Intensified bioleaching of a spent Co-Mo catalyst through the addition of extracellular polymeric substances (EPSs) and its mechanism exploration.

The extraction and recovery of valuable metals from various spent catalysts via bioleaching represents a green, low-carbon and eco-friendly process. However, the pulp density of spent catalysts is usually 1.0% or lower owing to their toxicity, denoting low process capacity and poor practical potential. In this study, an intensified bioleaching strategy was used for the first time to promote the release efficiencies of both Co and Mo from a spent Co-Mo catalyst at a high pulp density of 10% by supplementing extracellular polymeric substances (EPSs). The results showed that the addition of 0.6 g L-1 EPSs harvested a maximum release of 73.6% for Co and 72.5% for Mo after 9 days of contact, with an evident elevation of 22.6% for Co and 24.4% for Mo, in contrast to no addition, respectively. The added EPS not only promoted the growth of plankton cells to produce more active molecules but also boosted the adhesion of leaching cells to the spent catalyst to form stable aggregates. Moreover, the resulting aggregates allowed for the gathering and confinement of the active small molecules, including Fe3+ and Fe2+, inside the micro-areas between the spent catalysts and the cells for quick electronic transfer as an interface oxidation/reduction reaction to free both Co and Mo from the spent catalyst.

Facile manufacture of high-purity CuSO4 from waste Cu-containing paint residue using combined processes of H2SO4 leaching and extraction stripping.

Waste copper-containing paint residue (WCPR) represents a typical hazardous waste containing both toxic organic substances and toxic heavy metals, but there are few reports on the recycling of heavy metals. The recovery of Cu from WCPR by H2SO4 leaching-extraction-stripping has the advantages of eco-friendliness, simplicity of operation, and high value-added product. The results show that under the optimal conditions, the leaching rate of Cu in WCPR is 94.31% (18.02 g/L), while the extraction and stripping rates of Cu in the leaching solution are 99.46 and 95.32%, respectively. Due to the high concentration of Cu2+ with fewer impurities in the stripping solution, the stripping solution is heated, evaporated, cooled, and crystallized to successfully produce high-purity dark blue CuSO4 crystal, accomplishing the high-value recycling of Cu in WCPR. In addition, the leach residue of WCPR contains acrylic resin and SiO2, which can be used in cement kilns for incineration, thus realizing the overall recycling and utilization of WCPR.

Rapid and efficient extraction of Zn from wasted Zn-rich paint residue by indirect bioleaching and successive production of high-purity ZnCO3/ZnO by precipitation.

Waste zinc-rich paint residue (WZPR) represents a typical hazardous waste containing both toxic organic substances and heavy metals. The extraction of Zn from WZPR by traditional direct bioleaching has been attracting attention owing to its eco-friendliness, energy conservation and low cost. However, a long bioleaching time and a low Zn release cast a shadow on the reputed bioleaching. To shorten the bioleaching time, the spent medium (SM) process was first used to free Zn from WZPR in this study. The results showed that the SM process had a much higher performance in Zn extraction. Zn removals of 100% and 44.2% (8.6 g/L and 15.2 g/L in the released concentration) were gained within 24 h under pulp densities of 2.0% and 8.0%, respectively, being over 1000 times of the release performance of Zn by previously reported direct bioleaching. On the one hand, the biogenic H+ in SM attacks ZnO to liberate Zn (Ⅱ) via quick acid dissolution. On the other hand, the biogenic Fe3+ not only highly oxidizes Zn0 in WZPR to generate and release Zn2+ but also intensely hydrolyzes to produce H+ to attack ZnO for further dissolution of Zn2+. Both biogenic H+ and Fe3+ contribute to over 90% of Zn extraction as the leading indirect bioleaching mechanism. Due to the high concentration of released Zn2+ and fewer impurity, the bioleachate was used to successfully produce high-purity ZnCO3/ZnO using a simple precipitation, thus achieving the high-value recycling of Zn in WZPR.

Enhanced metal bioleaching mechanisms of extracellular polymeric substance for obsolete LiNixCoyMn1-x-yO2 at high pulp density.

Harmful chemicals present in electric vehicle Li-ion batteries (EV LIBs) can limit the pulp density of bioleaching processes using Acidithiobacillus sp. to 1.0% (w/v) or lower. The strong enhancing mechanisms of extracellular polymeric substances (EPS) on the bioleaching of metals from spent EV LIBs at high pulp density (4% w/v) were studied using bio-chemical, spectroscopic, surface structure imaging and bioleaching kinetic methods. Results demonstrated that the added EPS significantly improved bioleaching efficiency of Ni, Co and Mn improved by 42%, 40% and 44%, respectively. EPS addition boosted the growth of cells under adverse conditions to produce more biogenic H+ while Fe3+ and Fe2+ were adsorbed by the biopolymer. This increased Li extraction by acid dissolution and concentrated the Fe3+/Fe2+ cycle via non-contact mechanisms for the subsequent contact bioleaching of Ni, CO and Mn at the EV LIB-bacteria interface. During the leaching process, added EPS improved adhesion of the bacterial cells to the EV LIBs, and the resultant strong interfacial reactions promoted bioleaching of the target metals. Hence, a combination of non-contact and contact mechanisms initiated by the addition of EPS enhanced the bioleaching of spent EV LIBs at high pulp density.

Indirect bioleaching recovery of valuable metals from electroplating sludge and optimization of various parameters using response surface methodology (RSM).

Electroplating sludge contains amounts of valuable/toxic metals as a typical hazardous solid waste, but existing technology is hard to simultaneously gain the high recovery of valuable metals and its convert into general solid waste. In this study, indirect bioleaching process was optimized by using RSM for high recovery of four valuable metals (Ni, Cu, Zn and Cr) from electroplating sludge and its shift into general waste. The results showed that the maximum leaching rate respectively was 100% for Ni, 96.5% for Cu, 100% for Zn and 76.1% for Cr at the optimal conditions. In particular, bioleaching saw a much better performance than H2SO4 leaching in removal of highly toxic Cr (76.1% vs. 30.2%). The extraction efficiency of Cr by H2SO4 leaching sharply rose to 72.6% in the presence of 9.0 g/L Fe3+, suggesting that Fe3+ played an important role in the bioleaching of Cr. Based on bioleaching dynamics analysis, it was speculated that Fe3+ passes through the solid shell and enter inside the sludge to attack Cr assisting by extracellular polymeric substances (EPS), leading to high extraction and low residue of Cr. Meanwhile, due to high-efficient release and removal of valuable/toxic metals by bioleaching, the bioleached residues successfully degraded into general based on TCLP test and can be reused as construction material safely.

Controlled Biosynthesis of ZnCdS Quantum Dots with Visible-Light-Driven Photocatalytic Hydrogen Production Activity.

The development of visible-light-responsive photocatalysts with high efficiency, stability, and eco-friendly nature is beneficial to the large-scale application of solar hydrogen production. In this work, the production of biosynthetic ternary ZnCdS photocatalysts (Eg = 2.35-2.72 eV) by sulfate-reducing bacteria (SRB) under mild conditions was carried out for the first time. The huge amount of biogenic S2- and inherent extracellular proteins (EPs) secreted by SRB are important components of rapid extracellular biosynthesis. The ternary ZnCdS QDs at different molar ratios of Zn2+and Cd2+ from 15:1 to 1:1 were monodisperse spheres with good crystallinity and average crystallite size of 6.12 nm, independent of the molar ratio of Cd2+ to Zn2+. All the ZnCdS QDs had remarkable photocatalytic activity and stability for hydrogen evolution under visible light, without noble metal cocatalysts. Especially, ZnCdS QDs at Zn/Cd = 3:1 showed the highest H2 production activity of 3.752 mmol·h-1·g-1. This excellent performance was due to the high absorption of visible light, the high specific surface area, and the lower recombination rate between photoexcited electrons and holes. The adhered inherent EPs on the ZnCdS QDs slowed down the photocorrosion and improved the stability in photocatalytic hydrogen evolution. This study provides a new direction for solar hydrogen production.

Generation behavior of extracellular polymeric substances and its correlation with extraction efficiency of valuable metals and change of process parameters during bioleaching of spent petroleum catalyst.

The vital functions of extracellular polymeric substances (EPS) have been well recognized in bioleaching of sulfide ores. However, no report is available about the role of EPS in bioleaching of spent catalyst. To completely and deeply understand the functions of EPS in bioleaching of spent catalyst, the generation behavior of EPS at various pulp densities during bioleaching was characterized by three-dimensional excitation-emission matrix (3DEEM), and its relevance with bioleaching performance and process parameters were analyzed using mathematical means. The results showed that the EPS contain humus-like substances as main component (>70%) and protein-like substances as minor component (<30%). Both total EPS and humus-like substances mainly keep growing over the whole duration of bioleaching at low pulp density of 5.0% or lower; whereas total EPS and humus-like fraction keep declining at high pulp density of 7.5% or higher. Among the total EPS and its components, humus-like substances only have a positive significant correlation with bioleaching efficiencies of both Co and Mo and affect bioleaching process more greatly due to greater correlation coefficient. Biofilm appears at the spent catalyst surface under 2.5% of pulp density mediated by EPS while no biofilm occurs at 10% of pulp density due to shortage of EPS, accounting for the great difference in bioleaching efficiencies between high and low pulp densities which are 48.3% for Mo and 50.0% for Co at 10% of pulp density as well as 75.9% for Mo and 78.8% for Co at 2.5% of pulp density, respectively.

Quick extracellular biosynthesis of low-cadmium Zn x Cd1-x S quantum dots with full-visible-region tuneable high fluorescence and its application potential assessment in cell imaging.

The biosynthesis of metal nanoparticles/QDs has been universally recognized as environmentally sound and energy-saving, generating less pollution and having good biocompatibility, which is most needed in biological and medical fields. In the arena of chemical routes, however, biosynthesis has long been criticized for its low productivity, time-consuming process, and poor control over size, shape and crystallinity, keeping the much-needed technology away from practical application. In this work, a rapid and extracellular biosynthesis of multi-colour ternary Zn x Cd1-x S QDs by a mixed sulfate-reducing bacteria (SRB)-derived supernatant was carried out for the first time to solve the problems plaguing this field of biosynthesis. The results showed that about 3.5 g L-1 of Zn x Cd1-x S QDs with size of 3.50-4.64 nm were achieved within 30 minutes. The PL emission wavelength of Zn x Cd1-x S QDs increased from 450 to 590 nm to yield multicolor QDs by altering the molar ratio of Cd2+ to Zn2+. The SRB-biogenic Zn x Cd1-x S QDs have high stability in gastric acid and at high temperature, as well as excellent biocompatibility and biosafety, successfully entering growing HeLa cells and labelling them without detectable harm to cells. The SRB-secreted peculiar extracellular proteins (EPs) play a decisive function in the time-saving, high-yield biosynthesis of PL-tuned multicolor QDs, which cover an abnormally high concentration of acidic amino acids to provide tremendous negatively charged sites for the absorption of Cd2+/Zn2+ for rapid nucleation and biosynthesis. The strongly electrostatic connection between the QDs and the EPs and the increasing amount of EPs attached to the QDs in response to the increase of Cd2+ concentration account for their high stability and excellent biocompatibility.

Improved bioleaching of copper and zinc from brake pad waste by low-temperature thermal pretreatment and its mechanisms.

A considerable amount of brake pad waste which is composed of phenolic resin and a variety of toxic heavy metals is produced both in China and around the world owing to the flourishing automobile industry. The safe, low cost and eco-sound bioleaching was utilized to extract the valuable metals Cu and Zn from the waste. The results showed that although bioleaching is more efficient in the extraction of Cu and Zn than the chemical counterpart, rather low bioleaching yields of 34% for Cu and 72% for Zn were obtained because of the complicated components and refractory nature of the waste. However, a low-temperature thermal pretreatment at 400 °C notably lifted the bioleaching efficiencies of Cu and Zn to 98% and nearly 100%, respectively. The thermal treatment removed the oil substances, transformed the acid insoluble Cu0 into acid soluble CuO and destroyed the chelation/complexation of the phenolic resin to loose Cu and Zn, promoting bioleaching performance of Cu and Zn. The combined processes of low-temperature thermal pretreatment and bioleaching is totally qualified for the extraction of Cu and Zn from the refractory waste.

High-Yield Extracellular Biosynthesis of ZnS Quantum Dots through a Unique Molecular Mediation Mechanism by the Peculiar Extracellular Proteins Secreted by a Mixed Sulfate Reducing Bacteria.

This work describes a high-yield extracellular biosynthesis of ZnS QDs via a unique molecular mediation mechanism driven by the mixed sulfate reducing bacteria (SRB). The mixed SRB have obtained the highest ever ZnS QD biosynthesis rate of 35.0-45.0 g/(L·month). The biogenic ZnS QDs with an average crystallite size (ACS) of 6.5 nm have greater PL activity and better uniformity than that of a chemical route. Peculiar extracellular proteins (EPs) with molecular weights of approximately 65 and 14 kDa specially adhere to the ZnS QDs, which cover extraordinarily high contents of acidic amino acids (14.0 mol % Glu and 13.0 mol % Asp) and of nonpolar amino acids (12.0 mol % Ala, 11.0 mol % Gly, and 7.0 mol % Phe), for novel molecular mediation. The vast amount of negative charges in Glu and Asp guides the strong absorption between the EPs and Zn2+ via electrostatic attraction to reach a maximum absorption capacity of 745.9 mg/g within 2.0 h, motivating large and rapid nucleation as the first step of biosynthesis. Meanwhile, bridging and interlinkage occur inside the EPs or between the EPs via hydrophobic interactions dominated by the nonpolar amino acids, resulting in the formation of massive microcavities to control and restrict the growth of ZnS QDs as a template. The novel molecular mediation mechanism triggered by the peculiar EPs with an extraordinary amino acid composition and structure accounts for the high-yield biosynthesis of ZnS QDs. The mixed SRB have also successfully fabricated other metal sulfide QDs, including PbS, CuS, and CdS, through the novel molecular mediation.

Functional exploration of extracellular polymeric substances (EPS) in the bioleaching of obsolete electric vehicle LiNixCoyMn1-x-yO2 Li-ion batteries.

As a fairly new concept, the recovery of valuable metals from urban mining by using bioleaching has become a hotspot. However, the function of extracellular polymeric substances (EPS) in the bioleaching of urban mining gains little attention. The current study used spent EV LIBs to represent urban mining products and systematically explored the function and role of EPS in the attachment of cells to the cathodes, formation of aggregates (cell-EPS-cathode), variation in the electrical and surface properties of the aggregates, concentration of both Fe2+ and Fe3+ surrounding the aggregates, electron transfer inside the aggregates and metals released from the aggregates. The results indicated that a strong adhesion of cells to the cathodes occurs mediated by EPS via both hydrophobic force as a main role and electrostatic force as a minor role. Second, the EPS not only adsorb Fe3+ but also more strongly adsorb Fe2+ to concentrate the Fe2+/Fe3+ cycle inside the aggregates, witnessing stronger reductive attack on the high valence state of metals as a contact reductive mechanism. Third, the retention or addition of EPS elevated the electronic potential and reduced the electronic resistance to lift the corrosion electric current, thereby boosting the electron transfer and metal dissolution.

Controllable biosynthesis of high-purity lead-sulfide (PbS) nanocrystals by regulating the concentration of polyethylene glycol in microbial system.

We demonstrated a simple biological method to explore the controllable synthesize of high-purity PbS nanocrystals by regulating the concentration of polyethylene glycol in microbial system. The biogenic H2S produced via the reduction of sulfate precipitated Pb2+ ions as sulfide extracellularly, and the optimal removal rate of Pb2+ ions is up to 96.7 % in 2 weeks. The characterization results showed that PbS nanocuboids with a particle size 50 × 50 × 100 nm obtained from Case A with 4 mM polyethylene glycol as a dispersant, and can completely degrade methylene blue from solution within 20 h; PbS nanosheets with a thickness size ca. 10 nm attained from Case B with 12 mM polyethylene glycol, and it can degrade 61.6 % dye within 24 h; PbS nanoparticles with a uniform diameter of ca. 60 nm formed from Case C with 20 mM polyethylene glycol, only degrade 14.1 % dye within 24 h. It is interesting that the factor affecting their catalytic activities is not the specific surface area, but the number of [200] crystal plane. This work not only displayed a simple synthetic method to control the morphology of PbS nanocrystals in microbial system, but also provided an economic and environmentally friendly approach for resourceful treatment and efficient bioremediation of wastewater-containing heavy metal.

Extracellular synthesis of cuprous selenide nanospheres by a biological-chemical coupling reduction process in an anaerobic microbial system.

Biosynthesis of metal nanoparticles represents a clean, eco-friendly and sustainable "green chemistry" engineering. Lately, a number of metal selenides were successfully synthesized by biological methods. Here, cuprous selenide (Cu2 Se) nanospheres were prepared under mild conditions by a novel biological-chemical coupling reduction process. The simple process takes place between EDTA-Cu and Na2 SeO3 in presence of an alkaline solution containing NaBH4 and a selenite-reducing bacteria, Pantoea agglomerans. It is noteworthy that the isolated Pantoea agglomerans and Cu+ ions, where the latter are obtained from reducing Cu2+ ions by NaBH4 , play a key role, and Cu+ ions not only can promote the generation of Se2- ions as a catalyst, but also can react with Se2- ions to form Cu2 Se. XRD pattern, SEM, and TEM images indicated that Cu2 Se nanoparticles were tetragonal crystal structure and the nanospheres diameter were about 100 nm. EDX, UV-vis, and FTIR spectra show that the biosynthesized Cu2 Se nanospheres are wrapped by protein and have a better stability. This work first proposes a new biosynthesis mechanism, and has important reference value for biological preparation of metal selenide nanomaterials. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1264-1270, 2016.

Complete mitochondrial genome of freshwater shark Wallago attu (Bloch & Schneider) from Indus River Sindh, Pakistan.

Complete mitochondrial genome of fresh water giant catfish, Wallago attu, was isolated by LA PCR (TakaRa LAtaq, Dalian, China); and sequenced by Sanger's method to obtain the complete mitochondrial genome. The complete mitogenome was 15,639 bp in length and contains 13 typical vertebrate protein-coding genes, 2 rRNA and 22 tRNA genes. The whole genome base composition was estimated to be 31.17% A, 28.15% C, 15.55% G and 25.12% T. The complete mitochondrial genome of catfish, W. attu, provides the fundamental tools for genetic breeding.

Metallic ions catalysis for improving bioleaching yield of Zn and Mn from spent Zn-Mn batteries at high pulp density of 10.

Bioleaching of spent batteries was often conducted at pulp density of 1.0% or lower. In this work, metallic ions catalytic bioleaching was used for release Zn and Mn from spent ZMBs at 10% of pulp density. The results showed only Cu(2+) improved mobilization of Zn and Mn from the spent batteries among tested four metallic ions. When Cu(2+) content increased from 0 to 0.8 g/L, the maximum release efficiency elevated from 47.7% to 62.5% for Zn and from 30.9% to 62.4% for Mn, respectively. The Cu(2+) catalysis boosted bioleaching of resistant hetaerolite through forming a possible intermediate CuMn2O4 which was subject to be attacked by Fe(3+) based on a cycle of Fe(3+)/Fe(2+). However, poor growth of cells, formation of KFe3(SO4)2(OH)6 and its possible blockage between cells and energy matters destroyed the cycle of Fe(3+)/Fe(2+), stopping bioleaching of hetaerolite. The chemical reaction controlled model fitted best for describing Cu(2+) catalytic bioleaching of spent ZMBs.

Bioleaching mechanism of Zn, Pb, In, Ag, Cd and As from Pb/Zn smelting slag by autotrophic bacteria.

A few studies have focused on release of valuable/toxic metals from Pb/Zn smelting slag by heterotrophic bioleaching using expensive yeast extract as an energy source. The high leaching cost greatly limits the practical potential of the method. In this work, autotrophic bioleaching using cheap sulfur or/and pyrite as energy matter was firstly applied to tackle the smelting slag and the bioleaching mechanisms were explained. The results indicated autotrophic bioleaching can solubilize valuable/toxic metals from slag, yielding maximum extraction efficiencies of 90% for Zn, 86% for Cd and 71% for In, although the extraction efficiencies of Pb, As and Ag were poor. The bioleaching performance of Zn, Cd and Pb was independent of leaching system, and leaching mechanism was acid dissolution. A maximum efficiency of 25% for As was achieved by acid dissolution in sulfursulfur oxidizing bacteria (S-SOB), but the formation of FeAsO4 reduced extraction efficiency in mixed energy source - mixed culture (MS-MC). Combined works of acid dissolution and Fe(3+) oxidation in MS-MC was responsible for the highest extraction efficiency of 71% for In. Ag was present in the slag as refractory AgPb4(AsO4)3 and AgFe2S3, so extraction did not occur.

Biosynthesis of high-purity γ-MnS nanoparticle by newly isolated Clostridiaceae sp. and its properties characterization.

MnS is a p-type semiconductor with both antiferromagnetism and wide band gap, endowing it potential applications for short wavelength optoelectronic devices, solar cells and luminescent materials. Despite successful biosynthesis of nano CdS, PbS and ZnS with extremely low solubility product, there have been no reports available on biosynthesis of nano MnS so far because both PO4(3-) and OH(-) negatively disturb reaction between Mn(2+) and S(2-) through forming Mn3(PO4)2 and Mn(OH)2 as undesirable impurities. In this work, high-purity MnS nanocrystals were synthesized in presence of newly isolated Clostridiaceae sp. through strictly controlling pH value and PO4(3-) dose for the first time. The results showed that hexagonal-shaped γ-MnS with a diameter of 2-3 µm and a thickness of 200-300 nm was obtained by biosynthesis at 0.014 g/L PO4(3-) dose and pH 5.8. The hexagonal-shaped particle possessed dense and uniform texture. The γ-MnS had an obvious absorption peak at 325 nm and an emission peak at 435 nm as well as paramagnetic property with a coercivity of 52.91 Oe and a retentivity of 4.37 × 10(-3) emu/g at ambient temperature. The studies demonstrated that biosynthesis was qualified for preparation of nano metal sulfites with relatively high solubility product like MnS, widening its application spectrum.

QTL mapping for economically important traits of common carp (Cyprinus carpio L.).

Quantitative trait loci (QTL) were analyzed for three economically important traits, i.e., body weight (BW), body length (BL), and body thickness (BT), in an F1 family of common carp holding the 190 progeny. A genetic linkage map spanning 3,301 cM in 50 linkage groups with 627 markers and an average distance of 5.6 cM was utilized for QTL mapping. Sixteen QTLs associated with all three growth-related traits were scattered across ten linkage groups, LG6, LG10, LG17, LG19, LG25, LG27, LG28, LG29, LG30, and LG39. Six QTLs for BW and five each for BL and BT explained phenotypic variance in the range 17.0-32.1%. All the nearest markers of QTLs were found to be significantly (p ≤ 0.05) related with the trait. Among these QTLs, a total of four, two (qBW30 and qBW39) related with BW, one (qBL39) associated with BL, and one (qBT29) related to BT, were found to be the major QTLs with a phenotypic variance of >20%. qBW30 and qBW39 with the nearest markers HLJ1691 and HLJ1843, respectively, show significant values of 0.0038 and 0.0031, correspondingly. QTLs qBL39 and qBT29 were found to have significant values of 0.0047 and 0.0015, respectively. Three QTLs (qBW27, qBW30, qBW39) of BW, two for BL (qBL19, qBL39), and two for BT (qBT6, qBT25) found in this study were similar to populations with different genetic backgrounds. In this study, the genomic region controlling economically important traits were located. These genomic regions will be the major sources for the discovery of important genes and pathways associated with growth-related traits in common carp.

Process controls for improving bioleaching performance of both Li and Co from spent lithium ion batteries at high pulp density and its thermodynamics and kinetics exploration.

Release of Co and Li from spent lithium ion batteries (LIBs) by bioleaching has attracted growing attentions. However, the pulp density was only 1% or lower, meaning that a huge quantity of media was required for bioleaching. In this work, bioleaching behavior of the spent LIBs at pulp densities ranging from 1% to 4% was investigated and process controls to improve bioleaching performance at pulp density of 2% were explored. The results showed that the pulp density exerted a considerable influence on leaching performance of Co and Li. The bioleaching efficiency decreased respectively from 52% to 10% for Co and from 80% to 37% for Li when pulp density rose from 1% to 4%. However, the maximum extraction efficiency of 89% for Li and 72% for Co was obtained at pulp density of 2% by process controls. Bioleaching of the spent LIBs has much greater potential to occur than traditional chemical leaching based on thermodynamics analysis. The product layer diffusion model described best bioleaching behavior of Co and Li.

Controllable extracellular biosynthesis of bismuth sulfide nanostructure by sulfate-reducing bacteria in water-oil two-phase system.

Due to strong hydrolysis of Bi(3+) as precursor in aqueous media, there are no reports on biosynthesis of bismuth sulfide (Bi2 S3 ) nanomaterials. In this work, the water-oil two-phase system was used to biosynthesize the Bi2 S3 nanomaterials based on the coupling reaction of biological reduction and chemical precipitation process for the first time. The results showed that the water-oil two-phase system successfully eliminated hydrolysis of the Bi(3+) and controllably and extracellularly fabricated the Bi2 S3 crystal with high purity. The nanorods with diameter of about 100 nm and length of about 1.0 µm were attained under high dose of lactic acid and SO4 (2-) ; while low dose obtained the nanobundles consisted of nanoneedles with tip diameter of 10-20 nm and length of about 5.0-10.0 µm. The Bi2 S3 nanorods as photocatalyst almost completely degraded methylene blue from solution within 12 h; whereas the Bi2 S3 nanobundles removed about 87% of the dye. The amount of the Bi2 S3 nanorods decreased by 48% due to photocorrosion, whereas 52% with the nanobundles. The Bi2 S3 nanorods had relatively higher photocatalysis activity and slightly stronger photocorrosion resistance than the Bi2 S3 nanobundles.