Formic Acid Process Research Articles

Life cycle GHG emissions and economic viability of two levulinic acid production processes from biomass: A case study of Japan and Canada

We evaluated CO2 equivalent (CO2eq) greenhouse gas (GHG) emissions and minimum selling price of levulinic acid (LA) produced in two biomass-waste-based processes: the AlCl3/choline chloride (ChCl) process, and the formic acid (FA) process, with catalysts recycling. Six scenarios were synthesized to compare the performances of the two processes in Japan and Canada. In the AlCl3/ChCl process, the total GHG emission was 11.35–11.56 kg-CO2eq/kg-LA and those from the energy input to the pretreatment and ChCl production were 5.22 and 3.90 kg-CO2eq/kg-LA, respectively. In the FA process, the total GHG emission was 9.46–9.68 and 22.29–22.51 kg-CO2eq/kg-LA for 60 wt% and 80 wt% FA, respectively. The operational emissions for makeup FA input were 7.65 and 20.80 kg-CO2eq/kg-LA (60 wt% and 80 wt%, respectively), which accounted for more than 80% in all scenarios. The optimization of the product purge volume, FA concentration in the pretreatment, and FA production using biomass and/or renewable energy are critical parameters to reduce overall environmental impacts of the processes. The liquid content of the solid residue (moisture, water soluble organic matters, and catalyst) had insignificant influences on the GHG emission and minimum selling price. In the FA process, combustion of solid residue can compensate the GHG emissions from the reaction and separation units.

Innovative green approach for recovering Co2O3 nanoparticles and Li2CO3 from spent lithium-ion batteries

Although previous studies have obtained promising results for recovering valuable metals from spent LIBs at low temperatures using organic acids combined with reducing agents, additional chemicals such as H2O2, huge amounts of organic acids, and environmental protection remain challenges. In this study, a subcritical water (SCW) assisted diluted formic acid process was proposed as a green approach for recovering Co2O3 nanoparticles and Li2CO3 from spent LiCoO2 cathode materials without using any reducing agents. The effects of leaching parameters such as (H2O: HCOOH) ratio (v/v), temperature, reaction time, and liquid-solid ratio on the extraction of Li and Co have been carefully evaluated. The findings revealed that SCW-assisted (DFA) successfully leaches Li and Co from the spent LiCoO2 cathode materials of Li-ion batteries without using any assistance from reducing reagents. The solid materials were characterized by XRD, XPS, FT-IR, and SEM-EDS analyses. Meanwhile, the leaching liquor was analyzed by ICP-OES. More than 99% of Li and Co were effectively recovered from the spent LiCoO2 powder at 220 °C for 25 min, H2O: HCOOH ratio (v/v,) of 78:12 and a liquid-solid ratio of 25 mL/g. Further, the activation energy for Li was 24.15 KJ/mol, while that for Co was 31 KJ/mol. Finally, Co2O3 and Li2CO3 were successfully recovered from the leaching liquor by the precipitation and calcination methods after the separation steps. The overall findings suggested that SCW-assisted (DFA) could be an alternative method due to its low energy consumption, dual function properties at mild temperatures, low chemical input, and environmentally friendly.

Enhanced degradation of organic pollutants by MnCo2O4.5/formic acid process: Active species and mechanism

• The MnCo 2 O 4.5 /formic acid system led to high oxidation of Methyl Orange. • Mn(III) was found to be the active species for organic pollutant degradation. • The degradation rate of MO was 92.7% in 30 min. • This study might lead to a novel advanced oxidation technology. A system of MnCo 2 O 4.5 catalyst/formic acid is proposed for the degradation of methyl orange (MO). The degradation rate of MO reached 92.7% in MnCo 2 O 4.5 /formic acid process. The efficient degradation of MnCo 2 O 4.5 /formic acid system was based on oxidation by Mn(III).

Formic acid synthesis and utilization for solar energy storage through solar‐driven chloralkali process and fuel cells

AbstractThe objective of this work is to propose an integrated system for formic acid synthesis via photovoltaic (PV) assisted‐chloralkali process and clean power generation by the fuel cell. The initial step is to develop process flow diagrams and to apply heat integration techniques to conserve energy in the synthesis of formic acid and direct formic acid fuel cell (DFAFC). The proposed system forms formic acid from gaseous H2 produced from chloralkali unit and captured CO2. The electricity requirements of both PV‐assisted chloralkali and compression stages are supplied from the PV units. The results imply that the chloralkali process necessitates about 7.22 MW power to produce hydrogen at 25°C and 1 bar with an energy efficiency of 84%. H2 and CO2 gases are compressed to 60 bars with a total energy requirement of 951 kW. In the heat integration part, different scenarios are developed to determine the minimum heating and cooling requirements for maximum heat recovery. The results of such heat integration were achieved to conserve the energy in the formic acid process with total hot and cold utilities of 599 kW and 1884 kW, respectively.

Plantwide control and process safety of formic acid process having a reactive dividing-wall column and three material recycles

A holistic approach for process design, control and safety analysis through a model-based improved HAZOP that utilizes dynamic simulations, is presented and illustrated for the formic acid (FA) process. First, this study develops a plantwide control (PWC) system for the FA process having a reactive dividing-wall column (R-DWC) and multiple material recycles besides the snowball effect, presence of which poses difficulty in PWC. A systematic and hierarchical integrated framework of simulation and heuristics is used for PWC design. Performance of the developed control structure is assessed using several criteria having PWC perspectives. Results indicate that the developed PWC system rejects typical disturbances while maintaining FA purity. Finally, process safety is studied using a new model-based improved HAZOP, where quantitative as well as qualitative analysis can be performed unlike only qualitative analysis in conventional HAZOP. Novelty of this work is the study of PWC and safety of an intensified FA process.

Controlled phase synthesis of VmOn in differing oxidation states using a simplified formic acid process, quantified with a new generalized index designed for use with public domain material process information

This work reports a simplified low-cost environmentally benign synthetic process for the production of pure or nearly pure phase vanadium oxides in three different oxidation states, and quantifies the sustainability of the process with a green index.

Comprehensive analysis of two catalytic processes to produce formic acid from carbon dioxide

Carbon utilization (CU) based formic acid (FA) process is a promising option to reduce carbon dioxide (CO2) causing global warming but energy intensive resulting in a negative income effect on energy consumption. In the literature, catalytic conversion of CO2 to FA at low concentrations is focused and limited to recovery of FA with a high purity. This study presents two commercial-scale processes for catalytic production of formic acid (FA) from CO2, and conducts economic, energy and environmental analysis of them. Process B that uses an Au/TiO2 catalyst has a higher conversion by 3 mol% to 84 mol% than Process A that uses a Ru-Ph catalyst. Moreover, after catalytic conversion of CO2, Process B uses an additional amine shift reaction to recover FA with low energy consumption. Simulation of process design including CO2 conversion and separation of FA shows that Process B has a higher energy efficiency by 24.3% to 69.0% compared to Process A. However, Process A has a much lower reaction time (TR) than Process B, so the minimum selling price of FA (US$ 1,029/tFA) for Process A is more cost-competitive than Process B (US$ 1,037/tFA) with the current petroleum-based approach. In contrast, environmental analyses show that Process B has a higher potential by 0.3 tCO2/tFA to reduce CO2 emissions. If feasible positive assumptions (reduced TR; received carbon credits) can be met, Process B will also be techno-economically viable.

An advanced, efficient and highly durable of reduced graphene oxide/platinum nanoparticles nanocomposite electrocatalyst fabricated via one-step method of the hydrothermal-assisted formic acid process for the electrocatalytic oxidation reaction of methanol

The high-quality of reduced graphene oxide (rGO) supported platinum nanoparticles (PtNPs) was synthesized by a simple, efficient, rapid, clean, surfactant-free, and single-step of hydrothermal-assisted formic acid process. The as-synthesized rGO/PtNPs catalyst was extensively characterized in which demonstrated that the PtNPs have successfully anchored on the surface of rGO with the small average particle size of 4 nm. The evaluation of electrocatalytic activity and durability performance of the as-synthesized rGO/PtNPs nanocomposite catalyst towards methanol oxidation reaction (MOR) as well as the determination of electrochemical surface area (ECSA) were carried out by cyclic voltammogram and chronoamperometry. Besides, the as-prepared rGO/PtNPs nanocomposite catalyst has further proved the remarkably higher electrocatalytic property which exhibited superior maximum forward peak current density (64.04 mA/cm2) toward MOR in acidic media compared with Vulcan XC72/PtNPs (47.54 mA/cm2) and rGO/PdNPs (6.21 mA/cm2) catalysts owing to homogenous distribution and synergic effects of PtNPs with rGO as well as improved electron transfer by rGO. Moreover, the rGO/PtNPs nanocomposite catalyst still achieve the high current density even after 2900 s of continuous catalyst at 0.6 V. This study provides new insights into the production of superior electrocatalytic activity and durability of anode catalyst through a facile, low cost and clean synthesis approach for the enhancement of direct methanol fuel cell performance.

CO2 hydrogenation to formic acid over heterogenized ruthenium catalysts using a fixed bed reactor with separation units

An integrated continuous CO2 hydrogenation to formic acid process with trickle-bed reactor is developed using a heterogeneous Ru molecular catalyst.

Decolorization of methyl orange by MnO2/organic acid system: The role of Mn(III)

Decolorization of methyl orange (MO) by MnO2 was investigated with and without small molecules of organic acids such as formic acid. It was found that the decolorization could be significantly improved by MnO2 with the assistance of organic acids. The effect of various conditions was investigated on MO decolorization by using different crystal types of MnO2 and changing the types of organic acids. One of the optimum treatment conditions was δ-MnO2/formic acid system, which led to the removal efficiency of 90.6% at 30 min. The pseudo-second-order kinetic rate constant of δ-MnO2/formic acid was 0.1626. A reasonable decolorization mechanism involving Mn(III) species was proposed and the mechanism was validated by simple detection of ionic species such as, Mn(II) and Mn(III) during the reaction. The δ-MnO2/formic acid process designed here may lead to a new advanced oxidation technology based on the in-situ generation of active Mn(III) species and their ability for oxidation.

Design, Optimization, and Retrofit of the Formic Acid Process II: Reactive Distillation and Reactive Dividing-Wall Column Retrofits

Formic acid (FA) is an important chemical with many applications in the industry. Nevertheless, its manufacturing process has not received much attention in the open literature. In Part I of this series (da Cunha et al., Ind. Eng. Chem. Res. 2018, 57, 9554–9570), FA process was simulated and optimized for the production of 98 wt % FA. Total annual cost (TAC) of the optimal base case process was 0.686 USD/kg. This process was then retrofitted via integration of two distillation columns into a dividing-wall column (DWC), but such retrofit was not profitable. Here, in Part II, FA process retrofit via reactive distillation (RD) and reactive dividing-wall column (RDWC) are investigated in detail. Results show that RD retrofit is not attractive as it increases TAC of the process. However, retrofit via RDWC is profitable, resulting in a thermal energy savings of 20.4% and a TAC savings of 0.020–0.042 USD/kg (by 3%–6%).

Design, Optimization, and Retrofit of the Formic Acid Process I: Base Case Design and Dividing-Wall Column Retrofit

Formic acid (FA) is an important chemical with many applications in the industry. Despite this, the FA process has not received much attention in the open literature. In this work, FA process design and optimization are performed for the production of 98 wt % FA. Total annual cost (TAC) of the optimal base case process is 0.686 USD/kg. In addition, a recently developed methodology for process retrofit is applied, and retrofitting two distillation columns to a dividing-wall column (DWC) is investigated in detail. Results show that DWC retrofit is not attractive as it increases TAC of the process. The reasons for the increase in TAC are discussed. However, the FA process with DWC is attractive for a new plant, with lower capital and operating costs compared to the optimized base case process with conventional distillation columns.

Measuring and Predicting the Extraction Behavior of Biogenic Formic Acid in Biphasic Aqueous/Organic Reaction Mixtures.

The distribution coefficients and selectivities required for extraction purposes were predicted with a thermodynamic equation of state for the ternary system formic acid/water/extraction solvent. These predictions were validated with experimental data from the literature and experimental data from the oxidation of biomass to formic acid process measured in this work. Extraction solvents discussed in this work are 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-decanol, ethyl n-butyl ether, diisopropyl ether, di-n-butyl ether, benzyl formate, and heptyl formate. The considered temperature ranged from 273 to 363 K under atmospheric pressure. Perturbed-chain statistical associating fluid theory (PC-SAFT) was used for prediction purposes applying an approach as simple as possible and as complex as necessary to achieve trustworthy data for selecting the best extraction solvent. Using PC-SAFT allowed identifying 1-hexanol as the most promising solvent out of the 11 extraction agents. The predicted data were in good agreement with the experimental distribution coefficients and the selectivities, which are very sensitive to experimental uncertainties.

A “Fourier Transformed Infrared” Compound Study of Lignin Recovered from a Formic Acid Process

Lignocellulosic biomass is emerging as a renewable source of feedstock for biorefinery and chemical industry. Lignin, one of the three components of lignocellulosic biomass (together with cellulose and hemicellulose) represents about 22% of the total mass of the Earth's biosphere. Formic acid was used to dissolve lignin at various reaction temperatures. Infrared spectroscopy was used to study the influence of temperature on the functional groups of treated lignin. Thermal treatment of lignin with formic acid causes a decrease of OH functional group of lignin and an increase of phenolic hydroxyl groups especially at elevated temperature. Results revealed that formic acid treatment resulted in oxidative cleavage of bonds in the lignin macromolecule, leading to formation of oligomers of lignin.

Integration of Ambient Formic Acid Process and Alkaline Hydrogen Peroxide Post-Treatment of Furfural Residue To Enhance Enzymatic Hydrolysis

A novel integrated process with ambient formic acid combining alkaline hydrogen peroxide was developed to achieve efficient delignification of furfural residue. Furfural residue was treated with 88% formic acid at room temperature for 0.5 h followed by post-treatment with 1% alkaline hydrogen peroxide at 80 °C for 1.5 h. Results showed that 87.9% of the original lignin was removed and the solid residue obtained contained 84.6% cellulose. The glucose yield of the solid residue increased to 83.7% after 96 h enzymatic hydrolysis under a low enzymatic loading of 7 FPU/g cellulose. The analysis of the physicochemical property of the solid residue and lignin fractions indicated that there was an unapparent effect on formylation of cellulose during the ambient formic acid treatment, and the lignin rich in phenolic and carboxylic OH was easily removed. The insoluble-formsovl lignin in solid residue was effectively removed by alkaline hydrogen peroxide treatment.

Rapid Optimization of Typha Grass Organosolv Pretreatments Using Parallel Microwave Reactors for Ethanol Production

A comparative study of organosolv process was performed at laboratory scale using traditional stainless steel batch reactor with parallel microwave (MW) reactors. Ethanol (with sulfuric or soda catalyst), formic acid, and performic acid organosolv processes were first optimized for the pretreatment of Typha capensis using MW reactors. The best conditions based on mass balance and Klason lignin content were reassessed using a traditional pressure steel reactor. The enzymatic hydrolysability of soda process revealed better results (reducing sugar yields = 77–87%) as compared to the sulfuric acid process (reducing sugar yields = 57–66%). Substantially higher delignification and better enzyme hydrolysability were observed for the formic acid process with hydrogen peroxide catalyst. This process produced a pulp with very low residual lignin ( 85%). It can be concluded from this study that parallel microwave technology could be used for rapid optimization of bio...

Determination of the kinetics and mechanism of methyl formate synthesis in the presence of a homogeneous catalyst

The kinetics and mechanism of methyl formate synthesis, the key intermediate of the formic acid process was determined. Methyl formate was prepared from carbon monoxide and methanol in the presence of potassium methoxide as a homogeneous catalyst. Experimental work was carried out in a laboratory-scale semi-batch autoclave to obtain the intrinsic reaction kinetics. The experimental results were described with a plausible reaction mechanism comprising the reaction of potassium methoxide with carbon monoxide, followed by the proton transfer from methanol to the reaction intermediate to restore the catalyst. It was observed that simple first order kinetics fits the experimental data of the catalyst decomposition. A model for the gas–liquid mass transfer, coupled to the synthesis reaction was developed and the reaction of potassium methoxide was assumed to be the rate-determining step. The equilibrium, mass transfer and rate parameters included in the completely new kinetic model were determined with non-linear regression analysis. A comparison of the modelling results with the experimental data illustrated a good agreement between the model and the actual data. The kinetic and mass transfer models can be used for the scale-up of the methyl formate synthesis.

Isolation and characterization of wheat straw lignin with a formic acid process

There is a commercial need to increase the amount of industrial produced lignin. An 86.24 wt.% formic acid solution with 0.2 M H 2SO 4 as the catalyst was used to isolate the lignin of dewaxed wheat straw at different residence times and reaction temperatures. Lignin was extracted and purified separately from hydrolysates and residual solids after treatment. The lignin obtained has been characterized by FTIR (Fourier transform infrared), GPC (Gel permeation chromatography), and 1H NMR (Nuclear magnetic resonance). Results from these analyses indicated that oxidative cleavage of bonds in the lignin macromolecule has occurred during the formic acid treatment, leading to formation of oligomers of lignin with lower molecular weight. Moreover, it was found that guaiacyl unit is the main structure, the content of syringyl unit is higher than that of the hydroxybenzyl unit and β-O-4 together with β-5 ether bonds is also identified in the molecular structure of lignin of wheat straw obtained from the formic acid process.

Physical and electrochemical characterizations of nanostructured Pd/C and PdNi/C catalysts for methanol oxidation

Pd and PdNi nanoparticles supported on Vulcan XC-72 carbon were prepared by a chemical reduction with formic acid process. The catalysts were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), cyclic voltammetry, and chronoamperometry. The results showed that the Pd and PdNi nanoparticles, which were uniformly dispersed on carbon, were 2–10 nm in diameters. The PdNi/C catalyst has higher electrocatalytic activity for methanol oxidation in alkaline media than a comparative Pd/C catalyst and shows great potential as less expensive electrocatalyst for methanol electrooxidation in alkaline media in direct methanol fuel cells.

Alternative pulping process for producing dissolving pulp from jute

Dissolving pulps are the raw materials of cellulose derivatives and of many other cellulosic products. Jute is a very good source of cellulose and worthy of consideration for the production of dissolving pulp. In this investigation jute fiber, jute cuttings, and jute caddis were used as raw materials to prepare dissolving pulp by a formic acid process. A very high bleached pulp yield (49 to 59%) was obtained in this process. The alpha-cellulose content was 93 to 98%, with a high pulp viscosity. Also a good brightness (81 to 87%) was achieved in totally chlorine free bleaching. Jute fiber showed the best and jute caddis showed lowest performance in producing dissolving pulp via the formic acid process. R18-R10 values were much lower than for conventional dissolving pulp.