Extraction and charactrisation of humic acid from different organic wastes and its physico-chemical properties

Abstract

A study on characterization and extraction of humic acid collected from various agro-industrial and agricultural organic wastes from different locations viz., cocopeat, coffee pulp, pressmud, biofuel waste, distillery biocompost, sewage sludge, poultry manure, vermicompost, urban compost and farm yard manure (FYM). Results revel that physical properties such as bulk density and water holding capacity of different organic wastes ranged from 0.22 Mg m -3 (85.50 %) in coco peat to 0.69 Mg m -3 (40.21%) of biofuel waste. Chemical properties like pH of poultry manure (pH 8.32) were alkaline in nature and biofuel waste (pH 5.28) slightly acidic in nature. Electrical conductivity was high 1.89 dSm -1 in coffee pulp followed by FYM 1.50 dS m -1 . Organic carbon content was higher (40.99%) in biofuel waste. While it was lowest (14.13%) in sewage sludge. With respect to major and secondary nutrients poultry manure recorded higher total N, P, K and Ca (2.85, 1.56, 1.92 and 3.89 %) and iron, manganese, copper and zinc(3850, 541.30, 76 and 476 mg kg -1 respectively). Higher recovery of humic and fulvic acid, (8.92 and 4.21 %, respectively) was recorded in press mud and lowest was in coco peat with 3.43 and 2.45 per cent, respectively. Elemental composition (CHNO) of humic acid extracted from poultry manure had higher N (6.01 %) followed by pressmud and coffee pulp. Higher C (61.04 %) and H (8.89%) were recorded in biofuel waste and O (52.31 %) was higher in sewage sludge. Carboxyl (6.08 meq g -1 ), phenolic hydroxyl (1.94 meq g -1 ) groups and total acidity (8.02 meq g -1 ) was higher in poultry manure followed by pressmud and coffee pulp. However, lower content of carboxyl (2.84 meq g -1 ) phenolic hydroxyl group (1.32 meq g -1 ) and total acidity (4.16 meq g -1 ) was observed in biofuel waste. Slightly higher concentration of nickel (21.8 mg kg -1 ) and chromium (17 mg kg -1 ) was observed in humic acid of sewage sludge.

Extraction of Humic Acid from Agricultural Crop Residues Conditioned with Cow Dung, Compost from Landfill and Human Waste

“…The low value of E4/E6 obtained for LC is due to the microbial activity which takes place in long period, this result to high degree of humification, aromatic condensation and molecular weight or size in the range of 5,000 to 100,000 Dalton [11]. While the high value ratio of E4/E6 obtained for HW shows high rate of aliphatic structure and low degree of aromatic [18,22].…”

“…This is followed by B sample which has E4/E6 ratio of 4.641, this is also followed by sample A which has 4.959 value of E4/E6, A also followed by C which has E4/E6 value of 5.56 and the last is the human waste (HW) with E4/E6 ratio of 6.51. HW with high E4/E6 ratio of 6.51 is due to this value is out range of E4/E6 ratio of 3.5-5.9.The low value of E4/E6 obtained for LC is due to the microbial activity which takes place in long period, this result to high degree of humification, aromatic condensation and molecular weight or size in the range of 5,000 to 100,000 Dalton[11]. While the high value ratio of E4/E6 obtained for HW shows high rate of aliphatic structure and low degree of aromatic[18,22].…”

“…As waste water cease from faces, faces started to be dried with sunlight that pass through the white aluminium sheet of separating house. When faces are dried above sands are stored in storage house (11) for ready being used as organic fertilizer or being used in extraction of humic acid.…”

“…Humic conditioning are most obtained from fossil sources such as leonardite, peats, manures, coals and other sources [10], but other sources such as, landfill compost, agricultural residues or livestock residue like cow dung and faces may be envisaged. Humic acid heterogeneity is favoured by method used to extract, origin, types of humic substances source and nature of the chemical extractive agent [11]. Humic acid or humic substances form an integral part of the ecosystem as they play an important role in global cycling and availability of nutrients, carbon content, water holding capacity [12], and soil detoxication [6].…”

Humic Acid: A Promising and Green Bioorganic Catalyst in Organic Syntheses

“…In some cases after extraction, the HA is added into HCl solution to remove mineral impurities. [10][11][12][13][14][15][16][17][18][19][20][21] Moreover, the HA is now available commercially. Apart from the applications in medicine, cosmetics and agriculture field, first time Klavins et al [22a] in 2001 introduced HA in condensation and Michael addition reactions by activating the carbonyl groups via protonation.…”