Application of biochar produced from wood and seaweed for the removal of dye in wastewater

Transcription

1 Application of biochar produced from wood and seaweed for the removal of dye in wastewater Mi Nam Lee and Seung Han Woo* Hanbat National University, Korea 2 nd FORBIOM Workshop Potentials of Biochar to Mitigate Climate Change

2 Outline 1 2 Application for Corn Cultivation 1

3 Biomass Resources Biomass Terrestrial Aquatic 1 st generation 2 nd generation 3 rd generation Agriculture crops Lignocellulosic biomass Microalgae Macroalgae 2

4 Energy Production from Biomass Agriculture Crops Lignocellulosic Algae Production interval Production yield (ton/ha) Energy conversion 1~2/yr >~8 yrs 4~6/yr ~35% 20~25% > 45% 3

5 Types of Macroalgae Brown Algae Red Algae Sea mustard Kelp Purple laver Sea string Agar Green Algae Hijikia Gulfweed Gom Pi Green laver Greyblue Spicebush Seaweed fulvescens 4

6 Objectives Application for dye adsorption Textile industries discharge large amounts of colored wastewater containing various dyes, some of which are mutagenic and carcinogenic to human beings. The adsorption of Congo red and Methylene blue using biochars produced with four different biomass sources was investigated. Application for crop cultivation Mostly, it is known that biochar augmentation increases crop yield due to water and nutrient retention, etc. However, it has sometimes been reported to have negative effects on crop yield. In order to know the effect of the seaweed biochars on crop growth, corn was cultivated in the field with or without the biochars and/or compost fertilizer. 6

7 1 7

8 Pyrolysis System Bio-gas N2 Bio-oil Bio-char 8

9 Biomass Materials Drying (120, 100 h) Oak tree Bamboo Drying, Grinding Kelp Green laver Pyrolysis conditions Temperature: 200, 300, 400, 500 o C Heating rate: 3, 6, 9 min Holding time: 0, 20, 60 min N 2 flow rate: 100 ml/min 9

10 Effect of Temperature Biooil Biochar Biogas Yield (%) Temperature ( o C) Fig. 1. The effect of temperature on the yield of pyrolysis prod ucts with oak tree. 10

11 Yields of Pyrolysis Products Yield (%) Bamboo Oak tree Kelp Green laver 10 0 biooil biochar biogas Fig. 2. The yield of pyrolysis products with different biomass (400 o C, 9 o C/min, 60 min). 11

12 FE-SEM Images Oak tree Bamboo Kelp Green laver Fig. 3. FE-SEM images of the surfaces of biochars made from different biomass sources (400 oc, 9 oc/min, 60 min). 12

13 CHONS Analysis Table 1. Elemental analysis for various biochars (400 o C, 9 o C/min, 60 min) N (%) C (%) H (%) S (%) O (%) Oak tree ND Bamboo ND Kelp Green laver

14 Target Dye Chemicals Anionic Dye Cationic Dye Congo red Methylene blue 14

15 Adsorption Experiments Congo red solution 10 ml Methylene blue solution 10 ml Bio-char (0.2 g, 300~500 µm) Shaking (25, 125 rpm, 24 h) Spectrophotometer (DR5000, HACH) λ max : 497 nm (congo red) λ max : 665 nm (methylene blue) 15

16 Isotherm Study (Congo Red) Congo red adsorption (Oak tree) Congo Red adsorption (Bamboo) 50 Experimental data Langmuir isotherm Freundlich isotherm Experimental data Langmuir isotherm Freundlich isotherm q e (mg/g) q e (mg/g) C e (mg/l) C e (mg/l) (a) Fig. 4. Isotherms for the adsorption of congo red with various biochar sorbents. (b) 16

17 Isotherm Study (Congo Red) Congo red adsorption (Kelp) Congo Red adsorption (Green laver) Experimental data Langmuir isotherm Freundlich isotherm Experimental data Langmuir isotherm Freundlich isotherm q e (mg/g) 40 q e (mg/g) C e (mg/l) C e (mg/l) (c) (d) Fig. 4. Isotherms for the adsorption of congo red with various biochar sorbents. 17

18 Long-term Adsorption (Congo Red) mg/l 1000 mg/l Fig. 5. Long-term adsorption of congo red with various sorbents. qe (mg/g) Oak tree 5 0 Kelp Day mg/l 500 mg/l 1000 mg/l mg/l 500 mg/l 1000 mg/l Activated carbon qe (mg/g) qe (mg/g) Day Day 18

19 Isotherm Study (Methylene Blue) Methylene blue adsorption (Oak tree) Methylene blue adsorption (kelp) Experimental data Langmuir isotherm Freundlich isotherm Experimental data Langmuir isotherm Freundlich isotherm q e (mg/g) q e (mg/g) C e (mg/l) C e (mg/l) (a) (b) Fig. 6. Isotherms for the adsorption of methylene blue with various biochar sorbents. 19

20 Isotherm Parameters Isotherm model Langmuir isotherm q e Freundlich isotherm q qmax K 1 K e K F L C C C L e 1/ n e e biochar sorbent Dye parameter value k L (dm 3 mg -1 ) q m (mg g -1 ) R 2 Oak tree Congo red Bamboo Congo red Kelp Congo red Green laver Congo red Oak tree Methylene Blue Kelp Methylene Blue K F (dm 3 g -1 ) 1/n R 2 Oak tree Congo red Bamboo Congo red Kelp Congo red Green laver Congo red Oak tree Methylene Blue Kelp Methylene Blue

21 Summary The highest production yield was achieved with green laver and kelp for biochar and biooil, respectively. In case of oak tree, many pores were formed during pyrolysis, but not in case of seaweed biomass. The carbon content was much lower in seaweed biomass than wood biomass, while nitrogen and sulfur content were higher in seaweed biomass. The biochar of kelp and oak tree showed higher Langmuir adsorption capacity for congo red compared to that of bamboo and green laver. In case of methylene blue, kelp biochar showed much higher adsorption capacity (243 mg/g) than oak tree biochar. Kelp biochar showed slow but high adsorption capacity in the long-term adsorption. The biochars, more preferably seaweed biochars, could be effective and low cost adsorbents for the removal of anionic or cationic dyes from wastewater. 21

22 2 Application for Corn Cultivation 22

23 Production of Biochar (a) (b) Biomass resource: (a) Fir pellet 500 g, (b) kelp 500 g Pyrolysis system: Traditional can (40 L), heating for 3 hrs 23

24 CHON Analysis Table 1. Elemental analysis data of raw biomass and its biochar Biomass C H O N Others Fir wood pellet Fir biochar Kelp Kelp biochar

25 Element Concentration Table 2. Element concentration in biochars measured by ICP. The elements Ag, Be, Cd, Co, Cr, Li, Mo, Ni, Pb, Se, Si, W, and Zr were not found. Element Fir biochar Kelp biochar mg/kg RSD(%) mg/kg RSD(%) Al As B Ba Ca Cu Fe K Mg Mn Na P S Sr Ti V Zn

26 Corn Cultivation Biochar addition: The 20g of biochar powders after grinding was added with or without compost fertilizer sold in a local market. Planting: young tree of corn (10cm) Multiplicity: n = 4 Planting conditions: without compost (A), with compost (B), without biochar (1), with fir biochar (2), with kelp biochar (3) B3 B2 B1 A3 A2 A1 Biochar kelp fir X kelp fir X Compost O O O X X X 27

27 Effect of Biochar on Crop Yield 5d B3 B2 B1 A3 A2 A1 12d B3 B2 B1 A3 A2 A1 B3 B2 B1 A3 A2 A1 Biochar kelp fir X kelp fir X Compost O O O X X X 28

28 Effect of Biochar on Crop Yield 27d B3 B2 B1 A3 A2 A1 B3 B2 B1 A3 A2 A1 Biochar kelp fir X kelp fir X Compost O O O X X X 29

29 Effect of Biochar on Crop Yield 63d A1 A2 A3 B1 B2 B3 B3 B2 B1 A3 A2 A1 Biochar kelp fir X kelp fir X Compost O O O X X X 30

30 Effect of Biochar on Crop Yield 10 % Application rate (t/ha) 177 treatments sewage sludge (-28%) Acidic soil (14%) Large soil (10%) Large amount (39%) Poultry waste (28%) Jeffery et al., Agr. Ecosyst. Environ.,

31 Summary Biochar was positively effective but only when compost fertilizer was added together in the soil for the corn growth, which is reasonable because biochar plays a role in the retention of nutrients. Kelp seaweed biochar has lower carbon storing effects than woody biomass on the basis of the total weight of raw biomass. Kelp seaweed biochar showed significant inhibition of corn growth probably due to toxicity caused by higher contents of heavy metals. The toxic effect of kelp biochar was serious in the initial phase, but recovered at some extent with time, indicating soil minerals might have mitigated the toxicity. 32