pH value was 3. Under the optimal conditions, eluent ethanol concentration 70%, elution flow rate 2.0 mL/min, eluent ethanol amount 60 mL, and the adsorption rate and desorption rate can reach 92.82% and 91.58% respectively. Conclusion The color value of purified products under the optimized conditions was increased by 11 times; The purity fraction of anthocyanin was 96.17% and the purity was increased by 5 times; And the yield of anthocyanin was 14.271%. This process effectively improves the efficiency of anthocyanin from blueberry purification, which is suitable for the future production of anthocyanin from blueberry.